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PollyMobiles Rebuild

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pollyp

pollyp

Club Member
Too thick oil may strain the oil pump when cold but that's it really... unless you're putting tar in it :)
Edit: Strain if you rag it when cold

hmm ok so this wet piston ain't affected much by oil grade then.
I always drive normal n gentle and without heater till she's fully heated before I load the engine
 
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pollyp

pollyp

Club Member
car's packed but at silly hours why am I still modifying lol

been meaning to make a plastic shield for the pod filter against the water spray during downpours especially since its forcasted to rain at JAE, but supermarkets don't sell any clear acetone OHP sheet anymore and local staples have shut down.

scrabbling round the house found a large food tin can that just fits over my old pod filter

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painted

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but my current halfords pod filter (left ) is slightly smaller than the old ebay filter (right)
so decided to just tape the shield to the old filter and use for rainy weather while the newer halfords filter will be for clear weather

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fitted in place. had to remove the washer bottle filler cos it was in the way

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so had to cover it with some bottle cap that kinda fitted, tis just to stop stuff falling in

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pack some clothes, have breakfast then we're off tomorrow :cool:
 
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pollyp

pollyp

Club Member
I'm in no way undermining your work you've done a tremendous job but if it was me building such an engine with the doubled up use of a daily driver I personally believe forged pistons are unsuitable for the reason mentioned above

yeah i realised after googling into forged pistons when I was first rebuilding it, that they may not be suitable for normal use due to their massive clearances n noise etc

I sense trouble coming ahead if this engine can't pass emissions and have to decide whether to
  • throw all that work, money & windage tray R&D away n find/fit a bog normal engine in to pass MOT,
  • find a stock engine, swap my windage tray on that and fit it,
  • or this car purely becomes a track car (no guarantee if this oil issue will be fixed) and buy another bog normal STOCK k11 for daily use
I have moms car to use all year so my car can be off road for whatever period but I swear this car is spending most of it's life in the garage off-road than actually being used, like moms car :rolleyes:
 

h701micra

Deactivated Account
yeah i realised after googling into forged pistons when I was first rebuilding it, that they may not be suitable for normal use due to their massive clearances n noise etc

I sense trouble coming ahead if this engine can't pass emissions and have to decide whether to
  • throw all that work, money & windage tray R&D away n find/fit a bog normal engine in to pass MOT,
  • find a stock engine, swap my windage tray on that and fit it,
  • or this car purely becomes a track car (no guarantee if this oil issue will be fixed) and buy another bog normal STOCK k11 for daily use
I have moms car to use all year so my car can be off road for whatever period but I swear this car is spending most of it's life in the garage off-road than actually being used, like moms car :rolleyes:
Shouldn't throw all that work away.
In reply to your earlier thicker oil question I think thinner oil may help after all.
Thicker oil will obviously expand in heat and thin itself down slightly... so in theory that would increase both crankcase pressure and capacity? Maybe use a tad less? To allow for expansion or use thinner to reduce capacity once warm?
Just ideas to try
Though a dedicated track car could be entertaining

;)
 

SuperUno

Buy & Sell Member
Not suggesting you break the law, but if the MOT Emissions is your only issue here, then can you not find a 'friendly' MOT man. I have one for the rally car but he is in Essex, which i still go back to as it saves all the hassle........

Once just before a rally when i had emissions issues and needed the MOT to do the rally, £50 cash changed things quite a lot, and was cheaper than other options.....
 
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pollyp

pollyp

Club Member
JAE 2013

2013-09-12
Car drove there perfectly, pistons still half damp and has consumed 1/2 dipstick after 200m.
Arrived on a dry thursday at 3pm and saw Ralph, Iris & Joe who got there earlier, ralph scaring ppl with his quadcopter :)
Celina n Karl arrived followed by Harlen and Charlotte then Mik, James, Carrie, Louise, Chris, Gemma, both Andys, and many others.
tent popped up with help from celina. then saw toms car with chloe inside being pushed on stand, it overheated during the long entrance queue.
first day was alot of setting up, ooh ahhing at cars and catching up and meet new friends :)

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no time for giving ppl lifts cos it was getting dark early so do it tomorrow.
the generator was broken so no power or lights, only had headlights from james celica and karls civic.
got talking with both andys all night till silly 5am :p everyone was asleep but we got carried away still talking in the silent pitch black morning till before sunrise talking suspension setup n oil n turbos n pistons etc :p

was a productive night/morning cos we concluded that all the oil symptoms my forged piston has shown all the way could've been heat related.
the forged pistons have a high expansion rate and are meant to operate at high racing temps.
by running them just on the roads with a relatively cool stock 82C thermo, the pistons may not be getting hot enough to grow relative to the blocks own expansion and the poor clearances may be allowing tiny bit of oil to seep past the inner or outer side of the rings.
the next test would be to make it run hotter (partially block radiator or fitting a hotter thermo and/or taking her to the track) and see if the pistons dry up from the tighter clearances.

2013-09-13
Friday morning gave Charlotte a ride in the car as Celina insisted, did I spot a grin as I briefly boosted it on the slip road :)
Chris's injector plug wire had snapped so then gave him a lift, goes abit quiet when I boot it :p prob just soaking in the sensations.
got few tools in maplin to repair his loom.

next gave Celina a lift who just couldn't wait like an excited kid lol along with Tom who knocked his head on my cam rig, oops soz tom :p
back at base we inspected toms motor. rad was dry, plugged plugs out and woah cyl1 was full of coolant from failed fire ring. other pistons are just damp. tis going nowhere but says he has breakdown recovery so prob best option. later on andy mentioned thoughts of swapping toms engine tomorrow, on wet grass with min tools and no crane, sounded mental and barely achievable but very difficult n dangerous within a day.

2013-09-14
next morning talked with glen that the original plan would be very risky.
getting a used 1.3 out of a scrap micra with little tools will take afew hours, working under the low car with no support would be insane, no containers for the old fluid, ripping the old engine out again few hrs, fitting the spare engine another few hours. doing it within a day with potential rain is crazy. also doesn't guarantee it'll work so could be a waste of money, time, stress and safety.

He suggested fixing the HG instead which is much easier n safer n cheaper, mentioned to tom and we did that.
I didn't have all the tools required so gathered resources. took the cover off to verify the required tool sizes n what needs buying from halfords.

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tom had difficulty finding a micra HG from any local factors on a saturday, even chris had no success but maybe could try temp sealant as last resort.

gave louise, chloe n tom a lift to halfords to buy a headbolt tool, sealant and coolant followed by few supplies at tesco where we bumped into glen who mentioned stan had franks tel who might have a spare gasket.

phoned frank and he has one yay :) but he's busy with charity and I'd have to drive there bout tea time.

guys hired another generator and got power now.

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remove the head and omg what a mess.
the HG around cyl1 was totally perished so no metal epoxy was gonna fix that, and the coolant jacket had massive clumps of what appeared to be solidified radweld! this could be whats blocked the jacket, rad and more reason to advise ppl never to use it.

at this point there's quite a crowd building up from around the show and was told this was historically a first at jae, huh really? I'm thinking surely there'd be least some enthusiasts who'd least had to service/fix their cars at shows from a breakdown at some point so that was a o_O

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5pm time to drive to franks in birmingham which was a long 1hr drive. took stani along and farewelled everyone.
1hr through blinding sun n traffic we got to frank.
what a legend he is :D fab enthusiastic fella, told us bout the victor reinz HG that the dealers repackage as £70 when they're actually sub £15-30!

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then he dangled his car keys at me like a donkey carrot pointing at his white micra, huh what? o_O oh what me drive your turbo car? :eek:>:)>:D>:cool:
mind was thinking am I allowed/covered, what if? and before mentally answering thought ah fookit :p
sit in, seat was fixed so had to adapted position like when I once drove the oversized-kart ariel atom. what a privilege to experience such extreme experimental beast from the skunkworks of frankville:D

cold start instantly, oil pressure take few millisec to build like on mine, blip throttle to get feel and gosh its so sensitive n weighty n responsive like it has alot of power reserve off a bigger motorbike engine. clutch was light n vague bite but just had to modulate and adjust technique for now. brakes far from throttle and spongier so can't heel toe. no PAS so needs more effort than usual :p

squeezed out the driveway onto the roads for a short blast. with the static seat, sensitive throttle and vague clutch its such a different feeling driving interface, almost scary from the unknown as I first approach the roundbout in heavy traffic thinking "please don't crash don't crash!".
enter the open straight in 3rd, open the tap and phwoa what is this thing, it's insane! lol short throttle gives sensation of huge potential, then the boost gradually builds n pushes like my 160ftlb. face is like :D
change to 4th and there's hardly any woosh from the bov which is what I'd want on mine. 4kg flywheel drops instant for a snap shift and quickly reached 40mph limit.
approach next roundbout, brake, blip shift down and wtf as fast as I blip the pedal, the ultralight crank instantly revs up like a semi-auto supercar, faster than I can blink :eek: I'm super impressed by that responsiveness and made more :D

returned back at franks, stalled once but ecstatic :) what a day to remember, it's like between my turbos torquey drivability with the super response of the atom. makes my car feel like a ship liner afterwards lol.
super thanks to frank for the opportunity.

drove back 1hr to jae by 7pm and twas dark. flood lights on toms bay all setup like a tv show and a big crowd greeting from such a loving community, really special support ;)
advised by lovely carrie to eat first before resuming.

Mik being the theatrical type guy a-ha's the crowd and announces my entry like a star lol
we then concluded how this was abit like mighty mods where mik was moog and I was asian marty :D
twas a surprising and unusual feeling to be center of a crowd attention which was nice n distracting but I had an engine to fix in short time so while enjoying the support, remain focused n calm n do what I normally do at home.

was about to fit the head but had to stop n cut out lights cos of the fireworks, which was awesome in the perfect clear sky :cool: everyone applaude n honk horn, hazards, rev cold engines to death, me n louise walk down the stands for her first time to observe such special occasion, then andy removed his manifold to make even more noise but got told off by park rozzys, woopsy.

lights back on, back to work. head on n torqued, cams, chain and cover on, everything hooked, primed oil n coolant, start and she fires up on all cyls yay. big blowby from the cyl2 exhaust gasket I missed, bled rad but she kept bubbling n dropping level and smoke out the back. think the heads warped n unable to fully hold the gasket, bumma.
we're tired so lets pack up n bed n get it recovered home, poor chloe looked really exhausted facedown on the steering wheel with duvet :/

2013-09-15
up early to pack up cos frank said big rain coming by 10am. all day packing n cleaning up the stand n guys returning home. tom arranged rac van but soon found barclay only supplied a 10mile recovery, he's 120m away, couldn't upgrade his account so ended up paying a full £280:eek:
the cars able to barely run but with big ploom of smoke and having to stop every 5-10miles to fully fill the coolant plus the last few single lane A-roads don't have any lay bys, it'd be inconvenient, slow and hazardous. getting it trailered was the only wise choice but hurts the wallet. cash can be regained but his and chloes safety cannot and is not worth risk of going macho for. was a sad part but least they're safe.

all packed n ready, had a quick go in andys racecar k10 with fun hydraulic handbrake, then he had a whizz round only to be told again by guards:rolleyes: what is it with em picky bouncers, cant have a bit of fun far away from anyone in a clear field. first was me last yr and now andy. meh

farewells to carrie, louise, james and away we go back home in 4 slow hrs to a soft bed and hot shower n back to hectic work the next day
 
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pollyp

pollyp

Club Member
to look for a hotter thermostat I measured the spare housing.
the outer lip has to be within 55mm, housing bore is 50mm and the internal ribbing sticking out at 10 & 2oclock meant the core has be be within 39mm (or the ribs can be grinded away)

I googled 90-92-95c stats and found a few that appear to fit, mostly from ebay and alot for volvos.

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95c BMW wahler stat
http://www.ebay.co.uk/itm/230400303401?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

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90c jeep cherokee/wrangler
http://www.ebay.co.uk/itm/151118954841?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

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90c Stant for various jap cars
http://www.ebay.co.uk/itm/161011749424?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

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92c volvo s90
http://www.ebay.co.uk/itm/300864377...ff11=ICEP3.0.0&ff12=67&ff13=80&ff14=54&ff19=0

92c volvo s40
http://www.ebay.co.uk/itm/300864377...ff11=ICEP3.0.0&ff12=67&ff13=80&ff14=54&ff19=0


so many to choose from.
checked halfords cos i remember I once brought a k11 thermostat from them so must have a stash to physically compare but surprisingly they don't sell em anymore :( so have to rely on buying online
 
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pollyp

pollyp

Club Member

just wanna up the thermostat only with minimal work. those housings cost more than the stat.

think the jeep cherokee stat seems to be the cheapest and best fitting one to get
 

frank

Club Member
the stat is sealed inside i believe paul, and the cream coloured ones are 88deg apparently, which could be fitted in series with the stock stat :)
 
When I did the conversion into the mini I needed to angle the thermostat outlet, I discovered that the mini thermostat housing was a direct replacement. I'm pretty sure that I fitted a 82c mini thermostat as well :-/ might be worth looking up the mini thermostat sizes?

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Glen

Club Member
Have you thought about using a bigger turbo and running more boost which will surely cause the engine to run hotter plus you will have alot more power. Just your current setup is good its just not stressing the engine.
 

Enuo

Glorified Electrician
Have you thought about using a bigger turbo and running more boost which will surely cause the engine to run hotter plus you will have alot more power. Just your current setup is good its just not stressing the engine.
That's a fair point, it's also win win
 
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pollyp

pollyp

Club Member
Have you thought about using a bigger turbo and running more boost which will surely cause the engine to run hotter plus you will have alot more power. Just your current setup is good its just not stressing the engine.

changing to a bigger turbo will provide potential to reach higher "peak" boost and less exhaust back pressure but at the cost of a higher boost threshold and lag resulting in poor throttle response.

increasing the "peak" boost will help increase power and torque and ultimately peak temperatures yes, but only during prolonged WOT such as on track (which I haven't tested for yet) and also pushes components further towards failure.

during street driving the car is hardly ever pushed long enough to produce much heat, spends most of its time off-boost hence bigger turbo/peak boost has minimal effect to the core issue.

the core issue is not peak temps (racing it around the track will resolve that), but instead it's the overall operating temps during normal low stress driving conditions such as cruising and idling in town which isn't getting the pistons hot enough to their optimum temps for sufficient clearances and could be leading to this oil control issue.
 
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pollyp

pollyp

Club Member
Get this bolted on with supporting mods and start to make serious power and the pistons and rings will bed in http://pages.ebay.com/link/?nav=item.view&id=130988998626

my goal isn't about just making serious silly short lived puwwer (anyone can do that by fitting a high flowing turbo/SC/NOS etc ... for afew secs before boom) it's about a manageable, reliable and drivable horse power:cool:

that turbo is overkill, heavy, laggy for a 1.3L, expensive and as frank said that label is placed at the silliest point where the hose joint actually requires a smooth uniform surface to seal. basically seems like false showy "look at me" bling with short lived or short delivered reliability.
 
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pollyp

pollyp

Club Member
really peed off tday cos I just got a letter bout a parking fine of £100! (£60 within 14d) for staying too long at a Welcome Break services on 15th:mad:

hmm 15th, that was when I was driving home from JAE, was really tired so for safety I pulled over at services for a quick nap before resuming and now they throw a fine for not noticing the 2hr limit banner in my tired state?:rolleyes:

OK next time you can forget bout the thieving services, I'll park in some quiet roadside or P spot instead.
 

h701micra

Deactivated Account
Why do they advertise so much about "tiredness can kill" etc then penalise someone for heeding that warning.
I pulled over for fresh air and a drink but it was an abandoned petrol station... sort of place you wouldn't wanna stay too long :p
 
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pollyp

pollyp

Club Member
Get it round that track Paul ;)

when I have the time and money off my crazy work schedule. I'm working like 12hrs a day for no pay as a start up company till we get contracts and have no life. wish I could go work with ralph in Sweden on design stuff that I luv and qualified for but I'm stuck at home here destroying my brain over longer hrs than an average worker in the hopes this new company takes off big:oops: tis life suppose and taking a safe risk of seeing where this goes.

btw before I forget, thanks for the Rolls Royce overalls ;) machine had to wash it several times cos twas soo mucky but looks smart. nice upgrade from me old unbranded suit to a Rolls overall :cool:
I may not have a Rolls car but have my own Rolls uniform :)
 
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pollyp

pollyp

Club Member
Why do they advertise so much about "tiredness can kill" etc then penalise someone for heeding that warning.
I pulled over for fresh air and a drink but it was an abandoned petrol station... sort of place you wouldn't wanna stay too long :p

aye tis a ridiculous taxing country, there's just nowhere safe to park any vehicle other than in ur own garage.

did you see any ghosts or zombies at the abandoned station lol :p
 
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pollyp

pollyp

Club Member
went to partco and asked for a 92C thermo for a 97 volvo s90.
£13 and it fitted the spare housing.

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so here's a motorad 92C thermo kit

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has a bleed valve and this odd looking end piece, dunno what its for

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fits the housing perfectly

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that end flange is close to the housing. once the thermo opens backwards it could touch the sides.

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motorads site shows it's actually a sprung loaded valve so when the thermostat opens, it shuts the coolant return port, forcing the coolant to flow through the rad rather than back to the pump



so it can be removed

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inside it says 91C/195F

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lets first test it beforehand.
I place it in a bowl and pour boiled water into it with thermometer starting at 95C but the valve hardly budged, huh? is this broken? tried again and still no response since the moment I poured boiling water in :/
so rang partco asking if I can change it for another thermo such as a Cherokee but have to wait till monday cos other suppliers shut.

bah, ok lets try again but this time gradually heat it up and keep it at boiling point on a stove.



you can see the temps go up to max 100C boiling, water now vapourises as steam rather than getting hotter.
turn flame off to stop the bubbling and see the thermostat and it's clearly fully open now.

OK so it does work but now learned the wax in the thermostat has a slow response time so has to be gradually brought upto and beyond its marked temp rather than flash heated before it begins to open.

as the temps drop, it begins to close at 95C and fully shut at 92C therefore it has a operating window of 92-95C.

now I cut the end copper off to remove that flange

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trim the rest of the copper off. looks like this additional valve closing feature is just pressed over the thermostat body.

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and clears the housing much better

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normal genuine nissan 82C thermo with the 92C thermo

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fitted

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once the sealants dried n filled up, lets see how it performs and if the cylinders improve :cool:
 
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h701micra

Deactivated Account
when I have the time and money off my crazy work schedule. I'm working like 12hrs a day for no pay as a start up company till we get contracts and have no life. wish I could go work with ralph in Sweden on design stuff that I luv and qualified for but I'm stuck at home here destroying my brain over longer hrs than an average worker in the hopes this new company takes off big:oops: tis life suppose and taking a safe risk of seeing where this goes.

btw before I forget, thanks for the Rolls Royce overalls ;) machine had to wash it several times cos twas soo mucky but looks smart. nice upgrade from me old unbranded suit to a Rolls overall :cool:
I may not have a Rolls car but have my own Rolls uniform :)
Been there done that 4 years ago now :) my advice would be stick at it. My first year I took no money for pay. Minimum profit to tie over business expenses. Its all worth it in the end
Ah the overalls. You need to thank @enuo for those :)
aye tis a ridiculous taxing country, there's just nowhere safe to park any vehicle other than in ur own garage.

did you see any ghosts or zombies at the abandoned station lol :p
I know right

Maybe I was too tired to notice :p
 
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pollyp

pollyp

Club Member
Been there done that 4 years ago now :) my advice would be stick at it. My first year I took no money for pay. Minimum profit to tie over business expenses. Its all worth it in the end
Ah the overalls. You need to thank @enuo for those :)

I know right

Maybe I was too tired to notice :p

yep it's tough work but I'll stick to it cos any other option is a radical commitment and costly.
plan is to see if the hard work pays off, if we can get enough clients and profit to sustain and build it up. when it succeeds and things get stable secure and easier and I have a life back, then I could reopen and reconsider my options.

ah yes course its enuos cos he worked on spitfires n aircraft engines.
Thanks Enuo/Andy :D

aye I was too tired to be bothered to notice but lesson learnt, never park n sleep at services or any built up area with cctv and especially never park in london
 
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pollyp

pollyp

Club Member
well started her up, drove out town to warm up.
cold temps climbed up past normal 82c,
then at 92c i wondered is it gonna open or overheat?

got nervously close to 95c, now the wax body is hot enough and opens the thermostat.
the hot coolant flows through the stone cold rad and temps drop down fast.
by the time the thermostat realised its below its 92c mark and starts to shut the valve, the cold rad has already heat soaked and cooled the coolant down to 85c.
now it rises back up from 85c with the valve shut.

once it reaches 93c the thermostat opens,
coolant now flows through a pre-warmed rad, so the temp drop from heat-soak is not as rapid but still cools quite effectively.
temps drop down to 87c before the valve was shut.

and once the cars up to operating condition and driving normally, the average operating range of the thermostat is now 88-93c

previously the standard 82c thermostat gave an operating range of 77-82c during normal driving and 84-88c during trackdays, bout 6c hotter.
so theoretically the hotter thermostat will make it run bout 95-99c on track.

after gentle cruise through town, checked pistons, still half wet.

went for a blast through the country 3-5k brief WOT, check pistons, still half wet no change :oops:
 
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pollyp

pollyp

Club Member
it,ll be interesting to see what your temp gauge hangs at now paul, i,m very tempted myself now :)

temp gauge still at 1/2 way.
this 10c increase hardly registers on the gauge giving its operating range from min/max

wonder why do cars in uk run at 82c?
 

h701micra

Deactivated Account
temp gauge still at 1/2 way.
this 10c increase hardly registers on the gauge giving its operating range from min/max

wonder why do cars in uk run at 82c?
It has alot to do with ambient temperature. Colder you fo the hotter the engine setting top cope and vice versa.
I was really hoping the hotter thermostat temp would help :(
 
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pollyp

pollyp

Club Member
It has alot to do with ambient temperature. Colder you fo the hotter the engine setting top cope and vice versa.
I was really hoping the hotter thermostat temp would help :(

before the rebuild with the looser original ring expanders, the pistons were either 10% dry or mostly wet.
straight after the rebuild with tighter expanders, they were all 10% dry
after a long cruise to JAE n back they were 50% dry
and now after fitting the hotter thermostat its still bout 50% dry. I'll have to record another borescope video soon

so I think it's getting better.
plugs all white from burnt oil
 
Whats your thoughts on really giving it a boot full paul? not a 3-5k brief 'blast'. more like a 6k prolonged hooning around? remember that coolant temp is not the same a piston temp..

edit: Ill happily come do it for you if you need, just saying....
 
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pollyp

pollyp

Club Member
Whats your thoughts on really giving it a boot full paul? not a 3-5k brief 'blast'. more like a 6k prolonged hooning around? remember that coolant temp is not the same a piston temp..

edit: Ill happily come do it for you if you need, just saying....

lol I'm sure you'd be happy to :p

I've reved it upto the limiter before in short bursts during the break in stage and slip roads with no improvement on wetness.

maintaining/cruising at 6k whilst within the speed limit ain't producing much boost and ain't good for it and will sound like a yob :p

trying to maintain WOT at 6k for long periods without hitting the limiter is impractical without speeding alot

and I'm trying to resolve this issue within the normal driving conditions, which is where it spends most of its time as a daily. driving like a yobo n breaking laws may briefly improve the heat that the pistons need but public roads is not the place for it.

the best place for testing if its a heat issue as mentioned before is the racetrack, once i have time n money.
if that eliminates the wet piston, then its a heat issue and we just need to bring street driving temps further up.
if it doesn't, then we have a problem and can't run this engine on the road
 

h701micra

Deactivated Account
I think it may be simpler to call a compromise here Paul
You've got a race engine in daily use I dont think they're issues that will be readily solved within daily driving parameters
 

Enuo

Glorified Electrician
92 degree 'stat and thicker/hotter oil are the only things that will help with wet cyls on day to day driving if the temp is the issue.
 

Ed

Fusion Motorsport
MSC Founder
Official MSC Trader
Car drove there perfectly, pistons still half damp and has consumed 1/2 dipstick after 200m.

was a productive night/morning cos we concluded that all the oil symptoms my forged piston has shown all the way could've been heat related.
the forged pistons have a high expansion rate and are meant to operate at high racing temps.

by running them just on the roads with a relatively cool stock 82C thermo, the pistons may not be getting hot enough to grow relative to the blocks own expansion and the poor clearances may be allowing tiny bit of oil to seep past the inner or outer side of the rings.

the next test would be to make it run hotter (partially block radiator or fitting a hotter thermo and/or taking her to the track) and see if the pistons dry up from the tighter clearances.


It's your build I'm afraid. Something is wrong with the piston rings. Pains me to say, but 1 litre in 200 miles is appalling oil consumption on a new engine. Diamond honed bores should NOT smoke at new OR use oil. What are your ring gaps?
 
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pollyp

pollyp

Club Member
I think it may be simpler to call a compromise here Paul
You've got a race engine in daily use I dont think they're issues that will be readily solved within daily driving parameters

which means it's not likely to pass emissions = no mot = not driveable
so when mot has expired I'd have to either give up this engine and fit another stock 1.3 to pass emissions and use the car daily,
or make it solely a track car and buy another normal car for daily (but getting the trackcar to a track requires a trailer/frame which I don't have nor space for)
either way it's gonna be expensive.

when the mot expires do I have to sorn it or could it be done later on if the oil issues resolved?
 
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pollyp

pollyp

Club Member
92 degree 'stat and thicker/hotter oil are the only things that will help with wet cyls on day to day driving if the temp is the issue.

will have to try thicker 15w40, damn I just brought a new bottle of 10w40 too :oops: meh tis just £17
 

Enuo

Glorified Electrician
will have to try thicker 15w40, damn I just brought a new bottle of 10w40 too :oops: meh tis just £17
Take it back and swap it, they won't mind :)
That said I don't think 15 weight will make THAT much difference, maybe try 20w50 with that 92 degree 'stat, if you can store your current oil so you have somethibg you can swap back to if it doesn't like the 20w50
 
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pollyp

pollyp

Club Member
It's your build I'm afraid. Something is wrong with the piston rings. Pains me to say, but 1 litre in 200 miles is appalling oil consumption on a new engine. Diamond honed bores should NOT smoke at new OR use oil. What are your ring gaps?

new bores, new rings, new shells, stiffer oil expanders, hotter thermo, and the same problems still there. the only last cause would be the pistons themselves. there's nothing more I can do now short of paying thousands for an engine specialist to restart it all over again and ain't worth it tbh

I read the dipstick at jae on a grassy slope so twas prob abit off. I think Min to Max on the stick was bout 750ml? so 1/2 a stick is bout 0.35-0.4L per 200m. but yeah tis an unusually large consumption for a new build.

it doesn't smoke during cold-hot starts anymore now, yet to record a recent onboard exhaust video on WOT to see if it still smokes oil on full pull.

after bed-in, the gaps roughly 0.356mm top, 0.457mm second, 0.457mm oil
http://micra.org.uk/threads/pollymobiles-rebuild.35251/page-92#post-624126
 
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pollyp

pollyp

Club Member
Take it back and swap it, they won't mind :)
That said I don't think 15 weight will make THAT much difference, maybe try 20w50 with that 92 degree 'stat, if you can store your current oil so you have something you can swap back to if it doesn't like the 20w50

I've already opened n used abit of the 10w40. the dipstick oils already dark after jae so prob just change it to thicker stuff.

that doesn't seem right, that I'd have to use really thick 20w50 on a rebuilt engine?
thought a new engine should be able to run thinner stuff? although this big clearance forged engine might be an exception? just seems counter intuitive.
and I think we discussed that the 20w50 may have caused the stuttering appearance on the big ends?
 

Enuo

Glorified Electrician
I've already opened n used abit of the 10w40. the dipstick oils already dark after jae so prob just change it to thicker stuff.

that doesn't seem right, that I'd have to use really thick 20w50 on a rebuilt engine?
thought a new engine should be able to run thinner stuff? although this big clearance forged engine might be an exception? just seems counter intuitive.
and I think we discussed that the 20w50 may have caused the stuttering appearance on the big ends?
Yeah, but at 10 degrees hotter it will be thinner, 10 degrees hotter on the 10w40 oil might make it too thin. Also if it was run in on thick oil it'll probably run better on thicker oil now...
 
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pollyp

pollyp

Club Member
Yeah, but at 10 degrees hotter it will be thinner, 10 degrees hotter on the 10w40 oil might make it too thin. Also if it was run in on thick oil it'll probably run better on thicker oil now...

shall I work up the grade progressively? 15w40 semi - 20w50 semi
or fully synth
or you recommend sumthing? have no idea what the ideal oil is
 
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