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PollyMobiles Rebuild

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pollyp

pollyp

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been having a long tiring exhaustive week at work and recovering from a cough hence no updates.

what happened last week at Andys.
arrived at 1pm, had abit of a chat, then a neighbour popped in for some car bits and summore chatting.
went to andys cosy toolshed to see afew tools, parts and shiny coilovers :cool:
talked more suspension.
talked bout h701s warmup & cooling issue, sounded like the lack of heater matrix shutoff valve prevents it from warming up and the radiator ain't performing when it does get hot.
he had a manual fan switch to turn it on, asked to turn off, watched the direction and angle of the fan spinning down. determined it was flowing the wrong way against incoming air hence didn't work well. needed to either reverse the motor, reverse the fan position or replace with a correct facing fan.

went for a drive with andy round the block through some twisty country roads to warm the car up, was also hungry so went for some grub, met alexia n kids on way back.
moved h701 onto the grass and parked car onto driveway.

DSC09368.JPG


starting to get dark so setup & level the balancing platform on andys drive, stood on each to test accuracy and they're all bout 0.5-1kg offset from each other. unloaded & raised car onto platform, set tyres to 3bars and began balancing.

started off with a 49% crossweight

Screenshot_2014-06-28-22-43-01.png


reduced the FL preload one turn to lower that corners load. increased crossweight 0.6% in the right direction

Screenshot_2014-06-28-23-19-44.png


lowered more and eh no difference

Screenshot_2014-06-28-23-29-07.png


rechecked FR tyre pressure cos that had a bad puncture leak, eek it dropped abit, really have to fix that.
pumped tyre back upto 3bars and jeez made a big change...
but then in our frazzled tired state I realised I forgot to disconnect the swaybars so all that balancing was pointless!:rolleyes:

Screenshot_2014-06-28-23-40-21.png


alright, bedtime.

next morning lets weld her up 1st as priority before balancing.
began cutting more and more chucks out the sills, I cut card templates, andy fabricates & tack metal on. welding onto old rusty metal was tricky. I had a go at MIG and was abit tricky to see or get a nice pool, was like blobby soldering. need more practice.

DSC09369.JPG


was halfway through the left sill then alexia reminded that it was almost 9pm on sunday (sky was still bright) so we had to hurry with the grinding. rather than fully welding & grinding smooth, we decided to just cut the pieces and just tack em all in for now and finish the welding next time.

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welded inner & outer pieces

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tacked the back faces on

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that'll do.

now lets resume balancing.

unhooked the swaybars this time, checked pressures and started off like this

Screenshot_2014-06-29-22-32-39.png


pumped up FR over 3bars to test its effect

Screenshot_2014-06-29-22-58-59.png


returned back to 3bars

Screenshot_2014-06-29-23-29-23.png


further reduced FL. but noticed the inaccurate scales, varying tyre pressures and sticky damper seals contributes to a huge amount of errors, so tbh trying to get to the nearest 0.1% is useless

Screenshot_2014-06-29-23-36-51.png


it was midnight and I'm tired and have a 3hr drive back home for work next morning.
andy says there's an auto event on july 20th for £10, yep going.

DSC09375.JPG


hopefully going back to andys this weekend for a final welding and balance should get her ready
 
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pollyp

pollyp

Club Member
Nice update Paul :)

New tips and shrouds on the welder so it'll be so much smoother this time around too :)

fab, we'll need to wirebrush back to metal cos road water has began the surface rust. I'll check with endoscope if the insides has rusted too. I need to buy more dremel cutting disks
 
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pollyp

pollyp

Club Member
Nice indeed Paul :)

Very interesting to note how much of an influence tyre pressures have.

yes, the random final resting point of the damper seal from the tiny binding
and the tiny variation in bars had a massive influence in corner load.
I think just 0.1bar changed the corner load by least 3kg
 

Low Rider

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yes, the random final resting point of the damper seal from the tiny binding
and the tiny variation in bars had a massive influence in corner load.
I think just 0.1bar changed the corner load by least 3kg

Yeah, as someone who is trying to absorb suspension info, it's very interesting. To me, it certainly highlights the potential for improvements on a car that's well setup. I just need to get my front polly bushes in...
 

h701micra

Deactivated Account
This reminds me Paul... H701 is taxed. We'll go play in a balanced car see if you can feel a difference :)

Amazing the differences a small change can make :)
0.5psi increments is how we normally adjust pressure.
You'll have to come do some corner weighting with sometime Dave :)
 
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pollyp

pollyp

Club Member
This reminds me Paul... H701 is taxed. We'll go play in a balanced car see if you can feel a difference :)

Amazing the differences a small change can make :)
0.5psi increments is how we normally adjust pressure.
You'll have to come do some corner weighting with sometime Dave :)

shweet, it may drizzle later on so pop the tent up.

perhaps one feature of a msc day out for those with coilover could include a corner balance before trackday at cadwell?
 

h701micra

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shweet, it may drizzle later on so pop the tent up.

perhaps one feature of a msc day out for those with coilover could include a corner balance before trackday at cadwell?
The port-o-garage is always up :D

I wouldn't mind but I fear some may be so far out it could be a few hours each :p

We'll have to see about freeing everything off to get rear adjustment too this time :)
 
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pollyp

pollyp

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The rear caliper guide pins seized so dropping the axle to adjust the spring perch will be tricky. unless we grind n replace the bolts but don't wanna risk it
 

h701micra

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The rear caliper guide pins seized so dropping the axle to adjust the spring perch will be tricky. unless we grind n replace the bolts but don't wanna risk it
We can look at our options when you're here :)
There's always a simple solution hidden somewhere
 
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pollyp

pollyp

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arrive saturday lunchtime. we talked for ages :D
and time running out, its 4pm already, better get a move on.

since h701 was taxed, we were gonna go refuel then drive around, but andy said she occasionally has trouble restarting from warm and worried we might not be able to restart her at the station if we turn her off, and the alternative of refuelling whilst still idling is abit dodgy.

so we got a petrol can, I drive us down to station for 5L, went back to fill h701, strapped self into the harness and commence riding shotgun :cool:
certainly a different raw shaking vibrating charactor compared to my luxery saloon :D
the deep vibrating seat rumble with exhaust gives a scary sense of huge energy in reserve.
I like how the harness locks you down with the car during cornering.
car certainly gets alot of attention :)
few minutes around the block and there goes 5L

parked my car in

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wirebrushed the area much as possible, tried welding some of the left panel but some parts were too thin flimsy as cheese blowing holes after grinding

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so just cut the section out and plug weld another panel behind, alot of grinding later till its flat

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sprayed black inside, began to tack the backing plate on and then we ran out of wire :rolleyes:

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the top welds holding and is a snug fit so will hold for now.
the main purpose of this weeks welding is just to seal the gaping rusty hole against road spray. it wasnt aimed to be a proper super neat rebuild for MOT, cos thats not due till Oct.
as it stands, it'll withstand all the MOT prodding no probs and ain't a structural thing, tis just external bodywork, and not bothered with neatness cos it'll be black.

structurally the panels are tacked on securely, andy fills the gaps with PU sealant to keep water out, further bond the panels together and give a slightly smoother finish

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paint black

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to hide it and does the job ready for an event next week at east kirby airfield

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we tried to look at the seized rear caliper bolts but no hand tools were working and no welding wire to fuse a nut onto the head so without wasting anymore time, bolt calipers and wheels back on and got starting on more interesting stuff.

andy began shortening these rosejoint swaybar droplinks to fit mine.

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just needs some m10 nuts & bolts to fit but first I'll need to refresh the swaybar bushes, fix the seized caliper bolts and re-corner balance the car in the coming days ready for next sunday
 

h701micra

Deactivated Account
Nice update again :)

Definitely need to look at those lock nuts the threads do still look short :p

Those sills, along with the wire running out and the co2 bottle falling over we weren't having much luck. We shall rebuild them again properly soon :)

Dont forget the restarting from warm it completely proved me wrong to make me look silly. We can safely open the taps next week ;)
 
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pollyp

pollyp

Club Member
yep I'll checkout B&Q n ebay tonight for the half nuts.

oh yeah forgot bout h701's bad ground. I explained how a rusty bad ground caused weak random starting issues when I first relocated the battery and thought your symptoms sounded similar.

looking at how your original -ve battery terminal was simply bolted to a black painted cabin sill with the seatbelt bolt, the paint will be badly affecting the conduction randomly.
you'd need to grind/wirebrush all the connection surfaces down to bare metal/metal from battery -ve to the starter motor casing to ensure the best electrical ground.

so suggest first grind smooth the battery -ve terminal and inner cabin sill to metal (preferably replace the original round -ve clamp with a DIY crimped copper terminal like mine) and see if it starts better, then followed by the start motor to chassis grounding cable.
 

h701micra

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I'm gonna make a plate up to give the rear mounted battery a dedicated earth point.
The seat belt hole was one of those "temporary" things that got forgotten

Currently loctite'ing bolts, brake checks, etc ready for the weekend
 
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pollyp

pollyp

Club Member
got a pack of m10 nuts bolts from BQ

DSC09396.JPG


drilled a hole through the collar to try tap more threads. its a very solid metal to tap cos the tool kept binding/stuttering so I tapped far as I dare without snapping the tool

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making some slim nuts rather than buy some. first mark the cut with a dremel on a drill

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hacksaw off and smooth on a grind wheel

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done

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slim nuts now on both left/right threads to get the most available adjustment

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trim the bolt length to the original

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lubed & ready to fit

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regrease the swaybar bushes with CV grease

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all fitted

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greased bush

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to fit the swaybar, the RH link had to be extended this much till it was slack. I just have to turn the middle collar 1/2 turn from zero slack and could feel it begin to resist as the swaybar begins to twist, so it's real handy for ensuring the bar ain't pulling to one side. the upper bolt required two nut spacers to keep the droplink upright.
the droplink can freely twirl about it's rosejoint under zero preload till the body touches the bolt edge so I suspect this might cause some noise at one point, the next test drive will answer that.
abit worried the link might be adjusted too far at it's last few threads, readjust soon.

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the LH link is fully retracted.

DSC09417.JPG
 

h701micra

Deactivated Account
We just need to figure how to replace the squishy front rubber swaybar links with solid adjustable ones andy
Already looking into it but enuo isn't far off :) we can have a quick look on saturday and see if anything becomes apparent when its in front of me

I've got those spacer for you if needs be, they'll prevent any knocking from the joint, looks fairly close to the bolt head already
 
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pollyp

pollyp

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driving to work and around country tday and no knocking so the rose joints fine.

front swaybar mounted like this

k750-88-jpg.31386


I got idea for the rose joint front linkage, gonna draw it later on. how many rosejoints you got left andy? prob just need two and fabricate the thing on saturday
 
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pollyp

pollyp

Club Member
time to fix the seized rear caliper bolts.
in the limited space, grinded the bolt head clean

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welded a nut onto the head

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and there's just enough weld to undo the bolt

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to get the bolt out past the handbrake bracket, cut the bolt apart

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the LH caliper bolt was stuck alot more. tried to weld nuts to it several times but couldn't weld properly with the limited access and the weld just snaps.
had a slight break and try again welding a bolt to it for abit longer and eventually loosened off

DSC09422.JPG


all guide pins regreased

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pollyp

pollyp

Club Member
measured bout 35mm between the front swaybar and the lower arm to fit the rosejoint, just enough

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there's a big oil stain all around the RH driveshaft area once again, perhaps this is one of the causes of the rapid oil loss?

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can't locate the exact source but signs seem to suggest either the turbo drain sump coupling or this corner edge of the sump that's always difficult to seal effectively

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regreased the swaybar mounts

DSC09432.JPG
 
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pollyp

pollyp

Club Member
The il return union looks to be weeping a bit, but not the real cause which looks to be the sump seal.

yeah agree, the oil seems to be leaking out that front corner edge, blown backwards towards the driveshaft and spun all over.

The front edge lip of that sump has a small crack in it from being pryed apart and bent back in place over the years. suppose I'll have to remove it and weld it up one day
 
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pollyp

pollyp

Club Member
bent some U shaped brackets for the front swaybar rosejoint only to find I've wasted afew hrs work cos the whole assembly is 45-50mm whereas the current linkage only has 30-35mm space so this won't fit :rolleyes:

DSC09433.JPG


front brakes checked with plenty of meat left.
feel I need to rebuild the rear calipers again cos they seem slightly sticky but cba.
think the boost solenoid is broke cos it no longer actuates, was useless anyway cos made no difference tbh.
only last thing to do is corner balance either tonight or tomorrow.
 
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Low Rider

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I'm all in for novel upgrades but I think it would be better to keep it simple and just upgrade to a set of polly bushes.
 
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pollyp

pollyp

Club Member
axial joint could fit if the female threaded end was shortened but to adjust it's length requires fitting washers so it ain't easily adjustable.

poly bushes are nice but the main issue we're resolving is how new or old swaybars become slightly twisted relative to the position of each wheel when the car is level. This means the twisted bar would be applying slight amount of uneven preload while the chassis is level which affects the final corner balance.

I need to design a linkage with an adjustable length, preferably on-car adjustable like the rear rosejoint, so that after the coilovers are perfectly corner balanced on a level platform, I can reinstall the swaybars and adjust each linkage till there's zero tension across the bar therefore won't upset the original balance.
 
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pollyp

pollyp

Club Member
tonight began corner balancing.

1/4 tank of fuel, swaybars still on, all tyres maintained at 3bars, lets see where is current stands

DSC09434.JPG


initial readings are (corner load, rim to arch distance, rim to floor distance) :
Front Right
292.7kg
106mm
65mm

Rear Right
171.3kg
106mm
71mm

Rear Left
175kg
104mm
69mm

Front Left
294.9kg
100mm
66mm

50.1% crossweight

1.png


now lets remove the swaybars and see how that affects the crossweight

(corner load, rim to arch distance, rim to floor distance) :
Front Right
290.8kg
106mm
65mm

Rear Right
173.6kg
106mm
71mm

Rear Left
172.9kg
104mm
70mm

Front Left
297.1kg
100mm
66mm

reduced the crossweight to 49.6%

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we need to relieve load off the FL/RR corner, reduce the FL load and increase the FL height.
the RR is perched abit high at 106mm so lets reduce the RR spring collar to try reduce the FL/RR load and lower the RR height and lift the FL height.

long task of removing the rear spring collars, clean and adjust.
the RL collar was 38mm from the top and RR was 36mm from the top so lets lower the RR so they're both sitting at 38mm from top.
coil springs coating has now all crumbled away like peeling king prawns

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with the RR loosened:
(corner load, rim to arch distance, rim to floor distance) :
Front Right
291.1kg
106mm
66mm

Rear Right
173.1kg
106mm
70mm

Rear Left
170.5kg
102mm
70mm

Front Left
300.4kg
95mm
66mm

eh, crossweight further reduced to 49.4% and the FL has gone the opposite way

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alot of load is on that FL, can't reduce the FL preload to reduce load or else the height will drop below 95mm.
cba to remove and lower that RR collar again.
perhaps the dumbells are weighing and sagging that corner too much so lets remove that 7.5kg ballast in the FL engine bay:

(corner load, rim to arch distance, rim to floor distance) :
Front Right
288.7kg
106mm
66mm

Rear Right
174.8kg
106mm
71mm

Rear Left
169.9kg
102mm
70mm

Front Left
294.7kg
96mm
68mm

crossweight remains same but that reduced the FL load, transfered to the RR and raised the FL

4.png


lets further remove another 7.5kg ballast off the passenger footwell:
(corner load, rim to arch distance, rim to floor distance) :
Front Right
286.7kg
105mm
66mm

Rear Right
175.7kg
105mm
72mm

Rear Left
167.4kg
102mm
70mm

Front Left
290.3kg
97mm
67mm

that's taken some load off the front and moved it to the RR but crossweight still at 49.4%

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previously the car was bounced from the FL corner.
I tried bouncing from the FR corner instead and wtf gives a perfect 50% crossweight.
the sticky damper seals have a really big effect in consistancy, the +/-1kg scales inconsistant inaccuracy doesn't help either.
K done

6.png


reinstalled the swaybars.
during fitting I can feel the front swaybar ends have a 5-10mm difference even though the chassis and lower arms are level.
(corner load, rim to arch distance, rim to floor distance) :
Front Right
289.3kg
105mm
66mm

Rear Right
173.4kg
105mm
72mm

Rear Left
169.9kg
102mm
70mm

Front Left
287.2kg
97mm
67mm

the twisted front swaybar transfers more load from the FR to the FL wheel, reducing crossweight to 49.9%

7.png


noting the binding damper seals affecting the readings, I rejiggle from the FL to get this

8.png


and rejiggle from the FR to get this

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seems the front swaybar really needs adjustable links and the sticky dampers & maxed out scales means trying to achieve the last 0.5-1.0% static crossweight is pointless.
 

h701micra

Deactivated Account
we need to relieve load off the FL/RR corner, reduce the FL load and increase the FL height.
the RR is perched abit high at 106mm so lets reduce the RR spring collar to try reduce the FL/RR load and lower the RR height and lift the FL height.
Increasing heights increases load, where a crossweight is higher. Dropping it below that pivot I was drawing on cupboard door :p
If you increased the FR & RL slightly to move that pivot the decrease is RR would've had a very different effect

That was the whole pivot point crossover I was on about :) I feel a lengthy conversation coming on later today :p
 
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pollyp

pollyp

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andy I'll be over abit late tonight cos was rebuilding the rear calipers tday and tis taking abit longer, then gotta bleed whole system, laser align wheels then pack up stuff
 
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pollyp

pollyp

Club Member
removed the rear calipers

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removed the external bits

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RH piston has a minor corrosion pit

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handbrake mech removed

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cleaned the old grease off and apply cv grease

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this bloomin c-clip is always a pita to install cos you have to compress the return spring and c-clip down into a specific groove. pushing down with pliers ain't working

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so to push it all down evenly, grabbed an old caliper piston, cut the head off so it doesn't foul the central threaded shaft

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use a socket over the hollow piston to push it all the way down till the clip hopefully clicks, but it didn't and felt spongy o_O

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removed the shaft to check and FFS the damn o-ring didn't slot into the hole and the excess force had sheared it apart

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used the old spare last one

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can see that the rubber is slightly too big plus there's no chamfered edge on the hole to guide it in, so after afew annoying attempts with a pick, it slotted in

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now I could install the c-clip with the hollow piston tool

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the LH piston looked fine and the handbrake lever was working so will leave that alone and just reassemble both calipers

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brakes fitted, bled, all bolts checked, cba with alignment, it's straight enough.
have dinner, shower, packup n go.

estimate I'm there bout 10-11pm andy
 
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pollyp

pollyp

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arrived at andys on saturday night, watched some videos, decided to sleep in the car cos it's much cooler than the living room.

was a damp sunday morning, we first bled the brakes cos the pedal was quite squishy driving down last night, twas bubbles in the rear lines. set off at 8am and the brakes feel much better now.
follow andy to the venue at East Kirkby Airfield in Coningsby while alexia, in the picaso with his tools n stuff, drop the kids off before popping over.

2014 Mablethorpe District Motor Club Auto Triathlon

arrived at 9am, signed in, walked track and briefed. the space between cones look extremely close thinking how heck do I fit the car through? and when the guy demonstrated with an estate, k it fits.
first session is a points driven autocross, not timed but marked on lowest penalties, 10pt hit cones, 10pt wrong way, 3 runs.
first runs began in numbered order straight after brief, but alexia hasn't arrived yet for storing all our heavy tools n stuff, so we'd have to go around fully loaded.
I didn't have a passenger so had to share Rob with andy, bet he was well chuffed having 6 autocross rides in 2 micras :)

IMAG1041.jpg


as a first autocross, the route was quite technical to learn all the turning points, least they're numbered.
first run in a heavy micra on an unknown track an not used to rally notes so I'll just drive by memory and look out for numbered cones



1:40 with 1pt.
alot of turns were alot tighter than the map shows, so had to reverse several times n loose time.
2nd gear in the first section was too steep so will have to stick to 1st.
disc handbrake is useless.
picaso still hasn't arrived so I just unloaded my stuff onto the grass side nearby before the 2nd run.
brake fluid slightly overfilled so sucked out the excess with a plastic bottle/tube/ducktape.



same 1:40 with 2pts.
turning too early for tight hairpins once again losing time reversing.

here's andys 2nd run from track side



alexia arrived. the final run, try to take it abit steady, thought I clipped one cone in mid-section, take a wider sweep at the tight turns so I don't lose time reversing.



1:35 with 1pt.

trackside view thanks to alexia.
sun has been shining and the day's getting extremely hot.
concerned bout turning the car off with all that heat soak. everything is just super hot with the blazing sun, zero wind and mechanically stressful low speed autocross driving.

 
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pollyp

pollyp

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next session was an untimed blindfolded autocross with Rob.
I noticed alot of passengers in 3dr were sticking out the window to get a better view but really couldn't see the cones from the drivers corner, so I told Rob get in the back seat of my 5dr windows down, so he'd be able to simply pop the other side to clearly judge the drivers side too. worked a treat with zero pts :cool:

final session was an interesting driveby & throw hoop challenge.
there are dart boards and cones at key spots around a autocross. we drive round first lap while the passenger shoots a suction gun at the targets, pts for misses, then the 2nd lap they throw fan belts onto cones, pts for missing.
andys run with half of Robs torso out the window blasting round the course was flamboyant but nerve racking hoping he didn't fall out :eek:
here's my run



had no idea where the 2nd section cones go so got abit lost but meh.

while rob was with andys run, I thought why not find a another passenger so I don't have to wait for rob? so asked around and found a lovely helping lady for the last 2 runs :)



all the runs have been exactly the same time.

at the ceremony, andy won the shoot & hoop challenge but surprisingly they awarded me for travelling the longest distance from north east to make this event :) it's an awsome privelage to accept n treasure this award, thanks to everyone from the MDMC :D

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andys last run seem to have popped the top rad hose off and empty the coolant. engine was very hot, although his gauge still says cool, suspect the sensors out of spec?
he fitted the hose on, filled with water but she's having trouble starting and kept stalling at idle, holding the throttle up kept it running but inconvenient for junctions on the way home.
we bled the fuel hose, checked plugs, doused the ign coil in water, same idle stall.

I suspect the idle control was stuck closed in the heat cos I recall on a K11 when the old waxstat cam sticks open and ppl fully close the idle bleed screw to compensate and the IACV closes during warm idle, it tends to idle too low n stall.

as a get home measure, I ziptie a small rock under the throttle pedal bumpstop to tension the cable and open the throttle abit. it idles high but least it prevents stalling on the way home.
we begin the journey home, few miles down he pulls over cos the idle control has return back ad idle revs high so we removed the ziptie, loosen the cable back and she's back to norm.
have a feeling the extreme heat may have caused the idle valve to seize shut briefly on track and the drive home allowed everything to cool off n shrink returning to norm.

well thats been a fun day
 
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