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PollyMobiles Rebuild

I heard those are smaller dia? nissan4u part # also shows 1.3L flys r only on 1.3 engines?
1-piece?
could u measure it?
 
the starter ring on mine is 273mm dia

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I've just read that copper washers may need annealing before reuse or after it was stored a long time, to soften it up n ensure a good seal? maybe I shoulda annealed the big oil gallery washer when I fitted it new to stop this leak?
gonna take the washer out, inspect and see if it can be reused or replaced. sump washer def needs replacing cos its been crushed paper thin over the yrs
 
I use that copper sealant on things like that
Did a bit of research in the process of making my copper sheet head gasket
Copper doesnt seal well as it doesn compress and conform and surfaces have to be completely true, what about a different material washer?
 
removing the oil plug, can see a slight hint of oil residue

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cleaned up the washer and here's the plug side, look at the contaminant at the bottom, might have affected the seal? it scraped off with my fingernail

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the engine side looks flat n clean

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heated it dull red with the blow torch

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carefully wirebrushed the carbon off, the contaminant left a slight dimple on the outer surface

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smeared some copper sealant on the washer

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tightened the plug hard as I can, lets hope it works

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to decide whether to replace the input bearing, a non-scientific way of checking the amount of bearing play was to slot each input shaft into the bellhousing, anchor the measure tape and read the amount of give from wiggling the end side to side.

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the current shaft with the worn 5th gear has 1.5mm of play while the prev old shaft (which I believe also whined) has 2mm of give.
I think the best option is to replace the bearing to be safe.
the NSK 6305 ball bearing is like £8 and getting a local shop to source n fit the bearing is prob a doddle.
buying a £10 gear puller and hammering the new bearing on myself just ain't worth the risk of damage.

measuring the other end of the shaft to see how much its worn, the current shaft with worn 5th is 28mm dia while the prev old shaft is 28.01mm dia so is newer.

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Check LSD

The red permenant threadlock did their job keeping the bolts on tight

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but now some of the threadlock was also sticking the top onto the LSD body so couldn't nudge it off, instead I'd have to try pull it off

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made this little puller and it pops off

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preload washer still in two pieces since last time it was opened

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LSD emptied, threads need cleaning

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lsd plates laid out

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the clutch plates measure: (feb 2012, mar 2013, aug 2013, oct 2014, nov 2014)
outer 1 - (1.90 , 1.89 , 1.89 , 1.94 , 1.92)
inner 1 - (1.75 , 1.73 , 1.73 , 1.74 , 1.76)
outer 2 - (1.10 , 1.54 , 1.53 , 1.55 , 1.55)
inner 2 - (1.54 , 1.53 , 1.53 , 1.52 , 1.53)
outer 3 - (0.95 , 0.94 , 0.93 , 0.94 , 0.94)
inner 3 - (1.53 , 1.53 , 1.53 , 1.54 , 1.53)
outer 4 - (1.55 , 1.34 , 1.33 , 1.32 , 1.33)
inner 4 - (1.55 , 1.53 , 1.53 , 1.54 , 1.53)
looks like since it was last rebuilt in March 2013, it's hardly worn at all

top face of the ramp driver looks smooth n normal

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numbered the ramps we'll be inspecting

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Ramp #1
quite a big defective chipping, developed between when the LSD was last rebuilt Aug 2013 and last time it was rechecked in Oct 2014 (after bedding in forged engine and afew trackdays)

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Ramp #2
small hairline crack begining to form

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Ramp #3
Opposite the chipped ramp #1, it's developed the same sized chip and is about to fall out

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Ramp #4
The only ramp that looks intact. interesting to note it's been stamped the 1.5way ramp angles 80/45deg braking/acceleration

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checking the pinion gear cross-pins thats forced against the ramps

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look at how the pinion shafts been hammered against the ramps n indented a flat edge. think this may affect a slight amount of play of the pinion in the ramps between braking & power.

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looking at the shattered beville washer. the upper side looks the same as last time.

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but since Oct after the recent trackday at cadwell park & blyton park, the underside of this washer has developed two more fracture lines

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the longer piece looks the same as last time

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underside

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I have a theory to the series of events that may have caused the damage.
- this LSD was last rebuilt back in march 2013

- march 2013 to jan 2014 the forged engine was being rebuilt & bedded in so the LSD wasn't under much stress or milage. opened LSD in Aug 2013 and preload washer was still intact.

- feb 2014 trackday at elvington. never opened the gearbox but preload may have reduced abit? dunno what's causing it but the beville washer may have started to crack here.

- may 2014 trackday at cadwell. almost no preload now. with a weakened cracked preload washer, the pinion gear has alot of slack within the ramps so when I tend to drop the clutch abruptly during upshifts due to the heavy flywheel, the sudden shock of the pinion slamming! into the ramps may have began to chip a corner off and further fracture the beville washer.

- after afew trackdays in july, august, opened the LSD in Oct to find the preload washer fractured in two and one ramp chipped

- nov 2014 trackday at blyton park, the chipped ramp allowed more uneven stress onto the opposite ramp making it chip and begin fracturing the other ramps

Was thinking could it be caused from aggressive upshifts on track due to the heavy flywheel? but this fracture had also happened previously with the light JUN flywheel/paddle clutch on track.
perhaps the preload washer really can't handle repeated abuse of 160ftlb?

I think our next step to try resolve this issue once for all is to replace the weak beville washer with more solid clutch plates instead,
plus replace the chipped 80/45 ramp planet driver,
indented pinion cross-pins,
maybe have the heavily pitted top cover & 1st clutch plate machined smooth/replaced cos the preload would be more sensitive to any tiny changes in thickness.
 
when john at Gripper once told me it could handle the 160ftlb my setup produced, I'm wondering if that meant 160 at the fly or at the wheels.
he said their diffs worked fine on other racing cars over 500bhp, but I think those have the full two-sided clutchpacks whereas mine only has the 1/2 sided clutchpack so the poor beville can withstand only half the max load.
the dyno printout that Ed at Fusion gives out I believe are readings from the wheels? so the actual torque going through the diff in a low gear could be much higher?
this is just guesswork at the mo.

SirChris was urs dyno'd on Ed's, what was ur torque readout? did ur planet driver have any defects like mine when it was apart?
 
Surely that's the other way round?
80 acc 45 dec?
My understanding of a 1.5 was that dec was 50% of acc

from wiki
A 1.5-way differential refers to one where the forward and reverse limiting torques are different but neither is zero as in the case of the 1-way LSD

some lsd quote ramp angles from vertical (along axle axis) whereas Gripper quotes their ramp angles from horizontal (along rotation direction).
so for grippers, lower ramp angle = more wedge/clamp force against plates.

from Grippers site it says at the bottom
Current ramp angles available are 30/65, 40/65, 45/45.
mine's obviously a custom ramp.

ramp.jpg
 
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Paul any chance you could nab some pictures of how the the 5th gear selector fits in with the other two selector rods. Not sure if mine is correct
 
sent email to gripper bout rebuilding the LSD but no reply yet.

was originally gonna get a garage to source & replace the input shaft bearing and the diff bearing (since posting the diff to gripper would prob damage the bearing shell) but figured I could do it myself.

was looking at the input bearing skf 6305 £8 and the diff bearing 30208 £25 but considering the condition and demands of my daily use with occasional trackdays, decided to get a complete rebuild kit instead including all bearings & all oil seals for £55 on ebay

http://www.ebay.co.uk/itm/171173762235?_trksid=p2060778.m2749.l2648&ssPageName=STRK:MEBIDX:IT
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will need a bearing puller too for £12
http://www.ebay.co.uk/itm/231394147101?_trksid=p2060778.m2749.l2649&ssPageName=STRK:MEBIDX:IT

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new bearings would be hammered back in carefully with a socket or spare pipe.

the rocker cover gasket was prob leaking so ordered a new one
http://www.ebay.co.uk/itm/191409595464?_trksid=p2060778.m2749.l2649&ssPageName=STRK:MEBIDX:IT

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oh bugga, only just realised that the 3pc gear puller won't be able to remove those tapered bearings off the diff or gear shafts since the fingers r too bulky. oh well, but I'll be able to do the essential input bearing.
 
3pc bearing puller arrived

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before I could pull the bearing off, needed to buy a flat snap ring plier at machine mart

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snap ring removed

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the larger puller just fits but it was very hard to tighten the screw by bare hand, need to secure the puller

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clamped the puller on a vice and now I can crank on the screw

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and the bearing slowly pulled out

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this obviously ruined the old bearing. awaiting the new bearing set to arrive.
john at gripper still hasn't replied to email, will need to use the good ol fasion phone
 
bearing kit arrived

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bearings for the diff, layshaft and input shaft

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nicely provided some sealant too

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all the oil seals and input shaft roller bearing

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layshaft oil feed

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diff seals

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input shaft seal

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input shaft end bearing

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input bearing, this is odd, it says nsk 6304C3 rather than SKF 6305 on mine

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diff bearing

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googled the 6304C3 bearing and it has a different dimensions to my 6305, then I searched nissan4u comparing the 1.0L gearbox to my 1.3L and I've been stupid and brought a bearing kit for a 1L gearbox which I thought had the same bearings but instead it uses completely different bearings to the 1.3L
FFS why didn't I realise this before:rolleyes:

now I gotta return it back and order another input bearing:confused: this is gonna be a long rebuild
 
Re Ed's print outs of power runs, i thought they were at the flywheel? Else i have 126bhp and 100ft/lb at the wheels!!!! Its fast but i suspect not that fast, feels more like those figures at the flywheel.
 
when john at Gripper once told me it could handle the 160ftlb my setup produced, I'm wondering if that meant 160 at the fly or at the wheels.
he said their diffs worked fine on other racing cars over 500bhp, but I think those have the full two-sided clutchpacks whereas mine only has the 1/2 sided clutchpack so the poor beville can withstand only half the max load.
the dyno printout that Ed at Fusion gives out I believe are readings from the wheels? so the actual torque going through the diff in a low gear could be much higher?
this is just guesswork at the mo.

SirChris was urs dyno'd on Ed's, what was ur torque readout? did ur planet driver have any defects like mine when it was apart?
mate we are pushing no where need the maximum of the diffs. i remember a birdy telling me like something around 400, as its the same design as something else and they saw that figure. mine was 150/150
 
my dyno printout was 162HP
http://micra.org.uk/threads/pollymobiles-rebuild.35251/page-26#post-456606

I read that trying to calculate the actual engine output on a rolling road is a rough estimate at best cos there's so many tiny little parasitic variables that will affect the accuracy of the result including:
tyre traction, sidewall rolling resistance, tyre pressure, tread depth, drivetrain inertia, drivetrain friction, oil seal friction, CV joint friction, all bearing friction, etc
for the actual engine output to compare against the manufacturers original spec, nothing can match hooking the engine alone to a dyno, but that's impractical for most ppl.

mate we are pushing no where need the maximum of the diffs. i remember a birdy telling me like something around 400, as its the same design as something else and they saw that figure. mine was 150/150

chris have you ever taken yours on track or was it only on public road? is that estimate 150bhp/150ftlb?
the birdy telling you 400 sumthing? was that for a gripper diff with an offset clutchpack & beville washer, over 162ftlb and combined daily/track circuit abuse?
I think as a daily on public road the diff is fine cos there's not much stress going through it for long (and the past evaluation during the engine bed-in supports that).
whereas, since I took it on track, the constant 162ftlb WOT loads and shock loads from upshifting with a heavy flywheel seem to push it upto and beyond the preload washers operating limit and the past 3yrs of constant fractures seems to suggest that.

john at gripper got back to me saying send it over and they'll rebuild it under lifetime warranty over 3days.
I asked if that washer will be removed to stop this happening again or whether it'll just be rebuilt back to the same insufficient setup and most likely fail again on track, which is very inconvenient. I can't justify having to do this EVERY year wasting both mine & Grippers time & money.
if it keeps breaking I'll prob have to look at either a VLSD or an expensive geared LSD for more reliability. anyone fitted a torsen/quaife/eaton diff with the standard speedo gear on a k11?
 
I personally don't bother with LSDs at these lower power levels. Its perfectly controllable with the right foot
If the diffs are assured up to 500hp I can't see 160 giving it many problems. I'd be pointing my finger at how its assembled. Something can't be right somewhere

Nissanubaru I've gone with the LSD equipped drive train because of the significant power to weight ratio
 
how much did that set you back?

whoa I just googled the AP suretrac diff, found this site looking inside the diff and geez it's a rubix cube of a diff :confused:
www.mycaterham.com/66828/117416.html

View attachment 38132
Works well on tarmac and gravel, better on gravel than i was expecting to be honest. At the moment the diff i think is offering more performance than I as the driver can fully extract from it especially on gravel.

Will PM you a price.
 
my dyno printout was 162HP
http://micra.org.uk/threads/pollymobiles-rebuild.35251/page-26#post-456606

I read that trying to calculate the actual engine output on a rolling road is a rough estimate at best cos there's so many tiny little parasitic variables that will affect the accuracy of the result including:
tyre traction, sidewall rolling resistance, tyre pressure, tread depth, drivetrain inertia, drivetrain friction, oil seal friction, CV joint friction, all bearing friction, etc
for the actual engine output to compare against the manufacturers original spec, nothing can match hooking the engine alone to a dyno, but that's impractical for most ppl.



chris have you ever taken yours on track or was it only on public road? is that estimate 150bhp/150ftlb?
the birdy telling you 400 sumthing? was that for a gripper diff with an offset clutchpack & beville washer, over 162ftlb and combined daily/track circuit abuse?
I think as a daily on public road the diff is fine cos there's not much stress going through it for long (and the past evaluation during the engine bed-in supports that).
whereas, since I took it on track, the constant 162ftlb WOT loads and shock loads from upshifting with a heavy flywheel seem to push it upto and beyond the preload washers operating limit and the past 3yrs of constant fractures seems to suggest that.

john at gripper got back to me saying send it over and they'll rebuild it under lifetime warranty over 3days.
I asked if that washer will be removed to stop this happening again or whether it'll just be rebuilt back to the same insufficient setup and most likely fail again on track, which is very inconvenient. I can't justify having to do this EVERY year wasting both mine & Grippers time & money.
if it keeps breaking I'll prob have to look at either a VLSD or an expensive geared LSD for more reliability. anyone fitted a torsen/quaife/eaton diff with the standard speedo gear on a k11?

lol i suppose ur setups alot meaner n u drive it harder. will get back to you in a year and with track abuse and see if the diff is still fine.
 
Works well on tarmac and gravel, better on gravel than i was expecting to be honest. At the moment the diff i think is offering more performance than I as the driver can fully extract from it especially on gravel.

Will PM you a price.
for that price as 2nd hand, certainly an affordable alternative option to consider if this one fails again and my income improves
 
new input bearing slipped on

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needed a tube with a 27mm+ inner bore, found this off an old push scooter

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slip it against the inner bearing race and hammer it down

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till I was able to fit the snap ring back on. spins much smoother

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now to reassemble the LSD. retapped all the bolts & threads clean from threadlock, reinstalled the plates dry cos I know they're only gonna clean n inspect everything anyway.

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bolted up hand tight n repackaged to be posted off.

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wth? the diff was posted on tuesday via special delivery guaranteed (apparantly arrive by next working day) and for the past 4days the tracking status been stuck at "out for delivery" and no word from gripper bout it :mad: rubbish service royal mail, wth did I pay for? better not be lost
 
Royal mail has had a propper melt down over the last few weeks.

My 24hrs special delivery signed for took 9 days.

yikes. suppose tis all this black friday/cyber monday/etc online xmas demand and also reduced workforce thats just overloading their infrastructure?
think I read if it took over 7days u can claim compensation from delayed service?
 
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