Oil leak - rear crank seal/backplate.
Discussion
Had an interesting couple of weeks with mine. Finally got the Raceproved slave fitted, but whilst doing that I noticed oil leaking from the rear backplate on the block/sump. Ordered in a new rear crank seal and fitted that this weekend.
Drove the car home last night and had to stop off halfway as I developed what I believe is a short in the steering wheel meaning the horn came on, constantly.
Checked under the car and noticed fluid dripping down (was half expecting it to be clutch fluid, again). Rolled the car back and it's oil, again! So it looks like the backplate/rear crank seal is leaking again.
Has anyone had any problems in this area before? I figured the backplate could be warped, but then the bolts should pull it back straight, and it certainly didn't look warped or damaged.
Cleaned both the backplate up nice and used plenty of sealant when putting it all back together. Reluctant to pull the gearbox and clutch off (will be 5th time in 2 months) again, but think it's inevitable.
Feeling like I'm getting there though, the car was driving quite nicely on the way home.
Drove the car home last night and had to stop off halfway as I developed what I believe is a short in the steering wheel meaning the horn came on, constantly.
Checked under the car and noticed fluid dripping down (was half expecting it to be clutch fluid, again). Rolled the car back and it's oil, again! So it looks like the backplate/rear crank seal is leaking again.
Has anyone had any problems in this area before? I figured the backplate could be warped, but then the bolts should pull it back straight, and it certainly didn't look warped or damaged.
Cleaned both the backplate up nice and used plenty of sealant when putting it all back together. Reluctant to pull the gearbox and clutch off (will be 5th time in 2 months) again, but think it's inevitable.
Feeling like I'm getting there though, the car was driving quite nicely on the way home.
Not yet, hoping to do it this weekend.
I got the new seal from RG (well, Clevor Trev) but I don't know if it was the uprated one or not. I didn't use a proper press to fit it, but I don't think it's too hard to fit it without a press. There is a lip to the backplate that the seal sits against. I used silicon sealant all around the lip so it should have been sealed properly.
I've got the backplate from my old engine just in case the one that's currently on there has a hairline crack or something.
I got the new seal from RG (well, Clevor Trev) but I don't know if it was the uprated one or not. I didn't use a proper press to fit it, but I don't think it's too hard to fit it without a press. There is a lip to the backplate that the seal sits against. I used silicon sealant all around the lip so it should have been sealed properly.
I've got the backplate from my old engine just in case the one that's currently on there has a hairline crack or something.
fatjon said:
It's very easy to crack the backplate/seal housing when refitting it, tiniest bit of s
t under it or uneven torquing of those bolts will do it.
Yes I can relate to this. I had to replace the cast oil transfer pipe due to a hairline crack. Thanks for the warning. t under it or uneven torquing of those bolts will do it. Hopefully the cause of your leak will be evident when you strip it down!
No fun at all doing a job twice. Good luck!
OP, did you have any joy with this? Was it a warped backplate?
We are currently having the same problem with mine, having put her all back together. My friend/mechanic is reluctant to strip the gearbox etc off again, and I am becoming rather bored of making the tea. Everything sealed up properly etc, including flywheel bolts.
We are currently having the same problem with mine, having put her all back together. My friend/mechanic is reluctant to strip the gearbox etc off again, and I am becoming rather bored of making the tea. Everything sealed up properly etc, including flywheel bolts.
Yes and no.
Changed the backplate for a spare one I had. The one I took out had a very slight warp to the lip the seal sits against and a hairline crack. However I don't think that was the problem as the seal should already be doing its job by that point.
The big problem for us was that several of the bolts had stripped the threads out of the block/sump. I think we had to re-thread/re-coil four in the end.Put it all back on with new sealant, etc. Didn't use a new seal however as that was the third one I had used in less months and it still looked perfect having only completed < 50 miles!
There is still a very slight drip, but only very slight. I've not had chance to see how much oil it uses/loses yet as the car is currently off the road again!
Changed the backplate for a spare one I had. The one I took out had a very slight warp to the lip the seal sits against and a hairline crack. However I don't think that was the problem as the seal should already be doing its job by that point.
The big problem for us was that several of the bolts had stripped the threads out of the block/sump. I think we had to re-thread/re-coil four in the end.Put it all back on with new sealant, etc. Didn't use a new seal however as that was the third one I had used in less months and it still looked perfect having only completed < 50 miles!
There is still a very slight drip, but only very slight. I've not had chance to see how much oil it uses/loses yet as the car is currently off the road again!
I'm assuming this is the seal that you use? http://www.racetechdirect.co.uk/tvr-car-part-e1276...
These seals should be fitted without any form of sealant. If the ring is a good tight fit in the housing then it will not be leaking past that outer side.
If there is leakage between the crank and the inner face then either there is a wear ring on the crank preventing sealing or the lip has not seated evenly.
I have seen Edd China use sealant on Wheeler Dealers when fitting this type of gasket and was amazed he had done so.
These seals should be fitted without any form of sealant. If the ring is a good tight fit in the housing then it will not be leaking past that outer side.
If there is leakage between the crank and the inner face then either there is a wear ring on the crank preventing sealing or the lip has not seated evenly.
I have seen Edd China use sealant on Wheeler Dealers when fitting this type of gasket and was amazed he had done so.
I think the issue here is poor quality back plate and fixing issues. I can relate to the cast oil transfer pipe. The replacement pipe flanges were bowed like a banana! Even though the o ring did the sealing, I used some honda bond sealant on the flange faces to compensate for tolerances and future cracking issues.
Looks like the rear crank seal is not an easy replacement seal, more an investigation! Stripped fixings add to the issue as the alloy seems quite soft too.
Looks like the rear crank seal is not an easy replacement seal, more an investigation! Stripped fixings add to the issue as the alloy seems quite soft too.
Supateg said:
I think the issue here is poor quality back plate and fixing issues. I can relate to the cast oil transfer pipe. The replacement pipe flanges were bowed like a banana! Even though the o ring did the sealing, I used some honda bond sealant on the flange faces to compensate for tolerances and future cracking issues.
Looks like the rear crank seal is not an easy replacement seal, more an investigation! Stripped fixings add to the issue as the alloy seems quite soft too.
I found the best silicone sealant to be Fiat's own. Wonder why? Looks like the rear crank seal is not an easy replacement seal, more an investigation! Stripped fixings add to the issue as the alloy seems quite soft too.
robsco said:
An update on this one. If anyone suspects a rear crank seal leak and changes it, check your oil pressure switch at the same time, it sits at the bottom of the V. It's probably worth changing it anyway while the gearbox is out, 20 quid including postage from Racing Green.
Was this the culprit for you after doing the rear seal? I did casually look to see if it was leaking on mine recently. I had the coil packs off early last year while sorting the big fuse and all was fine.
However thanks to your reminder, I will check thoroughly!
Got a minor drip from the slave so the box will be off before the summer season.
Thanks
However thanks to your reminder, I will check thoroughly!
Got a minor drip from the slave so the box will be off before the summer season.
Thanks
robsco said:
It's probably worth changing it anyway while the gearbox is out, 20 quid including postage from Racing Green.
Or about a fiver on eBay for an InterMotor part.http://www.ebay.co.uk/itm/221104615351
Interstingly Andy @ APM or Joolz (sorry forgotten who) reckons the 0.7 bar switch pressure is too low, and 1.0 bar would be more appropriate.
Edited by ukkid35 on Wednesday 5th February 21:26
Thanks for the link.
Pressure change makes sense. I'd prefer 2 bar !
Like most owners I keep a close eye on the oil pressure gauge! I Would like to think it could spot trouble before the switch!
On another subject I recall this switch is a common problem.
Would heat or vibrations lead to its early failure ?
Does it leak from the plastic joint with the metal?
Pressure change makes sense. I'd prefer 2 bar !
Like most owners I keep a close eye on the oil pressure gauge! I Would like to think it could spot trouble before the switch!
On another subject I recall this switch is a common problem.
Would heat or vibrations lead to its early failure ?
Does it leak from the plastic joint with the metal?
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