andyfreelandy

Well-Known Member
Getting set to change the Cambelt on my lad's Borrego Yellow F1, took Cambelt covers off and my word, an oily mess everywhere, over belt, pulleys etc. Will post photos but the source of the oil is high up. Probably a cam seal or the cam cover gasket or both.
Two questions please.
1) Are there any other sources of oil leak behind the cover, at pully height or higher?
2) Cam seals press in but instructions with seals say not to press in fully, just 1mm below surface of cam housing. Anyone come across this instruction? All seals I have done fit in until they sit flat on the rear edge.

BTW, both rear engine cam seals are also leaking so hopefully that is the problem at the front.
 
It cam oil seals are the most common seal to fail, often due to incorrect fitting when the HG has been done.

It's correct to only press the oil seals in a short distance. I don't measure them, but 1mm below the face would be about right.
 
Thanks, strange to make the recess too deep, gives a risk that the seal can go in not square on.
Will be on to this before changing the belt!!!
 
Yes cam seal/s are your best bet. I've one that's leaking and it makes a real mess, the oil eventually creeps around both sides of the block. Do you re-use the cam cover seal or toss it away and fit a new one? I'm going to reuse mine but give it a clean and apply the Wurth sealant to both sides, it's what I use for the cam carrier.
 
Cam ends seals can be popped out and replaced without touching cam cover. If the cam cover isn't leaking I'd leave it alone!

I will be investigating the cam end seal bore depth and the seal depth to see if a aluminium washer can be fabricated to allow for the seal to be pushed square in to the bottom. Don't like the ldea of a seal halfway down that can move or tip sideways.
 
Will take accurate measurements but you can get 2mm thick ally sump plug washers that would clear the cam and sit neatly in the recess for the seal to sit on top. Any reason why this wouldn't be an improvement???
 
It cam oil seals are the most common seal to fail, often due to incorrect fitting when the HG has been done.
I suppose it's sensible, before doing them, to ask, what is correct way to fit them!?
Sealant or not, lubricated inside or not, etc..
 
I suppose it's sensible, before doing them, to ask, what is correct way to fit them!?
Sealant or not, lubricated inside or not, etc..
No sealant or lube is necessary, as the seals should come pre-treated with a fitting lube.
 
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No sealant or lube is necessary, as the seals should come pre-treated with a fitting lube.
I've used 'house brand' seals, MG Rover, Corteco, Allmakes... and I've not noticed that that pre treatment. I put a smear of clean engine oil on the seals 'lip' to help them slip into position. Would that have any negative effect or shorten their life span or reduce their sealing effectiveness?
 
Pulleys and belt off, having lined it all up and checked timing.
Back top belt cover has been rubbing on pulley and has melted!
Replacement on its way.
All seals removed, not an easy job as aware of alloy case and potential cam end damage. Used a hook tool but tricky.
Cleaned all oil off and washed all pulleys with solvent.
Ready to refit now and fit belt.
 
Cleaned all oil off and washed all pulleys with solvent

Check the pulleys in a couple of day for oil 'bleeding', as the sintered material absorbs oil, which then bleeds from the surface over time.
Sometimes repeated cleaning is required, if oil contamination is deep.
 
Thanks John, will repeat clean as I have a few days awaiting the replacement rear belt cover.
Looks like one mount broke, the old cover rubbed the pulley and melted!!
 
All double cleaned and new cam rear cover arrived.
Fitted up and another surprise! When I removed the 2 RH engine mount bolts they both came out with a lovely slither of aluminium in the threads leaving the threaded holes as smooth as a wossisname !!
Fortunately I had another engine block mount which I swapped out while it was off. It looks like the old dissimilar metals or someone forced them in badly cross thread.
Belt now on, all lined up and tensioner set up.
Will leave until morning, rotate a couple of times, check then covers on.
This has ended up being a fairly big job but hopefully I saved the engine from an unscheduled cam belt failure!
 
It looks like the old dissimilar metals or someone forced them in badly cross thread


The previous repairer has probably used the bolt threads as devices to pull the engine into the correct position, rather than lifting it so the bolts are able to thread in easily.
 
All done. Starts and no oil leaks!!
Here's to another 80k.
Not a difficult job to change the belt on a 1.8k. It was all the other stuff that I found. I bought a £5 tool to save the valve springs from fighting me as I fitted the new belt.

https://www.ebay.co.uk/itm/Rover-Gr...2349624.m46890.l49286&mkrid=710-127635-2958-0
I tried using one of those but couldn't get the belt tight enough between the exhaust pulley and the crank pulley resulting in the cams being half a tooth out. I should have turned the crank pulley back a little, fitted the belt and retightened it but instead faffed about with the cam pulleys.
If I ever have to do it again I'll try it this way.
 
With the tool in place and the crank on the dot it all fell into place without a fight.
Plastic tube in the crank end to hold the belt and fit the tensioner.
Maybe I was lucky!!
 
With the tool in place and the crank on the dot it all fell into place without a fight.
Plastic tube in the crank end to hold the belt and fit the tensioner.
Maybe I was lucky!!
Are you 100% certain you're not half a tooth out at the cam pulleys?
The belt needs to be so tight from the exhaust pulley to the crank pulley it is pretty much impossible to fit it without turning one of them back a bit. After turning the engine over a couple of times and setting the crank to it's mark you would find the cams are just a fraction out. Because the issue is one tooth out between the crank and the cams it shows up as half a tooth out between the cams with the crank on it's marks.
The car will still start and run but will not be optimal.
 

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