ZT190 KV6 Camshaft Oil Seal Swap - Tips?

[Randyjim]

Hi all,

My ZT190 has a leaking camshaft oil seal at the front of the engine, nearest the drivers side headlight. Unfortunately the camshaft has been damaged, and part of the end of the shaft where the timing notch is has broken away leaving sharp edges. This has caused the inside lip of the seal to become damaged (most likely during fitting)and a resultant leak.

Fortunately there are no sprockets involved to overcomplicate the job, but access is limited between the cylinder head and the PAS reservoir. Does any body have any tips, or tool suggestions, to help get this swapped as easily as possible please?

Thanks,
James.

[vitesse]

If you have an old cam bolt left over from the belt changes, use it together with a large socket to press the new oil seal evenly in place. Wet the oil seal with some fluid that will evaporate, fit the new seal in place by hand, and finally press into place.

Good luck

ps Use a self-taping screw to remove the old oil seal

[xsport]

Getting the old seal out should not be too much of a problem, but fitting a new one maybe. The best time to have done this was when the belts were changed , when access to both sides of the engine camshaft were there. now you will have very little room to play with , as you have now realised. A good idea suggested by another member (mr toad) on here was to use a joiners long clamp, which seemingly worked very well.It was used end to end on the camshaft and clamped together. The new caps can be difficult to start squarely and i found that replacing the old cap was much easier ,provided it was not damaged,especially on the lip seal.If the rear belt cover can be removed ,you could try this method with a long clamp. It would be possible without the opposite belt cover removed ,but risks damage to a brittle and not very robust set up. Some members have bought oil seals and done the job, but with limited success , with leeks recurring , and rust appearing on the shaft ends in some cases. (application of grease on that could suffice ) I have used a pry bar and wooden blocks to re insert a new one ,which turned out to be extremely tight , but that is very difficult to get square on access without damage to the cap ends,but achievable. You will need to lift the P.S pump out of the way now to generate enough room to do any work,and maybe hoses and cables. If you can obtain a decent pre used one to fit ,that will help alot. Theres no easy fix for this . ....

[xsport]

Originally Posted by vitesse

If you have an old cam bolt left over from the belt changes, use it together with a large socket to press the new oil seal evenly in place. Wet the oil seal with some fluid that will evaporate, fit the new seal in place by hand, and finally press into place.

Good luck

ps Use a self-taping screw to remove the old oil seal

Nice one vitesse !! Im glad someone has other means . Its always nice to hear someone has an alternative and i will have a go at this on my next belt change. Wish you had mentioned this years ago !! Thanks very much for your suggestion ... Sounds good . ..

[vitesse]

Originally Posted by xsport

Nice one vitesse !! Im glad someone has other means . Its always nice to hear someone has an alternative and i will have a go at this on my next belt change. Wish you had mentioned this years ago !! Thanks very much for your suggestion ... Sounds good . ..

Thanks for the feedback. Unfortunately I can’t claim ownership but learnt this trick from an ex-MG/Rover mechanic here in Gävle (Sweden). One of those, 60+ mechanics who makes everything look so easy and effortless, while we mere mortals curse and swear when things don’t do our way.

Keep well

[SD1too]

Originally Posted by Randyjim

Unfortunately the camshaft has been damaged, and part of the end of the shaft where the timing notch is has broken away leaving sharp edges. This has caused the inside lip of the seal to become damaged (most likely during fitting)and a resultant leak.

Hi James,

Can I clarify which part you are referring to as "the seal"? Is it the exhaust camshaft end cap which covers the end into which the valve timing service tool fits during belt replacement?

If so, surely any replacement will be also damaged by the fractured camshaft, leaving the problem to be tackled at source.

Simon

[Randyjim]

Originally Posted by SD1too

Can I clarify which part you are referring to as "the seal"? Is it the exhaust camshaft end cap which covers the end into which the valve timing service tool fits during belt replacement?Simon

Funnily enough the part I'm referring to as "the seal" is the seal. I believe orignially it would have been a cap, but seals have been fitted instead at least since the previous belt change in 2017 carried out by a specialist recommended through this forum. whether this is where the cam was broken I don't know, it wasn't mentioned at the time. Reading these forums suggests replacing the caps with seals is common practice these days due to lack of availability of quality caps, with aftermarket parts having a tendancy to fall out.

Originally Posted by SD1too

If so, surely any replacement will be also damaged by the fractured camshaft, leaving the problem to be tackled at source

Not true. If it was "the seal" that was fitted at that 2017 belt change would have leaked too and not lasted succesfully for 6 years. I fully expect that with a little extra care during fitting damage to the seal can be avoided. It's the technique to do this in a confined and awkward space that I'm hoping to unearth here.

Looks like I need to stock up on PAS fluid and be ready for a fight.

[SD1too]

Originally Posted by Randyjim

Funnily enough the part I'm referring to as "the seal" is the seal. I believe originally it would have been a cap, but seals have been fitted instead ...

Thanks Jim, I'm familiar with that procedure.

Originally Posted by Randyjim

Reading these forums suggests replacing the caps with seals is common practice these days due to lack of availability of quality caps, with aftermarket parts having a tendency to fall out.

The original end cap design doesn't fall out if it is properly fitted. However that is not easy. Without doubt the best method is that pioneered by Mr Toad and described by xsport above; the use of a long woodworker's cramp over the length of the cylinder head. I have personally witnessed Mr Toad fitting end caps in seconds!

If you want to stop your oil leak and protect the end of your camshaft from rusting at the same time, I'd recommend fitting the end caps as specified by MG Rover.

Simon

[Randyjim]

Originally Posted by SD1too

I'd recommend fitting the end caps as specified by MG Rover.
Simon

I have considered this, as they appear to avoid sealing against the camshaft itself, but the fact that 2 respected specialists have elected not use them during the last 2 belt changes raises the question of "why not?"!

[vitesse]

I’ve used cam seals rather than caps after hearing lots of distressing stories of flying cam caps. Simon refers to "specified by MG / Rover" - yes when the engines were new and blockage of the crankcase gases was yet to happen, but as I and many others have experienced the crankcase ventilation system is flawed.

Simon is quite right again, the caps don’t fall out but rather fly out under pressure and the owner hasn’t much time to prevent a fatal loss of oil. Even if the owner catches the oil loss in time, he then needs to replace the cap and refill perhaps five litres of oil - not much fun or chance at the side of the road.


A mechanic at what was our local dealership got so fed-up with caps flying that he developed a special holding bracket which he fitted to every engine in for belt changes.

Still each to his own, but I note that DMGRS now supply seals rather than caps as standard.