Piston rings and oil types

[cl25]

Hello All,

This is really my first post. I've been a member a while now but am in need of a few pointers.

I have a 96 X300 4.0 SWB with 174k on the clock. It does unfortunately have a little bit of smoking problem. The car drives nicely and doesn't seem to be missing power but when left to rest idling after a run slowly starts to smoke. If left for too long im sure I could create quite a smoke screen.

It is using 0W-40 synthetic Mobil oil and I'm wondering if it might be time to change the grade of oil as the engine is now getting older. It does seem to be using more oil than normal. Any thoughts on grades of oil?

I have taken it to Racing Green, near where I live and they came up with the same thoughts of me. Valve stem seals and possibly piston rings. Now I have never rebuilt an engine before and am willing to put the time in but can not find the piston rings for my car. Nobody seems to sell them anymore, is this right? What have other people done to resolve this parts supply problem?

I really like my car and want to do the right thing and repair it correctly but need a bit of guidance on where to look for these parts. I've tried David Manners and SNG barratts, both came back with a no. Any thoughts would be helpful. Maybe an engine rebuilder??

[ptjs1]

cl25,

A couple of thoughts:

All the specislists I've spoken to have always said to run an AJ16 Engine on 10w-40 semi-synthetic. I'd have thought 0w-40 was too thin.

As regards piston rings, you can buy the 0.02 oversize rings for the 4 litre from Jaguar still. Just look on the parts website. However I would have thought that any engine reconditioning company could source you standard or oversize rings.

Good luck

Paul

[J44EAG]

A couple of ideas for you.

If the engine starts quickly, you are likely to have reasonable cylinder compression which points to piston rings in fair or good condition. A compression test would confirm one way or another.

Releasing the oil filler cap when the engine is hot and running is a quick way to ascertain if the crank case is being pressurised by combustion pressure blow by caused by worn rings. If the engine pumps out clouds of oily smoke then that does indeed point towards worn rings. Oil leakage in excess from the front crank shaft seal will also give some indication that pressurisation may be present. It is worth checking that crank case breather pipes and their venting arrangements are not chocked with sludge or hardened deposits. A blockage is not desirable.

Valve stem seals and other seals such as crankshaft seals may harden in service due to age and heat. I`ve had this situation on my 02 plate V8 which suddenly started using an increasing amount of oil. The rear crank seal was also showing signs of leakage which on the V8 is quite a rare occurrence.

Faced with having to change a crank seal, I read a few internet posts and decided to try some magic in a bottle. I dropped in a can of Wynns stop smoke and seal rejuvenator fluid into the oil and drove the car for a few weeks. This stuff takes a while to do what it claims on the tin and to my astonishment, my oil consumption reverted to its normal levels AND the crank seal stopped leaking. Wynns claim the additive will help rejuvenator hardened valve stem oil seals. It does not affect oil viscosity or protection levels.

For around £6 a tin, it must surely be worth a try. It might just save you some dismantling and rebuilding work. If it doesn`t improve the situation, its only £6 shelled out. If it does work, you are quids in.

http://www.google.co.uk/url?sa=t&rct=j& ... GU&cad=rja

http://www.google.co.uk/url?sa=t&rct=j& ... GU&cad=rja

Mike K

[naki]

good advice there. i would certainly be inclined to try using 10w/40 oil. i have used this on al my AJ6 engines. you may also want to consider Castrol GTX 10w/40, as apparently it has a built in seal rejuvenator.
i worked well to reduce the effects of worn valve stem seals on one of mine.
i think an professional engine rebuild would set you back over £1000 i suspect, so worth a shot at these other options first

[J44EAG]

The thing about the rejuvenater I used was that it states clearly that adding it to your oil will not affect either flow characteristics, protection levels or viscosity. So in respect of any changes to oil properties it is for want of a better word, inert.

Whist I am fairly cynical about what we might cll magic miracle cures in a bottle, some do in fact do what it says on the box. I have three favourites which I know to be effective through experience. I am confident of their performance and have no hesitation in recommending any of them.

Firstly, the oil seal rejuvenater as detailed above.

Secondly, K-seal which is highly effective at stopping coolant leaks which may be elusive. It does not sludge when in service within a coolant system, is used by the AA and works very quickly and effectively.

Third on my list is Cataclean which helps clean catalytic converters and has been known to clear a fault code and MIL light if a cat gets blocked or has become restricted. Just had my latest MOT test today and emission levels have reduced after using the product when compared to my emission levels last year.

Mike

[oldtimer]

A compression check may be a good starting point.

You do not mention your mechanic ing skills or experience. The proposed engine strip and rebuild is a formidable task that you are contemplating. You never know what you may find when opened up, be warned it is never what you expected.

An oil grade upgrade is a first and must. Then follow the suggestion made by Mike and Co.

Give very careful consideration to the idea of a D.I.Y. job, in terms of knowledge, equipment, facilities and of course overall cost.

Do let us know what you decide and progress of course

Oldtimer

[cl25]

Hello All,

Thank you for your advice. The car starts pretty much instantly, albeit with a little screech from the starter motor when cold. I did what J44EAG said and found there was a little bit of a oil smoke, but only a little. It doesn't seem that bad for an engine that's done 174k.

I went a head and did an oil change, I put in Mobil 1 Extended Life™ 10W-60 http://www.mobil.co.uk/UK-English-LCW/c ... 10w60.aspx. I was recommended it from a guy who rebuilds XK engines.

I also put in some Wynn's Leak Stop when I did the oil change. I've run the car for about 2000 miles since the change. It seems to be running smoother and quieter, the oil level has not needed topping up and most importantly it has stopped smoking when left to idle.

Now just need to sort out the foot well...slight hole in the passengers side.

[naki]

great news. thanks for the update.
I bet you are glad you asked here before going ahead with a rebuild!