Low compression on one cylinder - what to do?

[sacha]

Unfortunately my 2.2 N/A 1988 stevens esprit is running at 9bar on 3 cylinders and 3 bar on 1 cylinder. I have put some oil down the bore and carried out another compression test which shows 8.5, so i assume the piston rings are buggered on this piston. The question is

Should i remove the engine and change the rings on 1 cylinder

Change all the piston rings

Change all the pistons

etc etc

I think you know where im going with the above. Im just wondering what peoples suggestions are. The engine has just clocked 102,000 miles

If anyone has any ideas on what engine model mine is, what prices are etc that would be a great help

[andydclements]

102k. Surely it's had a rebuild during that, if not it's done well.

Did the compression change by putting oil down? If yes, then I agree with you thoughts- rings.

If no, then you have other issues.

Re the rings, all rings changed as sets as a general rule, but beware you could be looking at a lot more than that at 102k. Bores/ liners, pistons, big ends mains etc, if you start doing the top end up it will highlight any weakness in the bottom of the engine. that's not to say you will have these issues, just don't assume the best, or the worst, keep to mid budget and you will not be too far out.

Andy

[rogerch]

Personally speaking (I'm a known fanatic), I would pull the engine out, having spent 2 days doing that, I would reconcile myself to never doing it again. Strip the engine measuring all clearances as I go, but with 102K on the clock I would already know re-cut valves and seats, replace if necesary, valve guides seals, new liners, new pistons, head resurfaced, crank re-ground, new bearings, all new gaskets, seals, don't forget water and oil pumps, send the stater motor and altenator to the autoelectrician.

While the engine is out, remove inspect and flush the fuel tanks, may as well do the raidiators, cooling, oil, check and replace all the hoses, have I missed anything? Oh yes I put a sycro kit through the gearbox.

There again I've never actually done an Esprit, but I have done a couple of Elans, one engine all I salvaged was the Alluminuim casting of the cylinder head and the cam covers!

Roger And don't forget the clutch!

[Glyn Harper]

Ouch...

I'm afraid at 102k, if it's not had a rebuild I would suggest new pistons, rings and liners. Crank will possibly need a bit of a regrind as well.

All worth doing while the engine is out.. you don't want to be doing the job again in 6 months when one of the other pistons go!

The pistons are all matched by weight, so if you are on a budget you could just replace one.. but I would try and do all 4.

The liners are nikasil coated aluminium, so I suspect the nikasil has worn off by now.. and you can't buy pistons seperate from liners unless you go for aftermarket ones. (I wouldn't).

Also, there is a mod you need to do where you loctite the bottom of the liners in. People on the forum should be able to provide info, or request the buletin from Lotus..

There's loads of stuff you want to do while the engine is out really.. check valve clearances and change shims appropriately.. etc..

As yours in an NA, it won't be getting the same stress the Turbo engines get, so you may find when it's stipped everthing looks ok.. Just the pistons and liners!

You want to track down Gary Kemp if you need an engine rebuild and want someone else to do it. He builds some great engines. I know of an NA engine that ran at about 245 bhp.. It was in my friends S3!

[sacha]

Does anyone have a rough idea of cost for doing the full stripdown and rebuild. Leaving labour costs aside, just the parts cost

thanks for all the advice and responses