Engine Rebuild?

[chrisjcoe]

There was a fair bit of white smoke on start-up today, and I ran it for a few minutes and noticed a slight oily smell, although I couldn't see any blue smoke from the exhaust. Combine this with a small oil leak (a few drops left behind recently) which I had to top up the other day, and my proposed engine refurb looks like it may be brought forward somewhat! Being a total amateur, here's the plan so far.

I was going to get the car up on stands to identify where the leak is coming from, but I'm hoping this is just a seal/gasket problem and possibly related to the smoking. I also hope that buying a head gasket set and cleaning up everything I find when fitting it is what the car needs. Reading up on some of the excellent engine threads shows this isn't a quick or easy job, and also shows you could find a load of nasties along the way.

What else would you lot advise/recommend? Would you do a compression test first? Would you also fit the cam gasket set? While I was there, how about the full belt kit?

Due to the smoke, I plan to mothball the car for a while, so no more fun weekend drives []. That's my incentive to get moving on fixing it though

 

[bighead]

I would first to a compression test to see the state of the engine and if its is making good compression all that its require will probably be the fr/rear engine seals and head gasket .

mine weeps a little oil from the fr and rear seals but i never need to top it up in one year's of ownership...but i drive it only as a third car though (less than 1k miles year) .

always good to the other jobs "while yr in there ">

 

[bmnelsc]

White smoke is usually water getting into a combustion chamber so it is probably a head gasket issue (could be worse but that is a good assumption to start with). A compression test may show low compression on one cylinder or two adjacent cylinders if the head gasket is leaking water into the combustion chamber(s). Low compression across the board suggests worn rings or valves or both. If a little oil squirted into the cylinders improves the compression - it is most likely worn rings - if no improvement then is likely valves. Note that neither of these conditions will cause white smoke in the exhaust - you still have a leak somewhere.

To replace the head gasket you need to remove the cams (so new gaskets and cam seals here) and belts so you should plan on doing belts and rollers and unless you can prove a recent water pump you may as well change that along with the front seals. And seeing as you have a twin cam engine - you should be looking at the cam chain and tensioner - the plastic guides probably could be changed.

Rear main seal is a different beast altogether as you need to remove the clutch and flywheel to access the seal (means disconnecting and sliding the trans-axle back about 4 inches).

 

[zcacogp]

Suggestions;

1. Do a compression test. Report back with the results.
2. Monitor oil usage. Does it use the stuff? Is this due to leaks or burning?
3. Is there a build-up of white gloop in the oil filler tube and under the cap?

If the answer to the last two is 'No' and the first one gives good results then I wouldn't spend the time and money on rebuilding it - it's quite a big job.


Oli.

 

[chrisjcoe]

Thanks guys

Going to get a compression tester and post the results here. Is this one more than adequate for the job? I can buy cheaper online, but I can pick this up tonight.

I've read/seen conflicting information about performing this test. I've seen a few people remove all the plugs, then attach the tester and turn the engine over. I've also read that you are supposed to disconnect the ECU, take a single plug out and attach the tester before turning it over. Clearly the goal of each is to prevent the engine from firing, just cranking it over. Is one approach better than the other?

I'll need to get a spark plug socket and wrench too, what's a good value option here?

The underside of the oil cap was clean. I haven't checked the oil filter tube and don't plan on changing the filter just yet. I also won't be running the car, I don't want to damage the head or anything.

 

[zcacogp]

Chris,

That bit of kit should be fine. As long as it can reach down the deep spark plug tubes that the S2 has then it will work.

Procedure; remove all four spark plugs. Remove king lead from distributor. Put compression tester in hole for cylinder #1. Crank engine, take reading. Move to cyl #2, repeat. Go on to #3 and #4. Compare readings. As long as they are all within 10% of each other, and no two adjacent cylinders differ by more than 5%, then you are OK. (It is worth comparing with the 'correct' results from the compression ratio, but unless they are seriously down then don't fuss too much).

There should be a spark plug spanner in the tool kit. If not then you'll need to buy one, but it needs to be deep enough to get down those tubes and narrow enough not to foul on the sides. I use a Teng socket set (excellent brand), but it's worth trying whatever socket spanner you buy for fit before spending cash on it; I know that some just won't work.

Ummm, don't take this the wrong way but you don't sound like you are that mechanically-minded. Would you be thinking about doing that potential re-build yourself (££ on parts from supplier) or paying someone else to do it for you (£££ on parts with extra mark-up and £££££ on labour)?


Oli.

 

[chrisjcoe]

Ummm, don't take this the wrong way but you don't sound like you are that mechanically-minded. Would you be thinking about doing that potential re-build yourself (££ on parts from supplier) or paying someone else to do it for you (£££ on parts with extra mark-up and £££££ on labour)?

Lol, don't worry about it. I've never tackled anything big on a car before, but bought the S2 to learn. I was planning on sorting the basics out before anything big, but the latest issue has forced me to bring my plans forward rather rapidly, before I'm properly prepared with the right tools. I've always found that taking things apart is the best way to learn, and with enough documentation, forum advice and a friend to call who builds his own track cars, I'd hope to learn pretty quick. Also, I really couldn't afford the £2-3k for an engine rebuild.

There should be a spark plug spanner in the tool kit

Hmmm, the car didn't have one of them! I'm assuming I'll need a deep socket depth, which means my current set won't cut it, so another thing to add to the shopping list.

 

[edh]

As well as a (warm?) compression test it might also be worth getting a friendly MOT tester to check your expansion tank for exhaust gases. You might even be able to smell them.

When the H/G went on my turbo (the first time) i didn't get any oil/water mixing, or oil in the cylinders, but I did get coolant in there, which actually resulted in the coolant being pressurised & blown out of the expansion tank via the overflow pipe.

you might find that the white smoke was just because you started the car up on a cold morning.

 

[chrisjcoe]

you might find that the white smoke was just because you started the car up on a cold morning.

It was Sunday afternoon, not particularly cold and not damp. The car is parked outside and in the shade. There was a bit of an oily smell, even after running it for 10 minutes, although the white smoke stopped not long after starting once the engine splutter had died down into that usual Porsche noise we all love. I'll definitely do a compression test before anything else. I have considered taking it to my local mechanic to give it a once over, he should spot any obvious problems on top of the ones I already know about. I've also asked my track-car mate to pop over and look around it, although he's notoriously difficult to pin down!

 

[edh]

At this stage the main thing is not to over-diagnose - internet forums are full of cars with problems & it's easy to convince yourself that yours is suffering all of the same issues

Try whipping off the expansion tank cap (when cold) & having a sniff

This is the compression tester I've got - works fine

http://www.halfords.com/webapp/wcs/..._productId_199553_langId_-1_categoryId_255216

The machine mart one seems to have more bits & pieces but I don't see why it wouldn't work

 

[zcacogp]

ORIGINAL: edh

At this stage the main thing is not to over-diagnose - internet forums are full of cars with problems & it's easy to convince yourself that yours is suffering all of the same issues

... and that, Boys and Girls, is perhaps the most sensible thing I have ever read on an internet car forum.

Well said Ed. Wise words indeed.


Oli.

 

[chrisjcoe]

quote:

ORIGINAL: edh

At this stage the main thing is not to over-diagnose - internet forums are full of cars with problems & it's easy to convince yourself that yours is suffering all of the same issues

... and that, Boys and Girls, is perhaps the most sensible thing I have ever read on an internet car forum.

I hope you're right, not just for the sake of my wallet, but also because I wasn't planning on a gasket change and cleaning up the head until spring!

Don't worry, I'm not rushing out to buy the gasket kit or any other parts I probably don't need, but all the information about what could be wrong is useful, giving me an idea of the type of scenarios, outlay and tools I may be dealing with. I must admit, my thread subject title was a bit worst case, typed on a Sunday evening after a few whiskeys and annoyed about not being able to enjoy the S2 for the last few nice weekends of the year!

All advice you guys give is appreciated and listened to 100%, otherwise I wouldn't ask! If any job is beyond me, I will have it done professionally. If I'm not sure of anything, I will post photos here for you experts to look at before telling me the good/bad news.

 

[zcacogp]

Chris,

Good - that's a sensible outlook.

Do a compression test, and post the results on here. So, compression in the four cylinders, by cylinder.

No gunk on the back of the oil filler cap? Good news. And you'd notice any gunk down the oil fill tube when you put any oil in there, so there probably isn't any.

My suspicion would be the white smoke is from a cold start-up and nothing more. But that's only a suspicion; give us those compression test results and then we can tell you whether to worry or not!


Oli.

P.S. I notice you are in Colchester; there are other folks from on here in that neck of the woods. Should you need someone else to have a gander then ask around ...

 

[chrisjcoe]

My suspicion would be the white smoke is from a cold start-up and nothing more. But that's only a suspicion; give us those compression test results and then we can tell you whether to worry or not!

Thanks Oli, that will help a lot. Tonight/tomorrow I'll get a compression tester, and the right tools to remove the plugs, so I hope to post the results later in the week. I do have Thursday and Friday off as the girlfriend wants to go for a couple of days out, so if I don't get round to it beforehand, I could risk a bit of an ear bashing by doing it then []

It's been rough on start-up a few times lately, Sunday was bad though. Once it ran smooth I drove it for 10 mins, let it rest for 45 minutes, then started it again. The 2nd time it started fine, although I was aware of a smell of fumes but that could just be because the drivers side boot latch has decided it no longer want to stay shut!

I'll update you in a few days

 

[chrisjcoe]

Good and bad news!

Compression tests were (from front) 175, 175, 175 and 172 is the good news. The bad news, all plugs were black with soot and the 2 plugs nearest the driver were oily. I photographed them on the oily kitchen towel and will post the photo later. The threads were where most of the oil was, and there was evidence of a bit of oil escaping too.

When the engine was turned off I could also hear a faint hissing type sound from around the head for a few seconds. Any idea if that is normal? Sounded like a very faint kettle boiling. The coolant is low and waiting for a top up by the way.

 

[zcacogp]

Hmmm, those are very good compression results, for sure. Nothing to worry about there.

Sooty plugs and fume-y smell (and indeed rough running as well) could be explained by poor mixture. Have you had the emissions checked?

Hissing sound after the engine has stopped could also be simply the compression in one cylinder near the top of the compression stroke leaking to atmosphere, possibly through a slightly-open valve.

When you say the coolant is low, do you mean it is below the 'Min' mark on the header tank? If so, don't worry about it; my S2 will regularly throw out any water from the header tank until it is some way below the 'Min' mark, and apparently this is quite normal behaviour.

Have the emissions checked (turn up to your local friendly MOT place when they are quiet, ask them to check the emissions and bung 'em a fiver - it'll take them five minutes.)


Oli.

 

[chrisjcoe]

Good idea Oli, I'll see if I can get that checked. Is oil on the plugs any cause for concern?

Yes, coolant is below min, asda do a phosphate free coolant which I might pick up tomorrow for a little top up

 

[Hilux]

Do dry compression tests first as this tests the valves and rings then pour a little engine oil into each chamber so it seals the rings and do it again as this tests the rings against the valves and let us know the results.

 

[chrisjcoe]

ORIGINAL: Hilux

Do dry compression tests first as this tests the valves and rings then pour a little engine oil into each chamber so it seals the rings and do it again as this tests the rings against the valves and let us know the results.

Thanks, I'll do that tomorrow. Presume tests are on a warm engine

 

[Hilux]

No not necessary, a cold engine will allow the maximum tolerances whereas a warm engine will have the the tolerances closed up so will show better readings.

I tend to remove all the plugs when turning over (or loosen the ones on the cylinders that arent being tested) as oil can get thrown up but remember to clean oil off them.

As an aside - if the plugs are sooty it might be 1) that its running rich - better rich with a turbo than lean [] or 2) the plugs are rated as too hot ie: you need cooler plugs - check the plug type against recommendations from others on here.