Help - your opinion needed! 85-525e blown gasket, or warped/cracke

[bigbertha 0]

Hello There,

Here's the relevant information, if you need to know anything else please dont hesitate to ask, I will really appreciate any input you all may have on this issue for me :-)

It started with a loud bubbly, splutter sort of sound from the exhaust, and an obvious drop in performance in the last 15 minutes of an hour long drive. I took it straight to a friend of mine to try and diagnose what the problem was, ive probably driven 20killometers total since it happened.

Its a 1985 525e and has been well looked after, e28 model with the M20 2.7L engine. The previous owner did an LPG conversion on the car which is handy

- Oil level and quality in engine is fine

- No oil in coolant

- The engine is not over heating - Ive been vigilant about keeping the engine cool

- There was some oil on spark plugs have now put new plugs in

A compression test showed

- Cylinder 1 - 225psi

- Cylinder 2 - 220psi

- Cylinder 3 - 70psi

- Cylinder 4 - 75psi

- Cylinder 5 - 215psi

- Cylinder 6 - 210psi

and also a leak test showed that air was escaping between Cylinders 3&4

So I am hoping that a new head gasket will do the trick but another friend of mine told me that 9 times out of 10 if the head gasket is blown, the head will likely be warped as well, not sure how accurate this is though?

I'm super keen to do the work myself so I can learn while I go, plus I am a student so I cant fork out the $2500- $3000 I was quoted to fix!! Beyond any general pearls of wisdom you may be able to offer, I would appreciate any links to useful resources or web pages, or forum posts that you think might help. Should I start dismantling to get the head off, or is there a further diagnostic test I can do on the engine first?

Cheers, Hans

[BM WORLD 1291]

i had a an engine like that once , blew the gasget out between 2 cylinders , but was not over heating etc.

just keep cutting back from 6 to 5 or 4 cylinders when driving.

should be ok , get the head off and checked , cleaned up etc .

can sort a replacement head if needed.

pretty easy job .

Edited June 18, 2011 by Brent HARTGE535i

[Steve K-B 51]

Yeah it sounds like the gasket is blowen between the two cylinders as above.

Take the head off and have a look at the gasket your self. Next thing to do is send the head away to check for warp and a crack test. Dosn't cost to much. Last time it was around $200 including the skim. Just find a local head shop around your area.

Ive done this plenty of times and only once have I had the engine block warp but as yours has not been hot i would be confident that its fine.

Edited June 18, 2011 by Steve K-B

[bigbertha 0]

i had a an engine like that once , blew the gasget out between 2 cylinders , but was not over heating etc.

just keep cutting back from 6 to 5 or 4 cylinders when driving.

should be ok , get the head off and checked , cleaned up etc .

can sort a replacement head if needed.

pretty easy job .

[/quote

Fantastic, thanks Brent, im glad to hear you had a familiar problem with your engine, after having a look at the picture you attached of the gasket im certain that my car has exactly the same issue, but between cylenders 3&4!

I will go ahead and take the head off and see whats going on exactly, and will let you know if im needing a new head (fingers crossed though)!!

Thanks again for your reply mate, enjoy your weekend,

Hans

[bigbertha 0]

Yeah it sounds like the gasket is blown between the two cylinders as above.

Take the head off and have a look at the gasket your self. Next thing to do is send the head away to check for warp and a crack test. Dosn't cost to much. Last time it was around $200 including the skim. Just find a local head shop around your area.

Ive done this plenty of times and only once have I had the engine block warp but as yours has not been hot i would be confident that its fine.

Thanks to you as well Steve, thats good advice, ill take the head off and get it tested, and machined if needed, Im assuming thats what you mean by "skim"?. Budget wise, im limited to about $400 at the moment, so ill be able to get it tested so I can know for sure!! Glad to hear your optimism about it just been the gasket and not a warped head, makes me feel better about choosing to not drive the car at all until I fix it!

[BM WORLD 1291]

its a good time do a head overhaul , valve seat grind ,skim the head test for cracks , warps etc new valve stem seals fitted about $300-500 for that lot done at a head shop .

new cambelt , water pump ,tensioner , all top end gasgets etc.

gasget set should be about $200-300 ,cambelt , water pump , tensioner $100+ etc

[bigbertha 0]

Im quite excited by the prospect of pulling the engine apart, well taking off the head anyway! I have always been intimidated by the engine for some reason, stupidity probably! No problem pulling the electronics, brakes etc to bits but never touched an engine, nervous excitement!

Are there any specific tools that im going to need beyond the normal, ive got socket sets and everything else you would find in an average tool box, but im sure ill need some specialist tools along the way?

Cheers, Hans

[BlowMyWhistle 0]

Head set from the US is about $150 Turners or Pelican.

[pureboiracer 0]

Im quite excited by the prospect of pulling the engine apart, well taking off the head anyway! I have always been intimidated by the engine for some reason, stupidity probably! No problem pulling the electronics, brakes etc to bits but never touched an engine, nervous excitement!

Are there any specific tools that im going to need beyond the normal, ive got socket sets and everything else you would find in an average tool box, but im sure ill need some specialist tools along the way?

Cheers, Hans

torque wrench and angle guage,

feeler guages to reset tappets when you put it back down, the head shop usually do this however it has been known to move when bolting down the head,

and possibly a torx socket set.