Head Gasket.

[Gremlin]

Just been and collected the head from machine shop, it’s now a case of putting it all back together and with this weather looks like the Gazebo will have to go up, oh how I envy you lot with garages. Before and after pictures. The tolerance on the head they allow before it needs skimming is 3 thousand, mine was 6 thou bit like a banana. Valve guides were really good but the valve seats were pitted so the recut them for me. Then fitted new valve seals. Good job I took the head off as he told me that the camshaft tensioning spring was gone. As he showed me what he meant it popped out. That’s more money cam chain tensioner and guides now needed. It’s only money you can’t take it with you lol.

 

[Althulas]

Cleaned it up quite nicely. I hope the weather improves for you.

 

[Gremlin]

It’s taken 2 days and a lot of work but I’m pleased to say she is back together and started first time, only thing I’ve a problem with that will get sorted out tomorrow is the new front pipe onto exhaust manifold has a blow on it, not sure as to why yet. Run her up to temperature and have no water or oil leaks so I’m well pleased with myself. I will try and put a couple of pictures on tomorrow I can’t wait now to get her out and try her on the road. I can say this I have learnt a lot from this head rebuild about the Z3 1.9 M44 engine.

 

[Mazza]

Great job. You must be really pleased with the result.
Were there any special tools needed to do all this work ? ( other than the camshaft lock and that pertractor thing for torquing the head down)

 

[Gremlin]

Great job. You must be really pleased with the result.
Were there any special tools needed to do all this work ? ( other than the camshaft lock and that pertractor thing for torquing the head down)

No and to be honest I think now I’ve found out that if you take the head bolts down to snug at about 15 lbs then to 30 lbs leave them for 15 to 20 mins then take them down to 55 lbs is what I’ve been told. But I did mine to 22 lbs then 90 degrees left for 15 mins and then the last 90 degrees. I do find it a very unnerving proses though. And to get the head gasket to stay in place while you put the head back on is fun, with the lay over of the block.

 

[t-tony]

Are there not a couple of dowels round two of the head bolt holes to locate the gasket and prevent slipping? I have several pairs of "dowels" I have made for various engines over the years for just this problem. You can make them from a couple of the old head bolts cut down to 2-3" in length and a slot cut in the end to facilitate removal with a flat blade screwdriver.

Tony.

 

[Gremlin]

Are there not a couple of dowels round two of the head bolt holes to locate the gasket and prevent slipping? I have several pairs of "dowels" I have made for various engines over the years for just this problem. You can make them from a couple of the old head bolts cut down to 2-3" in length and a slot cut in the end to facilitate removal with a flat blade screwdriver.

Tony.

No there were none in the top of the block, so what I used was masking tape right across the very back and front edge of gasket. It will not stick to the type of surface the gasket is made of, so once I’d lowered head on and located it with a couple of bolts I just unstuck one end of tape from side of engine block and pulled it out. I must admit I like your idea wish I’d thought about that myself. ( good one Tony )

 

[mrscalex]

I've had a go at most things on a Z3. But I have to say doing a cylinder head would frighten me. So a very well done for tackling this job!

 

[Jack Ratt]

No and to be honest I think now I’ve found out that if you take the head bolts down to snug at about 15 lbs then to 30 lbs leave them for 15 to 20 mins then take them down to 55 lbs is what I’ve been told. But I did mine to 22 lbs then 90 degrees left for 15 mins and then the last 90 degrees. I do find it a very unnerving proses though. And to get the head gasket to stay in place while you put the head back on is fun, with the lay over of the block.

I couldn't understand why manufacturers now specify a tightening torque followed by an angular tightening sequence. I recently did the same job on my 2.8 and first tried to find a hire shop that stocked torque wrenches with the angle capability, needless to say I couldn't find one. I bought an angle gauge from Ebay but it wasn't very helpful as it was too bulky to use on the holes at the back of the engine. I bodged one together from an old set square.

I agree with your comment about it being an un nerving process though. Mind you, I helicoiled all my head bolt threads and I was worried about stripping them on the second run of angular tightening.

Hope your work is rewarded with a good runner. I finished mine, got her through an MOT but she was using far to much oil and I recently replaced the engine, so all my work was in vain, although to be honest I enjoyed doing it and like you learned a massive amount about my car.

 

[Gremlin]

Ref exhaust blow it’s not down to me, after rechecking all the manifold studs and nuts and checking the flange of exhaust to manifold before I started it and it got to hot to work on which was a pain in the A***, I then started her up she fired up straight away no hesitation but what a noise again, so underneath I crawled yet again only to find on the new exhaust front pipe right between thy Y- piece it had not been welded. Not a happy chap for 3 reasons
1st I’ve had to take it off again.
2nd I’d painted it with 3 coats of heat resistant paint.
3rd I’ve had to pay for another front pipe and send other one back under warranty which I thought was wrong, what’s stopping them when they get it back saying they can’t find a fault with it.
Ah there’s a 4th I’ve got to crawl under car again to refit the pipe tomorrow Grrrrrr.

 

[Mazza]

No chance of just getting someone to weld it???????

 

[Gremlin]

No chance of just getting someone to weld it???????

I did think about it but then thought if they blow a hole in it it would void the warranty. And I had no transportation to get it done partner is out all day with other car. It’s given me chance to have a check round underneath and paint the subframe thing I took off to get at exhaust manifold.
Oh yes the new sump plug went in ok and it tightened down ok but thanks for your offer.