Dont know how much more of this I can take

Post Mon Apr 10, 2006 8:12 pm

Stealth wrote:What's the best thing to do..

I have 1 more 90 degress to do, or whole new head gasket, or live with it..??

OK, I'm no expert, but if I was in your position.........
Do the final 90deg. Fingers crossed, the leak may stop. If the engine's running OK, leave well alone even if there's still a bit of a leak. If the engine doesn't run as well as you feel it should, then think about taking the 'head off and doing the job again.
Don't forget, if you do have the 'head off again, it'll need skimming again (providing there's still enough left on the face to allow it).

Mine's got a slight leak from the front of the 'head and has had since I had the 'head off 5k miles ago. I'd rather cure it, but I'm loathe to strip it again when it's going perfectly well, so I'm leaving it. It's not got any worse.

Don't forget, this is only my opinion. If you're concerned about your car, get at least one expert opinion to help you make up your mind as to your best course of action.

Stuart.

Post Mon Apr 10, 2006 8:16 pm

good advice mate.. When i did the first 90, and put the rocker cover back on, it ran a bit lumpy, but seems to of settled down a bit now, although i'm sure it's not as good as it was before the first 90..!!

I might just try a 45..!!

Post Mon Apr 10, 2006 8:22 pm

Oh.........
........ And bear in mind that there are allegedly very few oil tight M20's about.

Post Mon Apr 10, 2006 8:28 pm

Good point.. might just leave well alone.. and keep an eye on it.!!

Thanks again for the advice..!!

Post Mon Apr 10, 2006 9:05 pm

Did you guys check the head to see if it's twisted or bow'ed ?
I've just removed a 320 head from a perfectly good engine to find it has a convex bow on it

Stealth, have you used new bolt's ?
If you don't screw it down to the required tourqe there's no way that thing will last with the summer coming.

Post Mon Apr 10, 2006 9:15 pm

Hi Head is flat.. and i have used new bolts..

Just a pointer.. this is no my main car and only gets used the odd weekend.>!!

Post Mon Apr 10, 2006 9:32 pm

Martinaston wrote:Did you guys check the head to see if it's twisted or bow'ed ?
I've just removed a 320 head from a perfectly good engine to find it has a convex bow on it

Mine was skimmed and fully refurbed (all new gaskets, seals etc).

Post Mon Apr 10, 2006 10:24 pm

Stealth: you NEED to get those head bolts torqued up correctly or you're going to end up with some serious problems with effectively a loose cylinder head.

Best thing you can do is this:

Make sure the engine is STONE COLD

Gradually loosen all head bolts in the correct sequence but don't totally loosen them. Get yourself a new set of head bolts as they are only designed to be used once.

Then (in the correct sequence) replace the old bolts one by one and as you go tighten them to 30nm as per the first stage of tightening head bolts.

By doing it this way you'll keep pressure on the head gasket at all times and should avoid any leaking oil. Once you've replaced all the bolts, double check they are all at 30nm once again.

In the correct sequence, tighten all to 90 degrees. It's no good guessing what 90 degrees is, you need torque angle guage. Once you've gone round and tightened them all to 90 degrees, do it again a further 90 degrees. It will feel like you're about to snap the bolts off it's so tight but persist with it because this is the right way of doing it.

Do NOT run the engine during the job, it needs to be stone cold the whole way through as temperature will affect the torques due to expansion of materials.

Post Mon Apr 10, 2006 11:08 pm

He should be alright with the original bolts, as they've never been fully torqued yet.
If they've been done to initial torque + 90, then I think I would just do the final 90 and hope.
The bolts MUST be fully tightened.
After the initial torque, I always mark a line on the bolt heads with a permanent marker. Just to make sure that i don't miss one when doing the 2 X +90s.

Post Tue Apr 11, 2006 11:48 am

OK.. I'm confused..

Is it ok for me to give them one more 90.. it really feels as if they are going to snap..!!

I'm not too sure about replacing them, but it is a good idea..!!

Are they likely to snap.. and if i don't do the second 90 am i going to get into big trouble..?? don't want to blow anything up..!!

Post Tue Apr 11, 2006 1:05 pm

when i put my engine back together on my other car, i tried to do it as by the book as poss,
i ran the cam in,
stopped it - re-tightend everything
ran it for another 25 mins
then checked all the bolts again, and done tappets.

the first time it started the head was leaking water out the block and head join, and was seeping oil. but i wanted to run the cam in so just kept it going for 25 mins. it wasnt leaking bad.