powpowj

I just finished my winter project. Intake manifold refresh There is a 6mm hex bolt that holds down the fuel divertor and the air box on the driver side. I dont want to over tight, but when it comes to temp it starts leaking coolant. The air box bracket first, than divertor bracket and just tighten but cant fix leak please tell me whats wrong thanks 89s4

worf928

Your problem bolt not only fastens the bracket for the air box and fuel pressure dampener, it is also one of two fasteners than fasten a cover plate the head. Under that cover plate is a paper gasket. So... possibilities:
1) The paper gasket is dead (usually they reseal but...)
2) You have the wrong bolt (too long) in that hole
3) There's crud in the bolt hole that's preventing it from turning in all the way.
4) You're missing the washer for the bolt. (Pretty sure there's 'posed to be a washer.)

Investigate in reverse order of the above.

EDIT: If the bolt is an Allen bolt (Porsche went to Allen bolts sometime between '89 and '91 for that bolt) then it may not have a washer. (I'm going to go check... hang on..)

worf928

No washer if it uses the Allen bolt.

Also, since two bolts fasten that cover plate, the other bolt could be loose. One's 22mm and the other is 25mm. That 3mm makes a difference.

powpowj

during this project, every bolt and screw was bagged and labled. so i know its the right one. I do not have a gasket My bolt does have a flange on it Do i need a gasket?

WallyP

Yes. It's not a critial gasket, so you can make from good paper, such as a manila file folder. Gasket paper would be better.

worf928

A flange bolt? Or a washer with a hex bolt? If the former then I'll bet you the bolt is the wrong length 'cause Porsche didn't use flange bolts in that location so someone lost a bolt and replaced it with something that was 'about' right.

You have a gasket. You probably didn't remove the cover plate - since you don't have to remove it for the intake job - and thus you didn't know there was a gasket. This gasket usually isn't a problem.

Is it leaking coolant from around the bolt head? Or from the seam between the head and cover plate?

In any case, pull the bolt. Measure the shaft length, clean out the bolt hole, measure the bolt hole. It is very easy to get crap in that bolt hole and I've found a 25mm over-tight bolt in that hole (done by other folks) rather than the spec 22mm bolt often enough to know that it is possible to think you have the right bolt in that hole when you don't

powpowj

im getting ahead of myself the bolt does not have a flange but a washer. the coolant is coming out of that hole the 6mm allen bolt goes into

worf928

OK.

If you are turning that bolt to the point where it is very tight and it is still leaking from around the bolt, then it has to be the wrong length bolt, or there's something wrong with the bolt or hole. (Crud, threads, etc.)

Pull the bolt, clean out the hole, check the threads, and check the length and depth. If you find that the depth and length are the same, then the bolt is too long.

powpowj

the 2 brackets its holding down doesnt get tight when i tighten the bolt there is movement from these 2 brackets So i know its not tight its a 22mm in length

jthwan22

how about tapping with metric tap to clean out hole?

Mrmerlin

just checked the PET.
For the rear block off plate and water outlet, it calls for 3 8 X 25 and one 8 X 22, so make sure that this shorter screw isnt holding any other parts except the cover.
If the bolt wont screw down all the way then a tap should be used to chase the threads.
Also check and see if there might be a snapped off bolt in the bottom of the bolt hole

Bill Ball

You're are wise about not over-torquing that bolt - I've seen the threads in the head stripped by doing this. I think the correct torque is about 15 ft-lbs.