gearz

I'm trying to remove the water bridge so I can get to the oil filler and fix this insidious leak.
The intake is in place. The drivers side rear M8 allen bolt would not come out despite my best efforts. Of course the readily accessible 3 broke nice.
I really don't want to have to remove the intake so I can remove the water bridge so I can remove and seal the oil filler..... So it seems the simplest thing to do would be to drill out the bolt head but I am wondering if there is enough overhead clearance to pull the bridge off the stud as it looks like it has to go up a ways to clear the insert into the block. It will not be possible to drill directly in line with the bolt so the full shaft will be up into the bridge after the head comes off and the housing base is pretty thick. Anybody done this?

SeanR

I tried drilling the head off one time for that bolt, won't work, you'll have to at least loosen the intake to give enough room.

borland

Removing the intake is easy. Those reseals your planning, are a normal part of the S4/GT/GTS top end refresh, where you address other common problem areas, like the idle control valve, knock sensors, & breather tubing.

Stromius

Must be the PNW rain...I have the O ring & gaskets on the waterbridge to do too. As said, the intake isn't hard to remove. Since you already removed the front fuel hose and fuel damper, just continue to remove the fuel rails and follow the many write ups for intake removal. Have you tried to use PB Blaster on the rear bolt?

Also is there any reason why these 4 bolts (M8 70 & 3 M8 35) have to be Allen heads versus normal bolts anyways?

heinrich

Gearz...

You do not need to remove the intake. You will need to treat that bolt like any other stuck bolt. You have the following options:

1) use PB Blaster or better (NOT WD40) and let it soak
2) insert a long allen wrench after heat-bending it just enough to fit into the bolt. Make SURE the allen wrench is squarely seated in the bolt head before turning and DO NOT USE a ball-end
3) If the bolt feels like it may not come out with the allen wrench, you will need to cut the elbow off it and hammer squarely (hence bending only enough) and ferociously to try to break the bolt loose
4) then try to loosen it again
5) if you do it right one of 2 things will happen ... it will come out or it will twist off
6) if it twists off, you pull the intake and properly drill and tap it out.
7) Either way, properly chase all threads unless they are already super clean
8) use silicon thread sealant next time
9) use new bolts only, and use the toughest hardened ones you can find
The reason this happens is one:

PO's often do not instal the factory seals properly or try to skimp and use silicon. THen, coolant gets into the threads and locks the bolts in-place

Btw is that Dave H's old car? And is that Louie's GT next to you in your avatar?

heinrich

Yessir. To access them from above in tight space. Makes no difference, non-abused allen heads are better than hex heads.

gearz

The intake has never been off on this car, I'm certain of that. I will use antisieze when I reinstall the bolts and sealant.
I don't think this is Dave's old car.. And that is Louie's car--picture was at the San Juan Concours this year.
I used PBlaster with heat and tried a ball end allen as that seemed like the best approach given the angle. Never thought of bending the wrench to fit. Wish I would have thought of that. I'm afraid the damage has been done as the head is stripped somewhat now.
Looks like I will be pulling the intake very soon.

gearz

Thanks, for some reason I figured that was a bad idea.

Fogey1

The best penetrating oil is half and half acetone and ATF.

Substantially, and measurably, better than Kroil, according to the machinist mag link Wally posted and I can't find. And cheap. And available.

Good luck,

Will
83S

Schocki

Hope that helps a little (from Dwayne): http://dwaynesgarage.norcal928.org/f...aterbridge.htm

Stromius

Nothing like a little PNW sun to do a small project. I tried and subsequentally failed to get my waterbridge bolts (2 back ones - 70mm & blocked 35mm). The 70mm rounded out and the other too blocked. I have a leaking O ring that I finally wanted to deal with.

Plan on a return to the scene but was wondering Gearz did this resolve for you and if so how did you get the bolts to budge?

I plan to:

1. Remove intake for better access.
2. Slot rounded allen bolt for a big *** flat blade screwdriver
3. Apply heat and yet more PB Plaster

gearz

The stuck bolt was easy to remove after I removed the intake. I heated it up with a torch and used a big *** pair of vise grips and it popped right out. Slotting it would have been next I suppose. In retrospect I'm kind of glad I stripped the bolt and wasn't able to get the water bridge off to get to the leaky oil filler as it provided me the impetus to do the full on intake refresh.