WICruiser

Last year I refurbished the intake including the coolant cross over and oil filler. New thermostat and internal seal in the cross over while I was at it.

Due a variety of other projects on the car it only recently became drivable. Initially every thing seemed fine but now I have a coolant leak. The leak appears to be from the cross over connection into the block, at least there is coolant pooled in the recess around that connection. All the hoses appear to be leak free but it is pretty hard to tell until I get into it.

Any other areas I should look at more closely before I dig in? I hate to pull the cross over only to not be able to identify the souce of the leak and start all over again.

Bill Ball

Yeah, doublecheck the clamps on the two small hoses that go to the bridge. I've left one loose at least twice. They will fill the same recess.

Mrmerlin

any chance the temp sensor is leaking? Are the hoses new or used might there be corrosion on any of the hose connections on the crossover, this might cause a leak if the hose connections have this corrosion

WICruiser

Thanks for the suggestions, I will check the hoses before I dig in and remove the bridge. It sure would be easier to fix.

Ted928

I installed new O-rings in my crossover last year and it is leaking. I took it apart today and it looks like the red O-rings are not fat enough. They do not protrude above the surface. I may have over tightened them last year. Anyone else have problems?

Thanks
86 928S 5 speed

Mrmerlin

get new red o rings.
they are not really round but rather oblong in crossection. with out any O rings on the crossover fit it and see whats causing it to not seat you may hev to sand down both sides of the crossover where it fits against the heads if the heads were cut down to much use some sand paper on a flat surface to do this. kind of file to fit. OR you could pull the heads and fit thicker head gaskets, but thats probably not gonna happen

Ted928

Thanks for the insights.
I ordered new O-rings but won't get them for a few days. The crossover is bottoming out against the heads so I don't think that is the problem. It just looks like the grooves are too deep so the O-ring sits too low. I may have over tightened the bolts since I don't remember torquing them a year ago when I installed them and I can't find a torque listing in the shop manual.
I'll let you know how the new O-rings fit. Thanks

Mrmerlin

do a test fit, use a feeler gauge to see what kind of clearances you have regardles of tightening, the seals should not have leaked if both surfaces were smooth/IE mated flat. Also look for cracks in the crossover hsg.