: 1998 Deville has leak at water crossover (150,000 miles)

02-03-14, 01:00 PM
The water crossover has a leak that drips on the driveway. I need to replace the 4 gaskets on the water crossover. I know this is a fairly big job, but my main concern is... how likely is it that one or more of the 8 crossover bolts are rusty and will break when I try to remove them from the water crossover?

Or any other advice? what about putting those "stop-leak" tablets in the coolant? this is not a typical minor leak, but maybe about 1/2 pint leaks out per day. I heard most mechanics say they dont like doing this because it can plug up the radiator and make the engine run hotter.

Note: I only plan to keep this car until this summer (which is why i cont want to pay the dealer $1000 to fix this)

Many thanks for any advice!

02-03-14, 03:04 PM
We agree with "most mechanics", however your car came with those sealant tabs from the factory and may have had them replaced several times with coolant changes as GM did not quit using or recommending them as regular maintenance until about '02. Judging from the size of the leak as you describe it, it may be too big for sealant tabs to work.

02-04-14, 08:34 AM
Id replace the gaskets, as much of a pain in the ass this job this is(i removed mine before), it's not impossible, with the right documentation at hand.

02-04-14, 03:27 PM
Yea, I was looking at the manual. I can understand most of the instructions... but do I REALLY need to remove the throttle body? I can understand why I need to remove the other things, but maybe when I get there, I will see why. But from what I see, I may not have to remove the throttle body. The air intake, EGR valve (EGR hoses) and the MAF sensor, yes... but throttle body?

What about removing the bolts from the throttle body (to separate it from the intake manifold), but not removing all the cables? and lift it up (about 4 inches) and hold it out of the way with twine.

Again... what about the 8 bolts holding the crossover? How likely are they to be rusty and might break when I try to remove them? Has this happened to anyone or any other things I need to watch out for?

02-04-14, 03:30 PM
The TB will be in the way when you go to lift the crossover out. You could leave it connected, but it'd be easier if it were out of the way. When I did mine, I removed EVERYTHING from the area, and took everything off of the crossover to make it as small and easy to maneuver as possible, and it was still tight.

I wouldn't worry about rusted crossover bolts. There's sealant on them, they should be fine.

02-14-14, 10:57 AM
Well, I got everything out of the way (throttle body, etc...)... but the wires that go to the PCM and the fans, etc... were in the way of the bolts to take out the crossover. So I gave up and put everything back together. BUT, I was able to tighten 4 of the top bolts of the crossover and the leak has been reduced by about 90%. I will add "stopleak" to the coolant and see if that helps with the other10%.