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Q: Leaking Water Pump Housing, the Plastic elbow from L Manifold to WP Housing. on 1998 Buick Regal

1998 Buick Regal 3.8L (Non Turbo) I just replaced the upper plastic Intake Manifold/Plenum section due to both flooding of the manifold internally and hydrolocking of flooded Cylinder #6. And after fully completing the job sucessfully and of course refilling w/ all fresh coolant, I noticed I still have a coolant leak that probably was the cause of the entire issue leading to previous loss of coolant and that manifold issue.

The leak is in a plastic 90 degree fitting (left end where it enters the water pump housing, not the lower manifold), that is on top of the water pump housing (crank dampener end of the engine), behind the multi accessory belt, above and to the right rear of the water pump pulley),that goes between the front middle of the lower Alum Manifold and the main water pump housing and it is leaking where it goes into the side of the belt tensioner part of the water pump housing.

My real questions are: Are there "O" Rings on each end of that 90 degree plastic fitting or is it glued or screwed in place? If glued in place, on which end is it glued, manifold or water pump housing, or both?

Best way to tackle that job?

Is that 90 degree fitting a part of the water pump housing, or a part of the lower intake manifold, or a totally separate piece w/ just an "O' Ring on each end?

Lastly, what is the actual name of that fitting? So when I do tackle the job here I know what part I'm actually looking/asking for.

TY for your time in answering. Your time is "Fully Appreciated."

As I can see and reach all the way around where that fitting is leaking and given the fact that there are many other cheaper ways to cheat and accomplish sealing that up w/ high temp epoxy, JB Weld or the like, and I do know what a job uninstalling/reinstalling that water pump housing must be to simply change out a possibly shrunk or dried out leaking "O" Ring, I was/am highly tempted to go that way. But, I realize that fitting is under at least 14 Lbs of pressure and more when the water pump is spinning.

I would much rather do the job right the first time and not have to worry about it further leaking as I live in a very hot climate and it just reached the century mark w/ a long hot Summer right around the corner, and I often drive long distances in the extreme heat out away from many services for miles on end w/ the A/C going full blast.

Thanks again.

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Google youtube enter 3.8 GM plastic bypass pipe look at video. Remove battery neg. cable before starting work! Not a major repair if handy with a wrench, seems you are. Get parts at GM dealer, better part and price!! Fixed a parking lot full of these. To save you and me some typing and time go to youtube, pretty good instructions. Been a bunch of intakes that got the blame for this leak!
TY much....It looks exactly like I thought it would on the ends, "O" Ring sealed each end, but was a much easier job than I expected.

I originally thought the whole water pump housing needed to come off to replace it, but removed the alternator and 3 other simple bolts, bought a stinking plastic $4.00 part, a little working the part back and forth to remove it, and a smidge of vaseline to allow those new "O' rings to slide in nice and smooth just like when installing a fuel injector, and a lil minor gentle cleanup inside 3 smooth bores first, and done in less than an hour. (I will say though the previous one from the manifold to the heater bypass had broken off long ago right at the "O" rings on each end, so I had to very carefully pry out both broken off ends from inside the bores and then remove a slag like chunk of cast iron from inside of the long bypass bore that was stuck at the bottom (lucky I had a 14" screwdriver), looks like from the internal engine block cooling passage somewhere (1/4" around, but heavy like cast iron and rusted up, probably been there since it was manufactured new).

No wonder both ends of that plastic 90 leaked though, it was just wedged there broken but held in place due to being a 90 and deep enough in there. I can't understand why Dorman hasn't made an aftermarket cast Alum. 1 yet (both bores it fits into are alum., so no chemical reaction issues should present there, and the other end is an alum 1), maybe because it is also the alternator mounting bracket? Electralisis issues possibly?

That upper manifold plenum though was flooded and cyl #6 was hydrolocked. So it wasn't just that leaky bypass pipe that caused that whole situation as there was plenty of coolant inside the plenum. Bad original design of that old EGR tube, and the seals did fail, especially at the lower side of the throttle body as it sucked it in from there (and now after looking at the class action settlement, looks like Dex-Cool is the real culprit there as it is now known to affect longterm the silicone seals upper/lower manifold/throttle body/ and the "O" Rings on that pipe, and really sludges up too. I saw lots of that when doing these repairs, so I also flushed the whole system and will a bit more often now. New Dorman Upper Manifold/Plenum has new EGR riser and alum shield and a 1/4" air gap completely around it. Plastic auto cooling parts sure suck, but Dex-Cool sucks even more I found out.

Repair Results: $3.99 at auto Zone (1 of the 2 in the dorman Help pt.#47065 pkg. fit the Manifold to bypass side, and the other one in the pkg. had the "O" Ring I needed for the Alum. 1 on the left side. Job is complete w/ no more coolant leaks. Too bad this all did not happen in the first 7 years or at least by 2008 (deadline to file a claim concerning the Dex-Cool settlement and before GM filed for bankruptcy. It was all covered in a class action lawsuit I knew nothing at all about. See; www(dot)dexcoolsettlement(dot)com for more info. Of course replace the 2 (dot)'s w/ periods. At least they had the settlement correct 150,000 miles limit or 7 years (whichever comes first)....Mine failed at 147,000 and change, and the 15th yr. Go figure.

Well, time to quit the book....Sry for the length, but others may need the info too....Parking lots of others like you said. I do wonder though if anyone has ever switched coolant type even though Bankrupted Government Motors (GM) says to only use their super wonderful damaging Dex-Cool in these particular models. Their multi hundred million $$$$ settlement tells me otherwise & I should try it.

I will never buy a GM product again (and I own 2 of them), as this set of issues results could have been much worse than $400.00 parts (Starter, ign. switch & harness, tow, upper manifold kit, plugs, bypass 90 kit, and misc. other parts, plus my labor...if during that hydrolocking of #6 cyl, that block, pistons had cracked, head gasket blown, etc.. Only thing that saved it was it let go while parking it instead of when driving at 75mph.

TY again for your great direction. It saved me much time and effort. And I appreciate it bigtime!
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