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Coolant by pass elbows leaking

12-29-2010, 01:59 PM
I have been lurking around for a while, but have a topic I want to see if anyone has done this. I have two Buick Regals, both have the 3.8 super charged. One has 175,000 miles and the other has 106,000 on it. I have replaced the coolant elbows at least three times since I have owned them. Both cars I have changed the intake gaskets on using GM,s new aluminum plate gasket. The problem I am having is after any where from 5,000 miles to 20,000 miles the coolant elbows start leaking. I have cleaned out the holes they go into very well, used grease on the o rings for installation. On the high milage car the bottom elbow started leaking after 20,000 mi, and on the 106,000 I changed the intake gaskets and the elbows this past summer and now that cold weather is here the top elbow is leaking. I am thinking about using silicone at installation on the orings instead of grease. Let it set for 24 hours then fill with antifreeze. Any comments would be welcome, good or bad.

12-29-2010, 07:30 PM
Please post the year of your Regals. Reason is '97-'98 and '99 and up are different as it pertains to the tensioner assembly and bypass elbows.

Are these GM bypass elbows or aftermarket?

12-29-2010, 07:45 PM
The cars are 2000 Regal GS. I have used both GM parts as well as after market elbo's. I was thinking about dealer parts or after market, but I thought that with the few being used they most likely came from the same mold. Molds like these are very expensive, but I have used GM parts plus I have bought them at different parts stores.

12-30-2010, 09:19 AM
I've had good luck with the GM/AC Delco elbows which come with the o-rings. See link below.

Click here (

Aftermarket elbows like the Dorman brand are junk and members had issues with them. Also, make sure you get all the broken plastic pieces, if any, out of the LIM, pump inlet and tensioner assembly.

12-30-2010, 09:33 AM
Thanks for the reply. I will try the GM parts again, may be I did not get the holes clean enough.

12-30-2010, 09:37 AM
Correct ,my Dorman replacements leak when the engine cools dow, PITA!!!

12-31-2010, 11:20 AM
I agree on the Dorman elbows, go with GM or you risk leakage.

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