The car belongs to a friend of mine. The engine is a 96 Buick Regal 3800 Series II N/A
Coolant is leaking from somewhere unter the throttle body, and running down across the thermostat housing, and puddling on the front side of the intake manifold.
Does anyone know the likely source of this leak?
Upper intake gasket? TB gasket?
Is it a straight forward repair? Any tricks that would be useful? Any "gotchas"?

Any help will be greatly appreciated.

------------------
Raydar
88 4.9 Formula IMSA Fasback..........................88 3.4 coupe................................................

Read Nealz Nuze! Praise the Lowered!

Take a good look at it once apart those plastic intakes were known to crack, plus I am not sure but I don't think the throttle body used a gasket on the N/A engines, the intake side has those nice and crappy rubber tracks to seal. Dan

Alot of cars will run coolant through the throttle body to warm it up, im not familiar with 3800 though.

There is a water passage in the TB. Check there

------------------

" DRIVE IT LIKE YOU LOVE IT"

Thanks, all!

quote Originally posted by ohio86se: There is a water passage in the TB. Check there

Are there any special tricks or hidden perils to removing the throttle body?

Unplug everything, remove a few bolts, and off it comes?

I (and he) know absolutely nothing about this engine.

[This message has been edited by Raydar (edited 10-29-2006).]

Thats it.
just be carefull not to get antifreeze on the MAF wires inside the TB.
OH yea....you might want to unhook the throttle linkage and the cruise if you have it.

quote Originally posted by Raydar: Thanks, all! Are there any special tricks or hidden perils to removing the throttle body? Unplug everything, remove a few bolts, and off it comes? I (and he) know absolutely nothing about this engine.

------------------

" DRIVE IT LIKE YOU LOVE IT"

GM has a service bulletin out about this problem. It seems as though the plastic upper plenums used on the 3800 n/a engines had a problem with cracking around the EGR passage. The coolant passages that lead to the throttle body go right by this EGR passage. It is likely you have a cracked or distorted (melted) upper plenum issue that is the cause of the leak. If this is the case, replacing the gasket won't help. GM sells redesigned upper plenums to fix this problem but they are expensive. I believe NAPA also sells a revised upper plenum but at a cheaper price.

-ryan

------------------
power corrupts. absolute power corrupts absolutely.

Custom Computer Tuning | Engine Conversions | Turbocharging | www.gmtuners.com

Great info, guys!

One more question...
Do you know if the upper plenums that are all over ebay are any good?

[This message has been edited by Raydar (edited 10-29-2006).]

quote Originally posted by Darth Fiero: GM has a service bulletin out about this problem. It seems as though the plastic upper plenums used on the 3800 n/a engines had a problem with cracking around the EGR passage. The coolant passages that lead to the throttle body go right by this EGR passage. It is likely you have a cracked or distorted (melted) upper plenum issue that is the cause of the leak. If this is the case, replacing the gasket won't help. GM sells redesigned upper plenums to fix this problem but they are expensive. I believe NAPA also sells a revised upper plenum but at a cheaper price. -ryan

x2, happend to most of the bonnevilles I work on for some reason..... No cheap "proper" fix, I just junkyard them as they are fairly easy to find/buy/replace as needed.