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- - coolant odor in interior (https://www.gmforum.com/1992-1999-91/coolant-odor-interior-202618/)

coolant odor in interior

The interior of my 99 reaks of coolant when the temperature control is on the hot setting. I'm almost positive it's the heater core. Has anyone had any experiences changing one out on a Series II Bonnie? It's not consuming any coolant and there are no drips. Furthermore, I know it's not an exterior problem because I just changed the upper intake and upper and lower gaskets. It's bone dry under the hood and doesn't smell.

Never changed my heater core but it does sound odd that it is doing it after you changed the intake and gaskets?
How did it go? Did you bleed the air out of the system at the screw on the thermostat
housing?

I had the coolant smell before I did all the intake work. I thought that the coolant smell and the intake work would be two in the same. But, it hasn't proven to be that way yet! I think my coolant smell issue all along has been the heater core. I'm wondering what's involved to change it :?:

I have a Chilton's. I was just looking for some "real life" experience. I'll just follow the Chilton's and go at it!

I have found that for minor leaks a half bottle of Bars Leaks added to the radiator
works wonders. It will save you a lot of time and money.
Its factory installed in many cars and I never had any problems with it.
Last winter my SE developed an intake leak below the throttle area.
I changed to a stant cap, added Bars Leaks and its been running without a leak
since.
One day I'll change the whole intake though.

Yep, that BarsLeaks is neat stuff. When it first hit the market, a sales rep stopped by the service station I worked at and gave us a demonstration. He put some hot water in a soda can, added some of the liqiod Bars Leaks, and poked it with a pin. I'd have to say less than 2 or 3 ounces leaked out before it sealed. We kept the can filled for like 6 months, the stuff never gelled up like we figured it would, and the can never leaked, until the noob knocked it over....

Bars Leak makes me really nervous! I've seen how that that stuff gums up heads and it's not a pretty sight. :roll:

Given the inherant intake issues with the 3800, I'll just have the heater core replaced and not introduce any more unnecessary fluids to the already flaky DexCool coolant. I found a trustworthy shop that will replace it for $250. If I had more time, I'd go at it myself. It looks like an involved job based on the Chilton's manual. Some stuff is better left to the shop! :wink:

Quote:

Originally Posted by jr's3800

Quote:

Originally Posted by vital49

Small reccomendation..... Being that you are going to have the upper intake replaced its also a good time to have the lower intake gaskets replaced as well... We have found that the lower intake gaskets tend to degrade to a certain extent which can also cause problems later...

So if your going as far as to replace the upper intake/gaskets, its advisable to replace the lower intake gaskets as well, Replacing these gaskets may also help sole the slight oil leak that the 3800's develop between the heads.... Good Luck..

Read above (and several other posts)!! :D I just finished the upper intake, upper intake gasket, lower intake gaskets, 180 degree stat, stant radiator cap, and complete coolant system flush! I'm good to go now for a while...just need to get the heater core replaced! :wink:

Thats why you start with the minimum 1/2 or 1/3 bottle and it usually will seal a small leak no problem.
It will not harm the heads or gaskets.

just my $.02: dad put some stop leak in the radiator of our old pickup with a 454 and it plugged the radiator. of course, the radiator prolly wasn't free flowing to begin with.