Hello I have a 98 blazer LT 4x4 4.3L. Anyways about a month ago I replaced the intake gaskets because of the notorious coolant leak. Things went well and the engine runs great and still does. However the other night while it was idling I noticed the sweet smell of antifreeze. I popped the hood to check and sure enoughcoolant is seeping out were the gaskets are.[:@]Not a bad seep, just a little one. It seems the cold snap we had in the last week may have contributed tothis.

While performing the job I made sure all surfaces were very clean and oil free, used sealant on the coolant passage surfaces (only on the manifold side), torqued everything to manufactures specifications and in sequence. The gaskets used had steel washers embedded around the bolt holes to prevent over compression. Which shouldn’t be a problem anyways since I torqued them to spec.
I suspect that the manifold is warped. Is this a common problem and should the gasket surfacebe groundby a machine shop? Or is this practice not recommended.Should I look into other options like purchasing a different manifold? In the mean time would it be okay to snug up the front bolts were its leaking to maybe subside to leak a bit? Any help would be appreciatedbecauseI go to school fulltime andI’m hopingthings holdtogether until summer when I have more time. I’m keeping a close eye on coolant levels as well as possible coolant getting in the oil.

 

What do you mean (used sealant on the coolant passage surfaces (only on the manifold side),, did you glue the gaskets to the intake manifold?

I put a little sealer on the cylinder heads (actually I use weatherstrip adhesive), then put the gaskets on to the heads, then put a bead of silicone sealer on the front and rear sections of the engine (to about 1/4" up the edge of the gasket). Then I apply pipe thread sealant to about 5 threads of the manifold bolts before I re install them..

Maybe you could re-torque your bolts, I usually check mine 3 times

 

Well I guess you could say I "Glued" The gasket to the manifold. So many people have told me that you need to apply sealant around the coolant passages. I always thought that you install silicon bead gaskets without any sealer. I guess I learned my lesson here [&o]. However Ill check the bolts and see if that helps.

 

Yeah I'd say sealer is your problem. These gaskets go on clean and DRY. You DO NOT put ANY sealer or glue etc. on the gasket surfaces. Like chevylover said put some pipe sealer on the first few threads of the 8 bolts that hold the lower manifold on and a kind-of thick bead of sealer on the front and rear section of the block that mates to the intake manifold (seals in oil not coolant). As for warpage, I've never seen one of these manifolds warp, but when you get it off throw a straight edge on it just to be sure. Also make sure the bolts are tightened in sequence AND to spec.

 

Thanks guys for your input. Guess when I get a free weekend Ill battle the beast...again.Now its time to pick up a new gasket set! Ill be buying Felpros updated version vrs the victors I put on before. Hope everything goes well. At least things shouldgo more smoothlysince ive done it once before!

 

While that bottom manifold is off, I'd have a machine shop check it for warping. Will only cost a few bucks and well worth it.

Read the shop manual carefully and use ONLY the sealers recommended, and only WHERE recommended. More is NOT always better.

Also, make sure to do the correct 3-step torque procedure using the tightening pattern shown in the manual.