grandprix00

Hi i have a 98 blazer 4.3 when i start it there antifreeze leaking from the bottom u can see from the front and the back and its rly bad leak frist thought maybe freeze plug and idea where to look for because u rly cant see if the back freeze plug is bad b.c its in the bell housing isnt it and heard to check under the starter im just looking for ideas

the upper intake gasket is leaking i can see on the top but would it cause it to leak that much and even when i had the car off and i put more water in the radiator it still leaks pretty good under the car thats what i thought it would be a freeze plug.

tempfixit

Sounds like the intake manifold gasket needs to be replaced, Check into a Fel Pro set. I would rent a pressure tester from autozone and see if you can pinpoint the leak first.

grandprix00

cant see it rly its in the back area too front leak looks like its comming from the lower intake and draining down to the bottom and yah there isnt too much room in the back to see where thats comming from im going to try a lower intake gasket kit first i think its only $65 for a gasket kit anyways

ZL1power69

The upper intake gasket will not leak anything except air. The lower intake gaskets failing is a very common issue with these trucks but it is not covered under the GM Dexcool lawsuit. Check to make sure all of your intake bolts are tight (don't forget the one under the ac compressor bracket). Then get a pressure tester and see if the manifold still leaks. If it does, fix it immediately to avoid further engine damage. Definatly use the felpro gasket set, they are very high quality. Flush the cooling system and heater core multiple times to remove any sludge. I would also recomend converting to std green antifreeze to avoid any other dexcool related problems.

__________________
2000 Chevy Blazer ZR2
Performance: AEM intake, TB mod, ported stock y-pipe w/precat deleted, 3in catco cat, 2.5in Flowmaster 40 DF,
March pulleys, MSD SF ignition, Taylor 8.2 wires, Transgo shift kit, Corvette servos, B&M trans cooler.
Suspension: Knaffle 1.5in lift shackles, 1.25in rear wheel spacers, 31in BFG AT's
Exterior: custom ZR2 decals, bug guard, vent visors
Interior: Lanzar headunit w/ ipod input, Pioneer speakers, Scanguage II

http://www.cardomain.com/ride/3013891

MT-2500

Also watch/check engine oil for coolant in it.
And change oil and filter after intake replacement.

__________________
Remember proper testing gives us the answer to many problems.
MT

skyzend

Ok, So here is a thread I have some experience with.
Lower intake manifold at the back. Mine was great until the 230Km mark.
I've had leaks there, block heater which is escentially a frost plug like filler.
Both leaked under a preasure test ...

Couple of things. If the Lower intake gasket is going and leaks that bad, there is a good chance of coolant inside the engine. This is a huge problem that needs to be dealt with quickly and effectively. Not addressing this right away will likely lead to main bearing failure on a car of this age an presumably a lot of milleage.

Mine did not have any coolant in the oil, but the dealer screwed the repair and spun the bearings while performing the afterrepair tests. In other words. getting the repair correct is tricky. You must be carefull that the gasket seal is good ... an aditional preasure test is adviseable. there is little room here for error.

Secondly, if you have a leak then you will not have the desired preasure in the coolant (Presuming Dexcool orange coolant). Without this peasure the coolant boiling point will be too low and the coolant will start to boil off at normal running temp. this will lead to sludge buildup that has a habit of gumming up the car heater core.... more problems. If you hear a gurgling sound from the heater core area after the car is turned off.... this is likely the cause.

Bottom line .... need to get this fixed fast. You just can't keep topping the coolant reservoir.

By the way, the dealer replaced my engine with a comparable replacement at his cost. (Mine had 230K, replacement had 205K, Now we are at 335K with no further issues so far ... We both checked the oil when I took it in and that was prominantly noted on the initial analysis of the problem. Without this I would ahave had to burden the whole cost ... a word to the wiser ... put things in writing even the obvious.

rasmith527

My 98' did the same. My trouble was a lower intake leak which caused antifreeze to drip from the rear of the engine onto the exhust which began buring off when it was hot. Have it checked by an engine professional or dealer. My total repair cost was $3300 because I had some additional maintenance work done (tune-up, fuel line cleaning, intake cleaning, etc.).