99 ga 3.4 leaking coolant out the block.
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From: hobart indiana (1 hr from chicago)




hey guys. so a few weeks ago a friend of mine said her ga was leaking coolant and a mechanic friend told her it was the headgaskets. so i went on over and we replaced the headgaskets. put coolant in, and its all on the floor. upon further inspection, it seems to be leaking out of what seems to be a bolthole to the left (firewall side) of the harmonic balancer. there is one hole that i can fit almost the entire tip of my index finger into that is full of coolant, but it dont seem to be coming from that hole. looking at my mothers 3.1, the same hole is present, without the massive amount of coolant obviously. the freeze plug on the head is sealed up good.
thanks alot for any ideas guys!
thanks alot for any ideas guys!
i dont know what the hole is but figure since the other one had it too its normal and likely a collection point for the leak instead of the source. some times the leak is easier to see if you pressure test it so you arent fighting the belt/fan and stuff. if it on the floor i dont see what else would leak besides the heater core to put coolant inside. just make sure its not a water leak
Have you looked to see if it is coming from the timing chain cover?
I am pretty sure there are two coolant ports in it that can leak in that area.
The other thing I'd inspect is intake manifold gaskets.
I second Justin'* suggestion to pressure test it and look for the leak then.
I am pretty sure there are two coolant ports in it that can leak in that area.
The other thing I'd inspect is intake manifold gaskets.
I second Justin'* suggestion to pressure test it and look for the leak then.
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From: hobart indiana (1 hr from chicago)




i just contacted her about it. havent talked to her since i posted the last comment. i will post as i get more information. thanks guys
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From: hobart indiana (1 hr from chicago)




OK, just left the girls house and I'm at hooters now
Figured in the 45 mins I been waiting I'd go ahead and post this up. Looks like the timing cover to me, but the only way I could see it that close was looking at the video. So I can see pretty much what y'all can. Any info is appreciated.
Figured in the 45 mins I been waiting I'd go ahead and post this up. Looks like the timing cover to me, but the only way I could see it that close was looking at the video. So I can see pretty much what y'all can. Any info is appreciated.
Looks like that lower left coolant port in the timing cover is leaking, you can get the timing cover gasket kit from rockauto for about 7.00, not sure how hard it is to replace the gasket though, I have never done one myself.
FEL-PRO Part # TCS45976
Type: Timing Cover Set w/Sleeve; w/Sleeve 'N' Seal®; .565" sleeve length; MFI
One thing I noticed, that bolt almost looks like it has backed out a bit, unless it is not supposed be be flush with the surface it is going into, you may want to check torque on it says Timing Belt Cover Bolt – 89lb.in in the gm manual for the 3400, can anybody verify?
Also, I am pretty sure there is a torque sequence, I'll try to find that info unless somebody beats me to it.
FEL-PRO Part # TCS45976
Type: Timing Cover Set w/Sleeve; w/Sleeve 'N' Seal®; .565" sleeve length; MFI
One thing I noticed, that bolt almost looks like it has backed out a bit, unless it is not supposed be be flush with the surface it is going into, you may want to check torque on it says Timing Belt Cover Bolt – 89lb.in in the gm manual for the 3400, can anybody verify?
Also, I am pretty sure there is a torque sequence, I'll try to find that info unless somebody beats me to it.





