Coolant leak how to fix

[formula46two]

Well I topped off the engine with coolant and of course there's a leak. I'm sure it's from letting it sit for so long but I have to take a step back to remedy. I believe it's coming from the rubber seal between the intake and timing cover so question is what is the correct procedure to get a new seal in? Do I leave the timing cover in place and remove the intake or vice versa? Man I didn't need this but gotta deal, right.

[b_hill_86]

First thing I would try is loosen the intake bolts then snug the bolt that draws the intake toward the timing cover. Then properly torque the intake bolts. Can’t hurt to try. If you try that and it doesn’t work or skip it, I’d remove the intake, replace the o-ring and reinstall following the same procedure of drawing the intake forward first then tighten the intake bolts.

[formula46two]

First thing I would try is loosen the intake bolts then snug the bolt that draws the intake toward the timing cover. Then properly torque the intake bolts. Can’t hurt to try. If you try that and it doesn’t work or skip it, I’d remove the intake, replace the o-ring and reinstall following the same procedure of drawing the intake forward first then tighten the intake bolts.

Thanks, I'll try that. Now I know why some separate the coolant intake and the intake

[b_hill_86]

You’ll want to replace the intake gaskets too of course and a little RTV can help with the o ring too

[5th T/A]

Years ago I installed many Pontiac intakes without leaking problems pretty much the same as Brian mentioned, having the intake to head bolts started, then draw the intake forward with the single water pump bolt. I might have used some Permatex aviation formagasket on the O-ring doughnut. I read somewhere there were problems with some of the new doughnuts not being thick enough. Not confirmed.

I also like to use a cooling system pressure tester on the system putting about 15 PSI while checking for leaks. This allows leak testing without topping off the cooling system or running the engine. I bought mine forty years ago. Most auto parts stores will lend one for free.

[nUcLeArEnVoY]

Probably the most notorious coolant leak point on a Pontiac motor.

As others have said, you only bolt down the intake not even finger tight; and you tighten the draw bolt first to effectively "pull" the intake into the timing cover to compress the donut seal. The spec is 15 lb-ft, but it goes more by feel since that draw bolt is prone to snapping easily. Once that's torqued, THEN you torque the intake bolts to spec.

A bead of RTV along the machined flange on either the intake or timing cover is permissible for a little extra insurance. Shouldn't have to put any on the donut itself.

[formula46two]

Thanks I will tackle this Sunday..

[tinpusher]

Did you get it fixed? I just noticed  a small coolant leak collecting on the front of the my valley pan… mine was dripping from the back side of my thermostat housing and slowly making it down.
It seems like I have had three different thermostat housings that have had issues…. All aftermarket.

[Zach]

Did you get it fixed? I just noticed  a small coolant leak collecting on the front of the my valley pan… mine was dripping from the back side of my thermostat housing and slowly making it down.
It seems like I have had three different thermostat housings that have had issues…. All aftermarket.

I have a chrome one that used to leak a lot, people suggest using only RTV and it seemed to fix, never had luck with a gasket. Going on a year or so since the repair and it’s dry.

[nUcLeArEnVoY]

^^^ Yeah, I'm usually the one who recommends using straight RTV. And the only reason I recommend it is because it also happens to be what the factory service manual recommends when re-installing the thermostat housing. I tried two different types of paper gaskets and both of them end up wicking coolant and eventually springing a leak.

A 1/8" bead should do just fine, and the one I recommend is Permatex Waterpump and Thermostat Housing RTV.

[b_hill_86]

I use a chrome neck with an o-ring. No leaks and I’ve had it off at least twice that I can think of and it resealed each time. First time I’ve not had any leaks out of a neck. Don’t ask me what brand or where I got it though, I don’t remember lol