Moparts

where is the coolant coming from? 426 Hemi "UPDATE"

Posted By: maxie

where is the coolant coming from? 426 Hemi "UPDATE" - 08/29/13 05:07 PM

The last couple of days I have been seeing coolant on top of the oil pump. I dont remember if the hemi is like a wedge and header bolts go into the coolant. I am finding the coolant on the inner piece of the housing where the outer piece of the housing goes up against it. There is a low area there. We are talking about less than a thimble off coolant a day. Motor has less than 20 miles on it and is all new parts.
Posted By: mbogina

Re: where is the coolant coming from? 426 Hemi - 08/29/13 05:38 PM

IIRC, the front header bolts on No. 1 cylinder go into the Head bolt hole, the rear 2 are blind but if they are drilled too deep they could break into water, if so, a bit of silicone will fix it. Also possible that you are leaking at the top front corner of head and the coolant is running down front edge of head onto oil pump.
Posted By: B G Racing

Re: where is the coolant coming from? 426 Hemi - 08/29/13 06:28 PM

Hemis have a habit of leaking at the front and back of the heads at the large coolant passages(see outward bump in head casting),pressurize the system amd check these areas for coolant leaks.
Posted By: HemiDart68

Re: where is the coolant coming from? 426 Hemi - 08/29/13 06:53 PM

Quote:

Hemis have a habit of leaking at the front and back of the heads at the large coolant passages(see outward bump in head casting),pressurize the system amd check these areas for coolant leaks.



Yep. Sometimes if it just a suttle leak radiator pellets will fix it. Go to a GM dealer and buy them, they work really well.
Posted By: B G Racing

Re: where is the coolant coming from? 426 Hemi - 08/29/13 08:38 PM

Quote:

Quote:

Hemis have a habit of leaking at the front and back of the heads at the large coolant passages(see outward bump in head casting),pressurize the system amd check these areas for coolant leaks.



Yep. Sometimes if it just a suttle leak radiator pellets will fix it. Go to a GM dealer and buy them, they work really well.



Always check the head gaskets in this area since the block and heads coolant holes vary from manufacture to manufacture.We usually put silicone around these areas for extra insurance.
Posted By: rickseeman

Re: where is the coolant coming from? 426 Hemi - 08/29/13 09:05 PM

I have had that happen when I put the head gaskets on dry per the manufacturers specs. So then I had to take the heads back off and spray copper coat on them like I wanted to do in the first place and then they didn't leak. As said above, the exhaust bolts and the head bolts are dry on a hemi.
Posted By: dogdays

Re: where is the coolant coming from? 426 Hemi - 08/29/13 09:14 PM

Pellets you can find in the plastic bottles of Bars Leaks at your local WalMart. Not the absolutely cheapest version, the next step up in price. The bottle is clear in some areas, be sure to shake it up so all the little pellets roll out into the radiator.

For the head gasket water leaks I would suggest that blue Rolls-Royce stuff (forgot the name but it is better than silicone for this application.)

R.
Posted By: MR_P_BODY

Re: where is the coolant coming from? 426 Hemi - 08/29/13 10:12 PM

I add a bottle of Bars Leak to every build I do..
I silicone the head and exhaust studs also, just in
case they are drilled deep... then the bottle of stop
leak is just insurance
Posted By: Oyvind Mopar

Re: where is the coolant coming from? 426 Hemi - 08/29/13 10:25 PM

Quote:

Pellets you can find in the plastic bottles of Bars Leaks at your local WalMart. Not the absolutely cheapest version, the next step up in price. The bottle is clear in some areas, be sure to shake it up so all the little pellets roll out into the radiator.

For the head gasket water leaks I would suggest that blue Rolls-Royce stuff (forgot the name but it is better than silicone for this application.)

R.

Blue Hylomar!
Posted By: MrSixpack

Re: where is the coolant coming from? 426 Hemi - 08/30/13 08:27 AM

Quote:

I add a bottle of Bars Leak to every build I do..
I silicone the head and exhaust studs also, just in
case they are drilled deep... then the bottle of stop
leak is just insurance




Same here, bars leak in every build I do and no problems ever.
Posted By: dogdays

Re: where is the coolant coming from? 426 Hemi - 08/30/13 06:12 PM

Thanks, you son of Odin!

Hylomar is neat stuff and everyone should have a tube or two lying around to seal up those nasty areas.

R.
Posted By: maxie

Re: where is the coolant coming from? 426 Hemi - 09/01/13 08:27 PM

After I posted this I went out and looked at the area where the head bolts on.

I wiped down the head and front of the block real good with a rag and have not seen anymore coolant on the oil pump.
I had changed the thermostat a few days earlier and didnt know if the fan sucked coolant all over the motor that I may have spilled while filling it up
Posted By: maxie

Re: where is the coolant coming from? 426 Hemi - 09/01/13 08:29 PM

Also when I was wiping it off a little paint came off the bottom of the head, where it over hangs from the deck. I thought maybe water had leaked and was trapped in there when we fired it up for the first time.

Have not started the car since I have wiped it all down., may only leak after running
Posted By: Mopar Grandpa

Re: where is the coolant coming from? 426 Hemi - 09/03/13 06:27 PM

You should have bought my HEMI car......it never leaked water. Now oil is another topic.
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