[grivera]

I've had the bird in hibernation for over a month. I looked at the "catch-pan" underneath and there is antifreeze on it (a pretty good amount). I never had any overheating issues and the antifreeze is very clean. This is a fresh build and the location of the puddle is the p-side toward the back of the engine. I have to move various items to jack the car up- any idea what could be leaking? Will a head gasket do this?

[DOC]

I would check the heater hose on top of the passenger rear head and the heater core first

[grivera]

Thanks, I'll check that. I failed to mention that I bypassed the heater core, the hose run from the water pump, into the head. I certainly hope it isn't the freeze plug on the back of the p-side head.

[chuckies76ta]

Sounds like the freeze plug at the back of the head.. Hate to say that, but that's what I had on one head.

I cute out a piece of metal filled the freeze plug area with The Right Stuff and installed the metal cap over the plug.. till the day I pull the engine and fix it properly.

There are bolt holes on each side of the freeze plug that I used to secure my metal plate..

Had my son make me a 3/16" steel plate with the holes drilled so it secured to the head..

No more leaky..

Charles

[grivera]

Originally Posted by chuckies76ta

Sounds like the freeze plug at the back of the head.. Hate to say that, but that's what I had on one head.

I cute out a piece of metal filled the freeze plug area with The Right Stuff and installed the metal cap over the plug.. till the day I pull the engine and fix it properly.

There are bolt holes on each side of the freeze plug that I used to secure my metal plate..

Had my son make me a 3/16" steel plate with the holes drilled so it secured to the head..

No more leaky..

Charles

I'll have to examine that area closely. This is really frustrating since I have no plans to pull the head. You're temporary solution is intersting for sure...

[Pontirag]

how you eliminate that is by replacing them at rebuild time. its senseless to save 8 bucks on a rebuild by forgoing freeze plug replacement. you can never tell a thing about freeze plug condition from looking at the outside of them. However you can be certain simply by replacing them. it at least eliminates the freez plugs from the troubleshooting/fear variables list

[69Customs]

I throw in a can of coolant stop leak sealer in every rebuild. I've heard gm put a can of stop leak in each new engine as insurance, don't know if thats true.

[PunchT37]

Check the torque on the intake and the head bolts if you don`t find a leaking freeze plug or hose. The cold weather can do tricks on metal expansion. A lot of cold engines will leak, but stop when warm as the components warm and expand.

[grivera]

Originally Posted by Pontirag

how you eliminate that is by replacing them at rebuild time. its senseless to save 8 bucks on a rebuild by forgoing freeze plug replacement. you can never tell a thing about freeze plug condition from looking at the outside of them. However you can be certain simply by replacing them. it at least eliminates the freez plugs from the troubleshooting/fear variables list

Where did you get the impression that the freeze plugs weren't replacced? All of the machine work on my block and heads was performed by a machine shop and they installed new brass freeze plugs throughout. Apparantly mere replacement isn't a guarantee that they won't leak.

[Kyflier]

You might check the rear head bolt as well. If you didn't use a sealer on it, might be seeping.

[grivera]

Originally Posted by Kyflier

You might check the rear head bolt as well. If you didn't use a sealer on it, might be seeping.

I didn't use sealer on any head bolts, I didn't know I had to. Which head bolt are you referring to and will this apply to both heads?

[grivera]

Originally Posted by 69Customs

I throw in a can of coolant stop leak sealer in every rebuild. I've heard gm put a can of stop leak in each new engine as insurance, don't know if thats true.

This build has less than 300 miles on it, will it still work if it ends up being a freeze plug. Does stop leak have any negative effects on the radiator (aluminum)?

[Murf'sDad]

Originally Posted by Kyflier

You might check the rear head bolt as well. If you didn't use a sealer on it, might be seeping.

Pontiacs don't need sealer on the head bolts. That's a Chebby trick.

Stewart

[chuckies76ta]

Originally Posted by grivera

I'll have to examine that area closely. This is really frustrating since I have no plans to pull the head. You're temporary solution is intersting for sure...

I'm wondering if the 62 heads have the same head bolt arrangement like my 197 heads?

I wouldn't remove the head just to repair the frost plug. The coolant stop leak might work also as was mentioned.. I'm not a fan of the product..

I can draw you a pic of what I did if your interested..

If you do happen to remove the head to change the plug, make dam sure there are no pits or damage to the frost plug hole. I used a bit of JB weld to smooth out the frost plug hole.

When installing the new frost plug make sure to coat plug and hole with Loctite gasket sealant.

Charles

[chuckies76ta]

Ya no sealer on head bolts.. All block holes are blind..

Charles

[grivera]

Originally Posted by chuckies76ta

I'm wondering if the 62 heads have the same head bolt arrangement like my 197 heads?

I wouldn't remove the head just to repair the frost plug. The coolant stop leak might work also as was mentioned.. I'm not a fan of the product..

I can draw you a pic of what I did if your interested..

If you do happen to remove the head to change the plug, make dam sure there are no pits or damage to the frost plug hole. I used a bit of JB weld to smooth out the frost plug hole.

When installing the new frost plug make sure to coat plug and hole with Loctite gasket sealant.

Charles

Thanks. I am interested in your drawing.

[69Customs]

If a machine shop built and assembled engine I would go back and ask them what they recommend, If a machine shop did the work and you assemblied I would try a can of stop leak. If that doesn't work use radiator pump pressurizer test tool to find where its leaking. Then go from there.
Stop leak will not harm alum radiator if used spearingly. I use it as an insurance program cause I don't do enough freeze plugs to be super good at it, and don't trust myself completely. Had to remove and replace a few of my freeze plugs.

[grivera]

Originally Posted by 69Customs

If a machine shop built and assembled engine I would go back and ask them what they recommend, If a machine shop did the work and you assemblied I would try a can of stop leak. If that doesn't work use radiator pump pressurizer test tool to find where its leaking. Then go from there.
Stop leak will not harm alum radiator if used spearingly. I use it as an insurance program cause I don't do enough freeze plugs to be super good at it, and don't trust myself completely. Had to remove and replace a few of my freeze plugs.

I did the assembly, thanks for the advice regarding the pressurizer tool.

[Evil Stu]

Sorry you're having trouble. Before using stop leak or such, find the leak.

Reading the thread I'm not sure that you've determined that it is the plug. If you still have not made sure it is the plug remember that fluid, especially coolant, can travel a long way along components before dropping to the ground. Is there any evidence of coolant on the valley pan under the intake manifold? A leak at the front can run along the top of the engine and drain down the back.

Maybe get a hold of a cooling system test pump, they're cheap. You put it on where your rad cap goes and pump up the system. Having pressure in the system may make it easier to trace the leak.

HTH,

Stu

Edit: Sorry for the repeat, 69CustomS is reading my mind while I'm writing....

[x-bird2]

I've run into this on a fresh build also. take a paper towel and push it down hard where the valley pan meets the head below the intake. start at the front. If it comes up wet, you've found the culprit. chances are it's seeping out between the manifold and head and running along the pan's upper edge to the rear of the engine. sounds like the engine's had a few heat cycles and the manifold needs a bit of tightening. i've seen the both the thermostat elbow/gasket and the water cross over do this. It can also come from the pump connection (improper torquing sequence with the long bolt.) and drip/blow back from the underside below the junction.