New rebuild, I may soon have problems!

[Andrew]

I think I have the carbs working about as best I can at this point but I found a possible problem.

I torqued the head down 45lbs when I did the rebuild. I then took her out a few times to work and then re-torqued the head again to 45lbs. I have now taken her to work a few times, one car show and she sure has more power.

Today I messed with the carbs and during this work I could see a little coolant up on the front corner of the head to block .

Should I torque the head down again? I don't seem to be burning coolant but I guess the only way to check is to pull the plugs. What should I be looking for or am I just looking for trouble?

I could use a little help here as this was my first rebuild.

Regards,
Andrew

 

[jumpinjan]

Show a picture of it
Jan

 

[Alpine Addict]

I would guess that this is coming from the thermostat housing at the front of the cylinder head? This would be easy to fix.

 

[65beam]

problem

you could try GM's solution for the last ???? many years . they had a similar problem on their 4 cyl and the warranty repair was stop leak .they did this to my chevy when it had 10000 miles on it ( 1991 ) and i finally gave it away last week with 284000 miles showing .

 

[Andrew]

here is a picture

Show a picture of it
Jan

Hi Jan,

You can see the a little sitting on top of the block in the centre of the photo.
There is not a great deal but it is a worry.
Please tell me what you think.

Regards,
Andrew

 

[serIIalpine]

I would recommend going to an autozone and getting a cooling system pressure tester and pumping it up to 10 lbs and seeing where the leak is.

Thermostat housings (cracks) and gaskets are notorious leakers.

Read the label on the stop leak and you'll never put it in your car.


Eric

'62 SerII

 

[puff4]

I agree that Stop Leak is over-used, but I'm not sure you can write it off entirely. Similar to 65Beam, my Chrysler had a very tiny weeping from the head gasket and I used Stop Leak... that was at about 40K and the car now has 110K with no issues... and no leaks.

Stop Leak is only effective, I think, on systems that are in basically good shape, but that may have a tiny weeping leak that would be very expensive to fix in any other way.

I agree with Eric, though, that you should pressure test the system to find the leak before you do any service or add anything to the coolant. This looks like too big a leak for Stop Leak.

 

[Andrew]

It is not a big leak, I just see a little puddle there after I stop the car, no spray or anything around the car. The coolant has not gone down at all as I see it. I have installed a new rad, cap and overflow. I checked things and she is topped right up. Mind you with the overflow, I do have extra collant that can be used in the system.

I will see if I can get it pressure tested this week. She has all new gaskets and I can't see the need to put stop-leak in the rad.

Any other ideas I sure would love to hear them.

Regards,
Andrew

 

[alpine_64]

Andrew,

What kind of head gasket did you use? copper or composite?
Did you slightly texture the surface of the block before installing?
Did you use an additonal sealant on the gasket to mouting face?
Did you torque the head in sequence as per the manual?

It looks unlikely this is coming from a source other than the gasket/head gasket/block... so im thinking you are having issues sealing there not leaking from another joint like thermostat etc...

 

[jumpinjan]

Andrew,
I would think its coming from the thermostat housing. On one engine rebuild, I noticed a similar thing. It was a crack in the housing that was very hard to see. It was almost imposable to see.
That cast aluminum housing is pretty delicate. Check the flatness of the faces too, they could be bent and damage from screwdrivers prying the housing off.
Jan

 

[Andrew]

Andrew,

What kind of head gasket did you use? copper or composite?
Did you slightly texture the surface of the block before installing?
Did you use an additonal sealant on the gasket to mouting face?
Did you torque the head in sequence as per the manual?

It looks unlikely this is coming from a source other than the gasket/head gasket/block... so im thinking you are having issues sealing there not leaking from another joint like thermostat etc...

1) Composite Gasket
2) I had no idea about texture needing to be on the surface??
3) Copper spray sealant was used on gasket mounting face.
4) I did the torque as required in the manual and as per Jim (the dark side )

I will check the water pump and therm/housing.
Thanks for the help.

P.S. I would love a little more information about the texture needed on the head?

Andrew

 

[SIVAllan]

Andrew,

I had a similar leak that turned out to be due to a poor seal for the front thermostat housing.


Allan

 

[John W]

My V looks exactly like that since I've owned it. Water system seems to stay pressurized without much loss, but I've always had antifreeze in that exact same spot after a long drive.

 

[alpine_64]

P.S. I would love a little more information about the texture needed on the head?

Andrew

i think its the block surface no the head.. but if you have decked the block.. sometyimes the surface has no texture for the gasket to bite into. People (i think jan might have even written about this in the marque?) will pumice the surface to keep a level but slight textured surface to get the gasket some traction. Now.. if you didnt deck the block in your rebuild, did you ensure it was level?

 

[Andrew]

i think its the block surface no the head.. but if you have decked the block.. sometyimes the surface has no texture for the gasket to bite into. People (i think jan might have even written about this in the marque?) will pumice the surface to keep a level but slight textured surface to get the gasket some traction. Now.. if you didnt deck the block in your rebuild, did you ensure it was level?

I am not sure what I would do it I didn't have this club. I checked the head and block when I did the rebuild and things looked good at the time. I am sure that the surface of the head and block are quite smooth and this may be my problem, I didn't surface anything.

Should I just keep an eye on things or would it be wise to pull things off and redo the head/block surface and install a new set of gaskets?

I will check everything first but I will do the work if it is needed. Hey, how is one to learn without doing the work?

Thanks again,
Andrew

 

[Tom H]

Andrew, Before you pull the head be sure it is not the thermostat housing. First try to see if you can spot the leak around that area. Clean and dry everything around the area completely with paper towels and tissues. Then run the motor up to temp and see if you can see the leak. It's probably such a thin flow that you may not see anything. Use a tissue to touch all the surfaces, bolts, and cracks ABOVE the head/block separation line. If any coolant shows up on the tissue then you know the leak is NOT the head gasket, because coolant cannot flow UP. If the leak is at the bottom edge of the housing it may be very difficult to see even with this method, but maybe you can put some tissue on a screwdriver tip and reach into that area.

You might also try by just tightening the thermostat housing bolts.

I'd say that it's a 10:1 odds that the problem is in the thermostat housing.

Tom

 

[Paul A]

Andrew, Before you pull the head be sure it is not the thermostat housing. First try to see if you can spot the leak around that area. Clean and dry everything around the area completely with paper towels and tissues. Then run the motor up to temp and see if you can see the leak. It's probably such a thin flow that you may not see anything. Use a tissue to touch all the surfaces, bolts, and cracks ABOVE the head/block separation line. If any coolant shows up on the tissue then you know the leak is NOT the head gasket, because coolant cannot flow UP. If the leak is at the bottom edge of the housing it may be very difficult to see even with this method, but maybe you can put some tissue on a screwdriver tip and reach into that area.

You might also try by just tightening the thermostat housing bolts.

I'd say that it's a 10:1 odds that the problem is in the thermostat housing.

Tom

Andrew: I concur with Tom's diagnosis. A leak around the thermostat housing is fairly common, it seems. They seem to warp a bit and lose "flatness". If you remove the housing you can easily check it with a straight edge - I use a carpenters square - the small, hand held type. If it is not perfectly flat you can surface it in a number of different ways.

I do not use paper or composition gaskets for installation. I use Permatex as it will readily accomodate any imperfections on the housing.

 

[Ken Ellis]

Has anyone here made such gaskets from silicone rubber sheets? (Sold as hot pads or baking ware...) I've seen some pretty thin ones, and they are supposed to be good up to 500 degrees or so. (Paper is only good to 451 degrees?) On a low-pressure system, it seems they would work.

Ken

 

[Nickodell]

Hi Andrew. I had what appeared to be a leak from the thermostat housing joint with the head. When I took it off to replace the gasket, it literally fell apart. 35 years of having hot coolant zipping through had eroded the metal until it was less than 1/16" thick in places and had actually opened up to a pinhole on the underside, which was where the coolant leak was.

In regard to leak stops, I used Bar's Leaks on Matilda when she developed a tiny leak from the radiator, and it lasted over 20 years. The military use this stuff.

Does anyone remember the (Prestone?) antifreeze with its own leak stopper included; remember, with the TV commercials showing the guy punching holes in a can, and the leaks stopping? Is this stuff still sold?

 

[RootesRacer]

In regard to leak stops, I used Bar's Leaks on Matilda when she developed a tiny leak from the radiator, and it lasted over 20 years. The military use this stuff.

Does anyone remember the (Prestone?) antifreeze with its own leak stopper included; remember, with the TV commercials showing the guy punching holes in a can, and the leaks stopping? Is this stuff still sold?

Ive always been wary of stop leak and the like.

Though I have no first hand experience with it (since I was too wary to try it), it would seem to me that anything that could stop a pinhole leak would also stick to everything it touches in the cooling system (IE the cooling tubes and block), the thermal conductivity of the cooling system and thus the cooling efficiency would be compromised.

Anyone have contradictory data or opinions?