Options to fix 327 cylinder leaking radiator fluid

[Tony Ecock #41688]

I have a 1966 327 300 original drivetrain, but highly customized award winning "show" car. I do not drive it much at all, however when having an oil pan gasket repaired, the mechanic noticed small drops of radiator fluid coming from one of the cylinders that had been re-sleeved when the engine was rebuilt. He said that given how little I drive it, this may not be an issue, but that radiator fluid will eventually break down the oil and ruin the engine if left untreated. He gave me 3 options. . . rebuild the engine again to try and fix the leak (cost and result unknown since he would not do this); remove the original engine and put a crate motor in ($5,000+) or try running a fluid with a ceramic engine sealer product through the engine that has supposedly been used in Nascar to seal small during races. For now we are going to try to find this sealer and give that a try.

Does anyone have any experience in a similar situation and recommendations?

Is anyone familiar with this ceramic sealer product and whether it really works long term?

Thank you very much.

[Tony Ecock #41688]

Web site on ceramic sealers

Found the following web site showing that others had good luck with these ceramic sealers KW etc.

Still would appreciate input if anyone has first hand experience with an old C2 327... and whether they damage the radiator. . .

Thanks Tony

http://http://www.4m.net/showthread.php?t=101851

[Tony Ecock #41688]

Web site on ceramic sealers

Found the following web site showing that others had good luck with these ceramic sealers KW etc.

Still would appreciate input if anyone has first hand experience with an old C2 327... and whether they damage the radiator. . .

Thanks Tony

http://http://www.4m.net/showthread.php?t=101851

[Joe R.]

Re: Web site on ceramic sealers

Tony,

Your options are limited because the first rebuilder probably did not step the sleeve in the block properly. That's why it's running out the bottom of the sleeve. There is a possibility of putting in a thicker sleeve and stepping it properly but odds are not good.

Only option is either change the block or use the sealer. Block sealers are available at your local parts store and have been used sucessfully for years.

With the limited driving you are going to be doing I would not hesitate to fill her up with a block sealer.

Regards,

JR

[Joe R.]

Re: Web site on ceramic sealers

Tony,

Your options are limited because the first rebuilder probably did not step the sleeve in the block properly. That's why it's running out the bottom of the sleeve. There is a possibility of putting in a thicker sleeve and stepping it properly but odds are not good.

Only option is either change the block or use the sealer. Block sealers are available at your local parts store and have been used sucessfully for years.

With the limited driving you are going to be doing I would not hesitate to fill her up with a block sealer.

Regards,

JR

[Len Rayca]

Re: Options to fix 327 cylinder leaking radiator f

Tony: My guess is that when the block was bored for sleeving, that the cylinder wall was reuptured which is the cause of the leak. This can happen when reboring a block and a cylinder wall has a thin spot from the casting process. I don't know how much oversize you went with the rebore, but I agree J ray that the odds of boring for a slightly larger sleeve are in your favor.

[Len Rayca]

Re: Options to fix 327 cylinder leaking radiator f

Tony: My guess is that when the block was bored for sleeving, that the cylinder wall was reuptured which is the cause of the leak. This can happen when reboring a block and a cylinder wall has a thin spot from the casting process. I don't know how much oversize you went with the rebore, but I agree J ray that the odds of boring for a slightly larger sleeve are in your favor.

[Jim T.]

Re: Options to fix 327 cylinder leaking radiator f

Tony my 96 LT4 Corvette's owner manual has a coolant supplement listed to be used when the coolant is changed. The supplement comes in a blister pack of about 6 tablets that are added. If you go to Bars Leak web page you will find the same supplement available. When I changed my 96's coolant I did add the supplement. The supplement is also listed in the my 96's service manual. From what I understand because of the aluminum heads and cast iron block the supplement is used to seal any leaks that may occur. My son was loosing coolant in his 96 Windstar. Could not find any leakage of the coolant. December of 2003 we installed a container of Bar's Leak in the liquid form and he drove it back home, a 280 mile trip, and no loss of coolant. This is something you could try. Check out Bar's Leak web page.

[Jim T.]

Re: Options to fix 327 cylinder leaking radiator f

Tony my 96 LT4 Corvette's owner manual has a coolant supplement listed to be used when the coolant is changed. The supplement comes in a blister pack of about 6 tablets that are added. If you go to Bars Leak web page you will find the same supplement available. When I changed my 96's coolant I did add the supplement. The supplement is also listed in the my 96's service manual. From what I understand because of the aluminum heads and cast iron block the supplement is used to seal any leaks that may occur. My son was loosing coolant in his 96 Windstar. Could not find any leakage of the coolant. December of 2003 we installed a container of Bar's Leak in the liquid form and he drove it back home, a 280 mile trip, and no loss of coolant. This is something you could try. Check out Bar's Leak web page.

[Len Rayca]

Correction to post

Tony:I made a couple errors in my previous post. I meant to say the cylinder wall was ruptured and, also in the last sentence I meant to say the odds of boring for a slightly larger sleeve ARE NOT in your favor. Sorry for the confusion, I should have previewed the message befor posting it. Len

[Len Rayca]

Correction to post

Tony:I made a couple errors in my previous post. I meant to say the cylinder wall was ruptured and, also in the last sentence I meant to say the odds of boring for a slightly larger sleeve ARE NOT in your favor. Sorry for the confusion, I should have previewed the message befor posting it. Len

[Patrick H.]

Re: Options to fix 327 cylinder leaking radiator f

The others have some good advice regarding your motor and the sealer.

My only addition is that you must be getting some heck of a crate motor if you're spending $5000 on it. The 330 horse motor can be found around $2400, the ZZ4 355 horse at around $3800. My guess is that you're thinking $3800 + installation and other costs for the $5000 total.

Good luck with the sealant.

Patrick

[Patrick H.]

Re: Options to fix 327 cylinder leaking radiator f

The others have some good advice regarding your motor and the sealer.

My only addition is that you must be getting some heck of a crate motor if you're spending $5000 on it. The 330 horse motor can be found around $2400, the ZZ4 355 horse at around $3800. My guess is that you're thinking $3800 + installation and other costs for the $5000 total.

Good luck with the sealant.

Patrick

[William V.]

Re: Options to fix 327 cylinder leaking radiator f

Tony

To add to Patrick's suggestion, I would get a short block and reuse your heads and manifolds. This would save you more money and your engine would look the same as it is now.

However, I would try some engine sealer first. I'm going to use it in my 64 300hp because I suspect the person that built the motor, before I bought the car, did not use thread sealer on the head bolts when the engine was rebuilt. I sometimes find tiny drops of coolant on the heads when I pull the valve covers. I thought about removing the head bolts one at a time and use sealer on the threads, but I'm afraid of opening a can of worms by pulling the threads out of the block. This is a 40 year old engine and I do not want to take the chance.

Good luck.

[William V.]

Re: Options to fix 327 cylinder leaking radiator f

Tony

To add to Patrick's suggestion, I would get a short block and reuse your heads and manifolds. This would save you more money and your engine would look the same as it is now.

However, I would try some engine sealer first. I'm going to use it in my 64 300hp because I suspect the person that built the motor, before I bought the car, did not use thread sealer on the head bolts when the engine was rebuilt. I sometimes find tiny drops of coolant on the heads when I pull the valve covers. I thought about removing the head bolts one at a time and use sealer on the threads, but I'm afraid of opening a can of worms by pulling the threads out of the block. This is a 40 year old engine and I do not want to take the chance.

Good luck.