Re-sleeved LS1 Block problems
The block may also be cracked. You can not put much press into these blocks because of the non ductile aluminum alloy used.
I would recommend trying the Moroso ceramic engine sealant. I have successfully sealed problem Honda blocks using this product.
Carefully follow the directions. I use the stuff on bare blocks, not with a complete running engine in the car. You do not want to plug up your radiator and heater core.
Steve
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
You need to find where the leak is first. Pressurize the block with 25 psi of air. Spray the areas around the sleeves in the crankcase with a soap water mix or something like Windexor Fantastic to find the leak or leaks.
Assuming you find the leak, release the air, mix up the Moroso Ceramic engine sealer with hot water, enough of if to fill at least half the water jacket area on the bank you will seal up first. Remove the front block off plate on the side you are sealing, pour in the mixture, replace the plate and pressurize with 25 to 35 psi of air. Orient the block so you are certain the mixture covers the area that is leaking. It should seal up up the leak in a couple of minutes or less, that is if it is sealable. If you are successful, pour the solution out and do the other bank if it is also leaking, again with hot solution.
We are assuming the block is the culprit and not the heads. If you can not find a leak pressure check both heads.
Steve
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net




