skymark

Thanks to everyone for your thoughts. I'm confident that we installed the seal correctly, so I've been leaning toward going to the old rope seal. Even if I leave a couple of drops here an there, I can drive the car, which I can not do now. I stumbled onto BOP Engineering that offers a rear main seal that is supposed to be specifically designed for the Buick big blocks, as opposed to the retrofit that TA and others are selling (it has FORD stamped on it). I was wondering if anyone has any experience with BOP. The seal is $35 or $40, but if it doesn't leak and allows me to keep my engine where it's supposed to live, then that is a small price to pay. Thanks again and Happy New Year. Mark

Thanks Roadhog. When we removed the first seal, the edge of the seal looked uneven all the way around, which is why I looked for burrs or imperfections on the crank, but it was almost as if it was, like you said, chewed. I will do my best to pinpoint the exact location of the leak before I start taking anything apart, but I don't have a ton of experience to fall back on, so if anyone can help with suggestions of other things to look for I sure would appreciate it. P.S. I took your advice and added my location to my profile...Thanks

Thanks guys very much for your input. When the first one leaked, we were really careful with the second one. I guess I'll have a better idea once we pull the motor and get the seal out, but I'm really hesitant to just replace this seal again unless we actually find something wrong. This motor project has been an 18 month marathon. Now I'm finally this close, the motor runs fantastic, and I can't get past what I think should be a minor issue. If anyone has suggestions as to problems of this nature that they may have seen in the past, I sure would appreciate their sharing. The surfaces of both the block and the crank have been gone over thoroughly (although I'm sure we will do so again when we get this seal out), no burrs or imperfections were found. Thanks again for your responses, and I sure would appreciate any suggestions on other things to look for. I dread pulling this motor again, and want to make this the last time for a while if at all possible. Mark

Hello, I'm new to your site and was wondering if some kind soul could give me some good advice. I have a 1972 Skylark Custom Convertible. I picked up a 1973 455 and did a complete rebuild. I bought one of the TA Performance "NO Trim" rear main seals. Within 5 minutes of starting the new motor, the rear main was gushing. We assumed that something just got screwed up in the assembly process, so I bought another "NO Trim" seal from TA, we checked the crank and all the area around the seal for burrs, etc., installed the new seal and put the motor back in. Twenty minutes after startup, the rear main is gushing again. I'm wondering first if others have had problems with these seals, or if maybe there is some trick that we are missing in getting it to actually seal? My second question is if there have been problems with these seals, is there an alternative other than the old style rope type seal, or is that my best bet? I certainly don't want to have to pull this motor a 3rd time. Thanks very much for any advice that can be provided. Mark