crank shaft seals

[GC]

I have a 1961 CC Constellation, the 283's are history so we are changing to 350's. I have Paragon transmissions model HF 2D. My engine builder has advised me the crank seals are not the same as a standard application. Can any one shed some light on this and let me know where these seals can be bought. There is a part number in the CC book from 1961 for these seals but they do not cross up with any modern books. Any help would be appreciated.

[BOBHERAS]

GC, GET A "CR" CATALOGUE AND LOOK FOR A REPLACEMENT SEAL. YOU WILL NEED TO KNOW THE OUTSIDE AND INSIDE DIAMETER AND THICKNESS OF THE EXISTING SEAL, OR MEASURE THE COMPONENTS TO GET THIS INFORMATION. AFTER THAT ALL YOU HAVE TO DO CHOOSE THE SEALING LIP CONFIGURATION THAT SUITS THE APPLICATION. I HAVE DONE THIS VERY OFTEN WHEN THE SEALS WERE MISSING OR DAMAGED BEYOND RECOGNITION. IF CR IS NOT AVAILABLE GO TO YOUR LOCAL BEARING SUPPLIER AND THEY WILL HAVE LOTS OF SEAL CATALOGUES TO CHOOSE FROM.

[Ian Marchuk]

I have doubts as to why the crankshaft seals in this engine would be much different,unless someone has machined the 350 block and bearing cap in the 350. What was used in the 283 blocks is of no significance as you have no intention of using them. Most GM small blocks in my experience had a narrow split seal{upper and lower-identical and interchangable}. I have heard of machining the cap and block for a one piece seal,used in conjunction with a crank , often custom,built to accept a one piece seal.I might be able to give a better opinion if you posted a picture of the flywheel end of the crank, and one of the bearing cap and block clearly showing the seal area.

[Canoeyawl]

One of the "seal" problems on marine engines vs. automotive is the counter rotation engine must have the correct crankshaft to properly seal. The crankshaft has an oil slinger machined into the rear seal surface to force the oil back into the engine. An automotive crank will not work on a left hand rotation engine. The slinger on the 350 is made up of small grooves and they can be machined off and used with a standard seal, but it is a risk.

[Peter Malcolm Jardine]

The seals are different for each engine. left and right. What CY said is right about the cranks.

Any parts supply house can get the marine gasket and seal sets. I got mine through Autoparts extra.