Gen 4 454 timing cover seal help

I am having my Stbd engine rebuilt in a couple of weeks and have just about all the accessories to replace once I get it back but I am unsure about the stamped steel timing cover seal. This is the rev rotation engine so does it take a special seal ? do they have a rev rotation seal ? any buddy know a part number. It's a 1986 gen 4 454ci / 350 model, fresh water cooling.

Gaskets Fel-Pro #
Head 1 17040
intake 17340
exhaust 17440
oil pan 17985 GM #10159519
rear seal (reverse) 17740
valve job set 17240
(valve cover, head, valve seals, distrib., intake man., exh. Man.)
timing cover set 17872 TCS 45060
oil filter adapter seal Crus. #20156
valve cover (cork) VS 30055C

Dave's info should be enough to get you the parts needed.

In the 'old days' the seals had helical grooves and were rotation specific.....by the time the GEN VI was introduced, technology had improved and the current seals will work in either rotation...

Are you having the engine rebuilt by a shop that is very familiar with the differences in a reverse rotation engine. I believe the rear main is special but the front timing cover seal is the same for either rotation (I could be wrong on the front seal). The piston/connecting rod assembly is different as well as the use of timing gears instead of a timing chain. The distributor is the same and rotates in the same direction but the plugs wires are installed in the dist cap in the opposite orientation.

Also the camshaft is different and new ones are hard to locate now.

hottoddie said:

.... The piston/connecting rod assembly is different as well ....

Click to expand...

Same rods and same pistons; pistons are installed 'backwards' to maintain their thrust side in correct orientation....

hottoddie said:

Also the camshaft is different and new ones are hard to locate now.

Click to expand...

Not too hard to find but their cost has gone up a bunch in the past decade....

Thanks guys for all your help ! the shop is a local rebuild shop that says he has done marine engines. been around for 8 yrs. on his own and in the field for 20+ so I think he is ok. I will ask him to tell me the diff from auto to reverse marine and see how I feel about his answers.
So far everything is going great getting the eng ready to pull out of the boat without having to cut any openings, the only thing that kind of puzzles me is that the upper exhaust swivels are stamped 97257 but are actually 97386 elbows as far as I can determine and I find it hard to believe all 4 elbows are miss stamped. Pics are the first one is a 97257 and #2 & #3 are 97386 both like mine. Things that make ya say “ Hum”…….
Hey btw it has been like 30yrs or so since I torn anyengines down and put them back together so any suggestions on a good gasketsealer to use these days? and boltthread Loctite and hanks again !

Yes the seals are different but only the bottom end spins reverse due to the gear to gear timing set. I just did this rebuild on my reverse 454 a couple years back. I have all the parts numbers but they are in a file at the boat.

Where are you located and what type of boat do you have? If you re in the NE area I would recommend Reid Automotive in Whitman, Ma. The exhaust system parts used are somewhat dependent on how the engine sits in the boat in relation to the water line.

iWe are currently in Olympia WA, and Craig I would be greatfull if you could send me that info next time you get aboard . We have a 1987 Californian aft cabin 42ft, she has been a great live aboard for the last 5 year's but we going to start looking to cross over to a "Land Yacht" for new adventures in the next year or so. Well thanks again i have always received fantastic info from everyone here !