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Reverse Rotation 318

Posted By: oldman

Reverse Rotation 318 - 05/11/13 02:31 AM

Now then would you revese the rods or not the piston will still notch forward, also does anybody know .
Posted By: RapidRobert

Re: Reverse Rotation 318 - 05/11/13 02:37 AM

Saw one in an inboard speedboat but never got into the innards. I'd assume with the reverse rotation changing the thrust sides that the piston offset (if present) would want to be reversed to keep it functioning
Posted By: oldman

Re: Reverse Rotation 318 - 05/11/13 02:46 AM

Quote:

Saw one in an inboard speedboat but never got into the innards. I'd assume with the reverse rotation changing the thrust sides that the piston offset (if present) would want to be reversed to keep it functioning




Yes thats what I'm working on a motor for a 1970 century Boat
Posted By: RapidRobert

Re: Reverse Rotation 318 - 05/11/13 02:48 AM

iirc the firing order was 2=1=8=4=3=6=5=7 & I'm not even sure about that. It was a strange duck
Posted By: CSK

Re: Reverse Rotation 318 - 05/11/13 02:50 AM

also polish the crank in the opposite direction
Posted By: Cab_Burge

Re: Reverse Rotation 318 - 05/11/13 04:48 AM

I had heard that Chrysler Marien and Grey Marine before them used reverse rotation Chrysler motors(of all size and type, flathead sizes to Hemi ) in a lot of the higher end cabin cruisers that had two motors in them, one ran clockwise and the other one went counter clockwise.That pratice is common on twin piston driven engine airplanes
Posted By: dynamite

Re: Reverse Rotation 318 - 05/11/13 12:02 PM

Reverse the pistons,notch to the back and leave the rods were they were..polish off the rear seal groves ..use the rope type seal..and the firing order is 1=2=7=5-6-3-4=8..
Posted By: oldman

Re: Reverse Rotation 318 - 05/13/13 01:41 AM

Yes I kow about the rope rear main, I was going to build a new engine engine, and I am running the engine in it now and know I have to have a new cam and the dist gear too so the oil pump will turn the right way , and have not been able to look at the old engine yet but got to have a cam custom ground since you want a cam in the 0- 4000 rpm range I am raising the compression with pistons and going with 340 heads everything else I'll use.
Posted By: dOoC

Re: Reverse Rotation 318 - 05/13/13 02:47 AM

KNOWING YOU oleHAM .... you would put this moder is the reverse locATION ....

..... like UP FRONT in da boat ...
Posted By: jjl

Re: Reverse Rotation 318 - 05/13/13 04:38 AM

I built a pair of poly's and a pair of late 318's that were in large boats.One each was reverse rotation,and what I remember was oil pump,cam,distributor,inter. shaft were different.These were purpose built from the factory.Water pumps,maybe also.
Posted By: B5 Bee

Re: Reverse Rotation 318 - 05/13/13 10:47 AM

All automotive are LH, left hand.
Many marine are RH, right hand, even in single engine boats. The RH prop torque thrust in a single engine small boat helps trim it back to level when one person is aboard (right side heavy).

Are you building a new motor off an automotive core? If so,
-reverse the pistons on the rods, not the rods on the crank
-polish out LH rear main knurling and use a neoprene seal not rope, if you have RH knurling leave it and use a rope seal
-use a reverse cam core, SB may be available new, BB isn't, besides location of lobes, the gear is cut backwards
-use a reverse dist/oil pump drive gear, this allows std oil pump
-use a marine thrust block between block and dist, the LH drive gear walks down against the block bushing, the RH drive gear tries to walk up so a thrust block is needed
-marine dist is special with spark arresting features, it does rotate the same direction as LH, just the wire order is reversed from 1-8-4-3-6-5-7-2 to 1-2-7-5-6-3-4-8
-marine carburater, alternator and starter are special with spark arresting features, carb uses spark arrester instead of an air cleaner
-water pump depends if it is raw water or heat exchanger cooled
-and of course the exhaust manifolds are water cooled

What model Century? What trans, Borg Warner or Paragon? Any pics?
Posted By: oldman

Re: Reverse Rotation 318 - 05/14/13 01:20 AM

Thank you B5 Bee thats the info I was looking for
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