409 marine (boat motor/engine)

MoboMac

Well Known Member
#1
Going to look at a 409 for sale....posted previously.......and found out it was taken out of a boat....running reverse rotation..

This is what I have learned about marine engines;

They rust from the inside out.....so we need to pull the frost plugs to look for FeO2...

The crank is not suitable for standard rotation....as the rear main seal journal has reverse grooves cut in it for oil control...

Camshaft,timing gears/chain,oil pan,exhaust manifolds,carb and intake are prolly NOT suitable for a car installation..

Seller says that pistons pin holes are concentric...and NOT offset.....is this the case with ALL 409 pistons?

I stand to be corrected on info I posted ....and if anybody has anything to add....please DO.
 

rstreet

Well Known Member
Supporting Member 13
#2
I would not dismiss the oil pan or cam depending who marinized the engine as Dayton Marine made some strong engines back in the day for offshore performance use with cast covers and pans. True most conversions I have seen used notched blocks and 833 heads and steel covers rated at 280 HP. Some prop rotation changes were accomplished in the Borg Warner trans not in cam so verify.
Robert
 

Don Jacks

Well Seasoned Member
Supporting Member 3
#4
As to the crank,while some brands and displacements of engines do have oil grooves[Fords],not all do.I've never seen a Chevrolet engine with them.I don't see a problem here.The off set on the pistons was done to make the engine quieter for passenger car use,no biggie.The oil pan may or may not work for a car.As to the other parts such as cam,dist.,timing chain set, manifolds,these are parts that you're going to have to replace anyway,so I wouldn't worry about that part of it.
 

MoboMac

Well Known Member
#6
As to the crank,while some brands and displacements of engines do have oil grooves[Fords],not all do.I've never seen a Chevrolet engine with them.I don't see a problem here.The off set on the pistons was done to make the engine quieter for passenger car use,no biggie.The oil pan may or may not work for a car.As to the other parts such as cam,dist.,timing chain set, manifolds,these are parts that you're going to have to replace anyway,so I wouldn't worry about that part of it.
Ok....so the piston pin holes ARE offset?

Spoke with Marvin @ Tradex today.....and he indicated that 409 right side and left side pistons are different?

Perhaps they are installed in the opposite sides in reverse rotation engines?
 

BSL409

Well Known Member
Supporting Member 6
#7
Ok....so the piston pin holes ARE offset?

Spoke with Marvin @ Tradex today.....and he indicated that 409 right side and left side pistons are different? NO NO

Perhaps they are installed in the opposite sides in reverse rotation engines?
NO Different on the 409 pistons. I have two marine 409 engines a right & left, you would only need to change cam lifters timing chain & gear and
distributor, not that you would want to use those old pistons anyway
 

MoboMac

Well Known Member
#8
NO Different on the 409 pistons. I have two marine 409 engines a right & left, you would only need to change cam lifters timing chain & gear and
distributor, not that you would want to use those old pistons anyway

Just that simple...?
That's good to know....

I'll report back when I go to check it out....
 

Johnny Pell

Well Known Member
#9
I would not dismiss the oil pan or cam depending who marinized the engine as Dayton Marine made some strong engines back in the day for offshore performance use with cast covers and pans. True most conversions I have seen used notched blocks and 833 heads and steel covers rated at 280 HP. Some prop rotation changes were accomplished in the Borg Warner trans not in cam so verify.
Robert
Hi I have a cast marine pan on my 409, do you know what the correct capacity is? Thanks any info appreciated
John
 

MRHP

 
Supporting Member 1
#10
Can you post a picture of your pan, there were many options. I have one that is 12-14 quarts. Some are 5-6 quarts.
 

Johnny Pell

Well Known Member
#15
There are two plugs on each side of the pan I had one of them out, I put 7quarts in and the level wasn't up to the plug, I've been running 7 quarts, I made up my own dipstick tube, I'm not sure if I'm right or wrong .
 

Johnny Pell

Well Known Member
#17
Thanks you very much, I've been running 7 quarts, I just wanted to make sure i don't cause any damage, i haven't been happy with this engine since i put it in , its got a noise when its cold, sounds like piston slap and when its warm the valve trane is noisey, at some point ill have to pull it and get it to another engine builder, I'm not sure if i want to bring it back to the guy who originally did it .
 

Don Jacks

Well Seasoned Member
Supporting Member 3
#18
What was supposed to have been replaced when the engine was "built"?On your oil pan,are the holes in the pan in approximately the same place[level],or is the one on the right[pass] side lower than the one on the left? If the rt.side is lower,then that one would likely be the point where one could need to add oil.
 

BSL409

Well Known Member
Supporting Member 6
#19
Here is the pic of the Motor when I got it, I wish I could find some info on it
I would say about 6-7 at the most your oil pan looks very close to a standard 409 pan size other than where the dipstick tube is on your pan is way up at the top of the rail
and on a stock 409 pan is down farther on the side of the pan
 

Johnny Pell

Well Known Member
#20
Hi Don
both holes are at the same level, I had the plugs out and after putting in 7 quarts the level was just below the holes, when the motor was rebuilt he put in new pistons, Cam , all new valves new rods new oil pump timing chain, the motor runs great but it a little noisy for my liking< when its cold I have noise near the 2 nd cylinder , as soon as it warms up it goes away, but the funny thing is, when I start it cold I don't hear the noise until the oil pressure comes up, and the valves are noisy when its warm
 
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