409 marine (boat motor/engine)

rstreet

Well Known Member
Supporting Member 14
#21
Johnny interesting motor you have! The Daytona Marine 409 conversions in early 60's were used by the early offshore racers as they were pretty heavy hitters back in the day. They did make regular lower horsepower conversions like several other marinizing companies did. The base horsepower was 280 from the 409 blocks and yes they were notched. The Daytona 400 was a twin turbo unit and from what I recall were just under 400 HP but possibly some were rated at 400 HP. I am assuming the exhaust system and turbo's from your's are long gone.
Robert
 

Johnny Pell

Well Known Member
#22
Hi Robert , it has the 333 heads on it and the block is notched, the engine builder put 10.5 to 1 pistons in it, and an isky 911 cam I'm running a 4gc from a 64 impala 340 horse motor, the motor runs real good but it has some noise issues, I know he ported the heads and put bigger valves in , the guy has done other motors for me but never a 409, I was thinking of using a different pan because of the capacity issue, I like the cast pan because I have it in my 64 K10, the cast pan is cool in the truck, I'm not sure what direction I should go at this point, ive taken long trips with it witout any problems but on cold start I have that noise, thanks for writing back
 

Don Jacks

Well Seasoned Member
Supporting Member 3
#23
Johnny,Were those pistons cast or forged? As to the valve train noise,you may need to adjust the valves again now that it has a few miles on it,or you may have too much oil in,and it's foaming due to crankshaft windage.In looking at the placement of the hole that you're using to gauge the level,if you imagine a line where the level would be straight along the pan,it's would be way too high up the pan.This will cause foaming once the oil is warmed up,causing noise in the hydraulic valve train.As to the cold noise,remove the plug wire from number 2 cylinder as the noise is occurring,if it doesn't change,you may have a fuel pump issue[don't laugh,I've seen a fuel pump do some crazy sh@t],if if does,it's likely a piston issue on number 2 or 4.If it has forged pistons in it,it may not be a big deal,as forgings are set up with a much looser clearance,and will sometimes make a little noise when cold until it warms up.
 

Johnny Pell

Well Known Member
#24
Hi Don, I think they are forged pistons, I have to take a look at the bill again, I ran the motor with the fuel pump completely off the motor and still heard the noise, I had a bad pump one time that made the same sound, I was hoping that was it, also, there isn't any change in the noise when I disconnect the plug, the noise is the loudest right where the block and head come together by the # 2 cyl , I was worried about the oil foaming that's why I started asking about the oil level , did you see the pic ? I was afraid to come all the way up to that plug in the pan I figured the would be too much oil, I've been running 7 quarts and its about 3/4 of an inch lower than the plug, I was to put more than 7 quarts, I wonder if there is any way to get the right dipstick for that pan ,
 

Don Jacks

Well Seasoned Member
Supporting Member 3
#25
Well the next time that you drain the oil,put 5 qts.in the pan plus 1 for the filter and see if the valve train noise goes away.The stock 340 horse pans held 4 qts,the high out put engines took 6.add 1 for the filter in either case.Since the knock goes away once the engine warms up,the knock is likely a piston-cylinder wall clearance issue and not necessarly a big deal as long as you take it easy on the engine until it warms up.
 
#27
My 409 engine used to be a reverse rotation marine engine. It now runs stock rotation and resides in my 1955 Chevy bel air. The crank is fine, the pistons are fine, the oil pan is fine. The camshaft has to go, as this is what makes it run backwards. The drive gear on the distributor has to be changed back to stock because the distributor gear on the camshaft is backwards so the distributor turns in the stock rotation. Even though the engine runs backwards the distributor turns stock so the oil pump also turns stock. Other than that I don't remember changing anything else. My engine has a 3/8 stroker crank and is overbored .125 yielding 479 (I round up and call it 480) cubic inches. I run Ross 9.5 compression pistons to deal with today's pump gas. The rotating assembly is internally balanced so I could run any flywheel of my choice which is a lightweight 15 pound 153 tooth L-88 BBC. The camshaft is an Isky Z-33, pushrods are Crane, rockers are Harland Sharp roller rockers. The intake is a Mickey Thompson crossram with two Holley 750 double pumpers. I have had no problems after changing it's rotation.
 
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RCampbell

Well Known Member
#28
I'm in the process of restoring a 1957 Biesemeyer V drive. The boat was converted to a 409 in the early 60's. I have a passenger car oil pan and would appreciate any photos of the various boat pans. I'm thinking a boat pan might be a nice addition....thanks Russ
 

rstreet

Well Known Member
Supporting Member 14
#38
These aren't the only ones to have two dipstick locations for twin applications. Ever tried to get the port side starter off if engine didn't have top mount starters!! Heck even starboard is hard on a deep V hull with full big stringers
 
#39
Interesting stuff here. I know this is an old thread but...
I have run across a 64 marine 409 from a twin-engine Chris Craft for sale. It had been the reverse rotation engine of the two that came out of the boat, and the guy has rebuilt the top end. New cam, etc. Also new intake (forgot to ask him about carburetor configuration), dist, starter, water pump, air cleaner, etc. in boxes. It was a closed cooling system, and he says the insides are as clean as when it was new. I think I'm going to make the 3 hour run to look at it this weekend to have a look at it, and maybe bring it home.
I know almost nothing about these engines, but the 348 in my truck is very tired and this engine is being offered to me at a good price.
Any information and/or advice would be appreciated.
 
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