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Keithb87
06-06-2006, 08:19 AM
Memorial weekend we "Blew up" the 460 in the Condor. ( We have not tore it down yet. Too hot outside.) But A buddy of mine has a 460 from a 78 Truck the I might be able to pick up pretty cheap. It has 15 k on a rebuild before he rolled the truck and pulled the motor. I think it would slide right in with out any problems.
But Someone told me that a "Marine" Motor has high Nickel content and that a truck motor would not do as well. I'm thinking that if this is true it's probaly in like a Merc cruiser not in a 82 Jet boat with a BBF 460.
What's the concesus here?

IMPATIENT 1
06-06-2006, 08:51 AM
Memorial weekend we "Blew up" the 460 in the Condor. ( We have not tore it down yet. Too hot outside.) But A buddy of mine has a 460 from a 78 Truck the I might be able to pick up pretty cheap. It has 15 k on a rebuild before he rolled the truck and pulled the motor. I think it would slide right in with out any problems.
But Someone told me that a "Marine" Motor has high Nickel content and that a truck motor would not do as well. I'm thinking that if this is true it's probaly in like a Merc cruiser not in a 82 Jet boat with a BBF 460.
What's the concesus here?
its summer time, if its cheap and will get ya back on the water,run it.marine motors are built with different clearances/stronger parts,but if you take it easy on the truck motor,it'll hold.

stompnstang
06-06-2006, 09:33 AM
its summer time, if its cheap and will get ya back on the water,run it.marine motors are built with different clearances/stronger parts,but if you take it easy on the truck motor,it'll hold.
agrees with him i chunked the motor and in a haste to get it back in the water we used a motor str8 outta my friends truck and i ended up running almost two str8 summers with it. i did not beat it to hard and just nice boating and relaxing but she worked fine .. he has used it for two years of mud running since so i must not beat it up to bad

LakesOnly
06-06-2006, 09:43 AM
Memorial weekend we "Blew up" the 460 in the Condor. But A buddy of mine has a 460 from a 78 Truck...It has 15 k on a rebuild before he rolled the truck and pulled the motor.
But someone told me that a "Marine" Motor has high Nickel content and that a truck motor would not do as well. The parts that make up the marine 460's are the same parts used in the passenger car 460's. There is no high nickel marine block (all 429/460 blocks are "high" nickel), the cranks are the same, the rods are usually truck rods (which, technically, are no stronger than the passenger car rods), same D3VE heads, same valve train, etc. Find out if the rebuilt motor you are considering had a double-roller timing chain installed.
Using a passenger car engine that has the bearing clearances on the loose side of the 460's passenger car bearing spec's ought to work in a pleasure boat where you are not beating the hell out of the engine and trying to blow it up. A high performance application might dictate looser bearing clearances, but you'd be surprised what you can get away with in most low performance engine applications, regardless of manufacturer.
LO

Devilman
06-06-2006, 09:49 AM
Memorial weekend we "Blew up" the 460 in the Condor. ( We have not tore it down yet. Too hot outside.) But A buddy of mine has a 460 from a 78 Truck the I might be able to pick up pretty cheap. It has 15 k on a rebuild before he rolled the truck and pulled the motor. I think it would slide right in with out any problems.
But Someone told me that a "Marine" Motor has high Nickel content and that a truck motor would not do as well. I'm thinking that if this is true it's probaly in like a Merc cruiser not in a 82 Jet boat with a BBF 460.
What's the concesus here?
Have no fear, Keith. I did the exact same thing a year ago. Burned down my 429 & had some trips lined up so I pulled the motor out of my 4x4. Mildly built 460 with 8-9K miles on it, give or take. Swapped out a couple of items from the 429 to the 460 to make it jetboat-friendly & off I went. Still running it to this day, a year later. I don't run the holy hell out of it, but I don't baby it either. I been tryin to keep it under 4500 RPM it's been happy so far. :cool:

Some Kind Of Monster
06-06-2006, 12:24 PM
I just went through this on mine. There is a very good article in (I think) the April ***boat from TIMINATOR about the differences between marine and automotive applications. He explains that you can get away with a well worn car motor for awhile, but it will never run like a properly set up marine motor would. Do a search on the differences. I have my motor set up with the recommended loose bearing and cylendar clearances to allow for growth in marine motors that doesn't occur in a car. Also the double roller timing, stainless valves, hi vol oil pump, high capacity oil pan (a must), and a marine cam ground to have the power curve "come in" when a jet needs it are all things I considered. All in all, I say just put the car motor in and make a couple changes (oil pan, etc) and run it carefully until it dies. Then consider building a real marine motor.

Keithb87
06-06-2006, 12:29 PM
Thanks for all the help. I'll keep you posted on Progress. :)

loudpipessavelives
06-06-2006, 05:41 PM
the rods are usually truck rods (which, technically, are no stronger than the passenger car rods), LO
i was reading in a magazine that the truck rods are stronger, they were rebuilding a 460 and they pointed it out, I'm no mechanic i was juwst pointing out what i had read

IMPATIENT 1
06-06-2006, 06:05 PM
i was reading in a magazine that the truck rods are stronger, they were rebuilding a 460 and they pointed it out, I'm no mechanic i was juwst pointing out what i had read
i've read that too, but as cheap as h-beam rods are these days, why chance it?
good cheap set of h-beam rods :350-375.00
slung stock rod and sunk boat :priceless!

LGCDEVIL
06-07-2006, 05:38 AM
Bigsley here on the boards just got 6 or 7 hard seasons out of a $700.00 Wayne's short block. 460 ford truck motor. Tore it down this winter. Bearings & cylinders weren't pretty, but probably could have squeezed another season out of it.

396_WAYS_TO_SPIT
06-07-2006, 02:49 PM
Do it right the first time!!!!! If its halfassed then you will run into problems sooner or later!!
One word for this pic......CHEAP PARTS!!!!!!!
http://www.***boat.com/image_center/data/500/2928CIMG1464.jpg

cave
06-07-2006, 05:23 PM
Man this thread makes me nervous. I bought a 4 bolt main dble roller timing gear 454 crate motor 6 years ago. All I added was Dooley 10 qrt oil pan. With 6 season you would think there is plenty of clearance inside :D
I baby the motor. I can hit 4200 rpms but run at 3900. Ask 396. I'm the slow boat out there but have a good time jet boating just the same. That will be next seasons project, if it last this season.

396_WAYS_TO_SPIT
06-07-2006, 08:58 PM
Jimmy, your boat is TURNKEY!!!!! All you have to do is put gas in and roll. Me on the other hand , will always have that slight doubt in my mind about my motor:eek: I just hope it never granades or I will be :cry: :cry: :cry: I have some coin in my mill...