SoCal Jet Boats
Tech Talk => Projects => Topic started by: Tatethiel on February 01, 2016, 03:46:08 PM
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I recently purchased a 1978 almar jet boat. 19' has a 753 Hamilton pump and an olds 350 for engine. The motor in the boat has a spun bearing, is bored .30 over. My question is, due to the rarity of an olds 350 in boats it seems, do I rebuild this motor or repower it with something else?. I can't seem to find much info on the olds 350 in a boat application. Any help would be awesome. I just want to use the boat for cruising river and playing on lakes, nothing fancy.
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Get ready
Everyone is gong to tell you switch to bbc
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Not what I want to hear lol. I don't really want to change all of that stuff. What I would like to hear is "ya I had an olds 350 in a boat before" rebuild it you will be fine.....
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a olds 350 is the same physical size as a 455 olds, it will bolt right in with the same hardware, even the exhaust
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I thought a 455 is taller and wider. Are intakes the same? What's weight difference?
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the intake will not fit as the block is a little wider, to accept the larger crank, heads will interchange, cam, pan, dist. etc. weight is pretty close
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I guess that would be an option, motor mounts and bellhousing same too?
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What are the drawbacks of rebuilding the 350? I know its a 2 bolt main motor, and has the funky web block. But if I did rebuild it, I'm trying to figure out longevity I guess holding a 3500 rpm
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Yes!!
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I can't find enough info to fell confident about rebuilding it and using it
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Just less power with the 350
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Most of the marine crap will swap over to a 455. Might be able to score a deal on a build able motor for a good price.
All dependent on how handy you are I would build a 454.
The issue is you will need to scare up all new mounts and marine gear. At that point, might as well build an LSX.
It's only money bro.
GT
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Also, there are a zillion (give or take) 350 Olds motors out there. We have had three over the years.
You should be able to buy an engine kit for that 350 for under a grand and likely spend another $300 on machine work, be good as new.
That Hamilton pump will make really good use of the HP you will have.
JMO, you won't even get close to spending the money you would doing a swap.
The 350 Olds, stock, makes about 270hp. The 455 about 330.
Good luck.
Got any pictures? Never heard of your combo.
GT
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If you run across a D or DX block, let know please. Kinda Olds nut here. Thanks sir!
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So gt you are saying give the olds a shot?
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So gt you are saying give the olds a shot?
Well, why not?
You should be able to build it (providing you are able to do a lot of the work yourself) with a relatively small budget (when compared to a swap).
Do you know what caused the bearing issue? (I bet I do).
A 455 might be a better move, but you already have the 350. You may run into exhaust outlet location issues if you go to a 455.
If you want to get back on the water for just a little bit of money (again, speaking relatively) is a no brainer.
The 3,500 rpm cap may be a little conservative. Call it 4,200 and I would say with a good oil pan and quality rebuild, should run a good long time.
JMHO
GT
Sent from my SCH-I545 using SoCal Jet Boats mobile app
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Thanks gt. I'll do some research on the oiling issues too. A good shop should know all about it.
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Thanks gt. I'll do some research on the oiling issues too. A good shop should know all about it.
GT MacGyver is wise. He will lead you to the promise land.