Used boat project, need engine info 302V8

jasonnb

Petty Officer 2nd Class
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Nov 8, 2001
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171
I'm lookin at a bot that has a '76 302 v8 which is dead (outdrive supposed to be in fine shape. Cause of death was cylinder rust. Owner says boat sat in dry storage for the last 16 years after only being used a couple times a year since new. I'm trying to get a handle on what this would cost to fix properly before deciding if I want to buy this boat. I am assuming complete engine replacement at minimum. What about risers/manifolds? any other items to consider? The price is reasonable, maybe....
 

Bob_VT

Moderator & Unofficial iBoats Historian
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May 19, 2001
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Re: Used boat project, need engine info 302V8

If it is a good block you can probably get it bored 30 over and buy a rebuild kit and do it yourself...new pistons, rings, bearings, gaskets for about $600.00 (your labor) or look around for a reman'd block (plenty of marine blocks available on the net). The risers and manifolds might still be good...you will just have to decide. If you are not prepared for the commitment then keep on shopping.<br /><br />Bob
 

jasonnb

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Re: Used boat project, need engine info 302V8

Thanks Bob. If it is rebuildable, my brother is a mechanic, just doesn't do it for a living anymore. I just don't know if it's rebuildable. The owner said his mechanic pulled a spark plug and declared the engine junk. My concern is mainly risers/manifolds. The engine is fairly easy, but those things are pricy.
 

Saperry

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Nov 13, 2001
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99
Re: Used boat project, need engine info 302V8

If the boat was in dry (out of the weather storage)why is thier water in the motor? Is the motor"stuck"? 302's are simple motors to rebuild and the block is not cracked it can be rebuilt. If the motor is stuck it makes it a little harder but it can de done. The big question is where did the water come from?
 

jasonnb

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Re: Used boat project, need engine info 302V8

Saperry, that's my big question. The owner doesn't know. I take it that he just wants rid of it. Fortunately, I can get cheap labor (lunch/dinner for a weekend or two, isn't having a capable mechanic in the family grand!). Is it possible that some piece of rubber dryrotted and failed and let the water in after the current owner used it for a couple months? I'm assuming that the worst case is a rebuilt long block and a set of manifolds/risers. The boat was primarily fresh water, with a few uses in a fresh/salt bay. The mechanic that pronounced it dead did so by pulling a plug.
 

Alrobot

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Mar 24, 2002
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Re: Used boat project, need engine info 302V8

I think its time to check with a different mechanic. The engine is probably toast, but to tell by pulling a plug. Let me guess, he had one to sell you. Anyhow, my 2 cents worth is there are a lot of wrecked Mustangs out there with 302's many are roller cam motors pushing 215 horses with a decent four barrel and not a whole lot of tinkering. If you add stuff like a better cam and roller rockers your above 250 easy. I bought a 76 Galaxy because it had a 302 and I could do the swap in a weekend if need be. If you like the boat, by all means GO FOR IT, just make sure you are not settling just because you want a boat, in that case, keep looking...
 

Saperry

Petty Officer 3rd Class
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Nov 13, 2001
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Re: Used boat project, need engine info 302V8

The last 302 I built (about two years ago) cost about $1800.00 from bare block. It was for a 69 mustang that my brother owns. I was the cheap labor. We went a little exotic with hypereuretic pistons,matched eddlebrock cam and intake, fully adj. valves, roller rockers, guide plates etc. The it will push around 340-350 hp now and he is happy. <br />The block we used was a 74 model that I bought for $15.00. It was sitting out in the rain and we had to drive a couple of pistons out with a hmmer handle. A trip to the machine shop had it punched .050 over and the crank turned .010/.010.<br />I even had the parts shipped to the machine shop.<br />Machine work and labor to build the block was about $175.00.<br />My point is if the block is not cracked you are ok. Manifolds/riser will prob be ok just clean them up. The orig. 302 that was running when it came out is sitting in the back of his garage wrapped in plastic. We just used a different block to keep the orig. intact.
 

jasonnb

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171
Re: Used boat project, need engine info 302V8

Thanks Saperry, I decided to take the chance and buy the boat. I'm hoping the block is ok, or at least can be bored. I did find out that the ex. elbows were replaced last year along with the ex. bellows. I'm wondering if the goofed something and let water in.<br /><br />Thanks too Big Al, the current/previous owner was the one who passed along that info. My brother suspects the engine would be a rebuild. Worst case, would be to pick up another block. My fear is adding HP is I don't want to stress the outdrive.
 
D

DJ

Guest
Re: Used boat project, need engine info 302V8

Jason,<br /><br />Is this an I/O? If so, I BELIEVE the Mercruisers had a flapper in the exhaust to keep water from backing up into the manifolds when reversing or coming down off plane (backwash). Those might be gone, dried up, etc. Should be easy enough to check if you have the engine out.
 

jasonnb

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Re: Used boat project, need engine info 302V8

Thanks for the info Djohns. It is an 888 IO as best I can tell.
 
D

DJ

Guest
Re: Used boat project, need engine info 302V8

Jason,<br /><br />I thought it might be a "triple 8". I believe it has them. That was a nice package. A bit underpowered in some applications. The drive can "stand" a few more ponies if you're careful with it.<br /><br />The 5.0L lends itself well to minor mod's. that are not expensive.<br /><br />If you get into carburetion or distributor mod's. make SURE you stay with approved marine parts.
 
D

DJ

Guest
Re: Used boat project, need engine info 302V8

Jason,<br /><br />Couple more thoughts.<br /><br />1. Stay away from "lumpy" camshafts in this package. A lumpy idle plays havoc with the flywheel and driveshaft splines.<br /><br />2. Use stainless or brass casting (freeze) plugs on the engine. The automotive types will rot away in short order.
 

jasonnb

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Nov 8, 2001
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171
Re: Used boat project, need engine info 302V8

It's purely astounding how much info you guys have. Djohns, I was hoping the drive could stand a bit more hp. Nothing radical, maybe 205-210 so I could still maintain reasonable fuel economy.
 

Saperry

Petty Officer 3rd Class
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Nov 13, 2001
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99
Re: Used boat project, need engine info 302V8

If that drive will stand the HP increase (205-210), that is easy to make with a 302. Little more carb and some valve lift will do it easy. but you need to be carefull with your cam. BE SURE to use one designed for marine engines. The valve overlap becomes very important when your exhuast is submereged. I really do not know alot abouth the differances between marine and auto engines but corrossion is a big factor. Freeze plugs must be for marine use or you will be changing them often. Also the water pump is likley different since you are not using a radiator and cannot use antifreeze which also prevents corrosion of the cooling system. different thermostat etc. Ingnition sysem must be water tight. Marine carb etc. Also some 302 are externally ballanced and some are not so your flywheel and balancer must match your crankshaft.<br />Your best bet would be to rebuild your block instand of exchange for prebuilt longblock. That will ensure everthing is still matched on your lower end. If that moter has as few hrs as you say(or were told) and is not stuck, you should be able to use your old pistons and not bore the engine. Depends on how bad the water damage is. I don't know how you cuold tell from pulling one spark plug.<br />It is time to be on the water. If it was mine, even if the moter was stuck, I would:<br /><br />1. pull all the plugs<br />2. 4-5 good healthy squits of penetrating oil or<br /> WD-40 on top of the cyls.<br />3. Turn moter over (first by hand then <br /> with starter) may require long breaker <br /> at first. May need to let it sit a day or two<br /> with oil on cyls. just get the motor turning<br /> if it sounds good by hand hook up the starter.<br /> if it still sounds ok run a compression test.<br /> if the compression is good proceed if not drop<br /> back ten yards and punt it to the rebuid shop.<br />4. Remove/disassemble/clean/reintall carb <br />3. Change oil and filter<br />5. service out drive make sure exhaust is working<br /> properly<br />6. check ignition system for good spark<br />7. replace spark plugs<br />8. drain old fuel, clean out tank, add few<br /> gallons fresh motion potion and berryman B-12<br />9. spray shot of stating fluid down carb<br />10.some where in here you need to hook up water<br /> hose to engine<br />11.fire that mutha up<br />12.tune out the engine grab a life jacket and <br /> head for the lake
 

Saperry

Petty Officer 3rd Class
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Re: Used boat project, need engine info 302V8

Just wondering what became of this old ford V8<br />^
 
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