Is there any problem putting an auto engine into a boat?

[ken_23434]

Re: Is there any problem putting an auto engine into a boat?

I have not messed with a cam in a Ford, but on the GM v-8's there is a "thrust plate" that is mounted behind the cam gear for the timing set. That thrust plate is there to keep the cam from walking forward or reverse. I don't fully understand why that is a problem on the roller cam and not the flat tappet type. I would assume the Ford engine would need something similar. If that's the case, you would just need to get the timing cover off to take a peak. Otherwise, if you pulled off the intake manifold, you can see the lifter valley. The roller lifters require this spider plate to hold them in place. As soon as the manifold was off, it would be obvious what type of lifter was installed.

As for swapping cams, it's not a complete tear down of the engine. In a much simplified procedure:

1. remove distributor
2. remove intake manifold
3. remove water pump
4. remove timing cover
5. remove timing set
6. remove valve covers and rocker arms
7. lift (or remove) lifters
8. pull out old cam.
9. Reverse for installation.

That covers the major steps.

 

[gadget73]

Re: Is there any problem putting an auto engine into a boat?

If you know the year and make of car the motor came from, I can probably tell you anything you'd want to know about it, including firing order, cylinder head type, camshaft type, etc.

One thing about Ford motors you really need to be aware of though is the camshafts. In 1986, Ford went to roller cams on all their car engines. Roller cams need a steel distributor gear, and flat tappet cams need an iron gear. Mixing these will cause problems. If you're lucky, the iron gear on the distributor shreds and you just replace the gear. If you're not lucky, the teeth on the camshaft self destruct and you have to replace the cam. Be aware of what you have, and what parts are in there or you may be in for trouble.

 

[Viking...]

Re: Is there any problem putting an auto engine into a boat?

Hey Brad,

The Ford small blocks that had interchangeable parts were the 289's and 302's.
302's have a bit longer stroke, so the blocks have longer skirts (it was ok to use 289 parts in your 302, but not so good the other way).
351's are a longer stroke than the 302's, but in the other direction (taller block), so the intake manifolds were not interchangeable.

When Ford changed the designation to 5.0L, as opposed to 302, the most notable feature was the addition of a roller cam.

Hydraulic lifters that opened over the .500" range required double and sometimes triple coil valve springs to avoid floating at higher rpm's.

The 5.0L Mustangs of the later 80's came stock with roller cams that launched those lifters over .600" (.612" iirc)...amazing to us amateur hot rodders

I was a bit puzzled about the firing order, since I'd never heard of a 302 using the 351 order. After a bit of searching, I found some info that might help.
Some truck and van engines used the 351 firing order in their 302 engines ('94 to '95 model years).

Perhaps you could find your casting number and date code - above the starter on the right hand side of the block.
Once you have that info, it will undoubtedly help you with your project, especially when ordering and cross-referencing parts.

I'm curious to find out what the cam profile is for the marine 302's. I'm going to do a bit of digging, see what I can find...

 

[Viking...]

Re: Is there any problem putting an auto engine into a boat?

Well, the cam profiles are just about what you'd expect for marine applications.

Since boat engines seem to run around the 5000 rpm mark for WOT, you'd want a camshaft that has very civilized numbers.

I'm finding a range of intake/exhaust number from about 250 to 270 degrees of duration. Lift is coming in at .430 to .460", for hydraulic lifters.

I think you could expect a very smooth idle by staying at the lower numbers.
Sacrificing a bit of smoothness would yield some horsepower gains, though not necessarily better performance.

Don't forget, a camshaft with more duration and lift, requires more fuel and air...which could mean more venturies and bigger intake ports! Oh the excitement

 

[Bcrowe]

Re: Is there any problem putting an auto engine into a boat?

Thanks to everyone for their imput on my "little" issue. Since my last post I spoke more with the guy i bought the boat from for some clarification. The engine that was originally in this boat was a ford 302 with a mercruiser 888 sterndrive. He told me that all of the parts of concern(starter,alternator, waterpump, intake manifold, exhaust manifolds, fuel pump, and carburater(sp?) from the original wrecked engine. He further explained that he bought and placed a new distributor, plugs, wires that are marine rated and for this engine. He said that he did not replace the freeze plugs, head gaskets or the cam and are all auto parts. I am guessing that he transfered the valve covers over because they have the mercruiser name on them as well as the original serial number plates on them. He said that when torn down the blocks looked identical and assumed there wouldnt be an issue with it. He stated that he spent a minimal amount of time trying to get it to run and gave up or got busy. I am going to go through the spark, firing and fuel recomendations in the adults only section and see if i can make progress...it is starting to sound like this could be a reasonably easy fix. I appreciate all of your help and information as far as durability and runability. I was going to add some pics for you but apparently they are too large.
Thanks again,
Brad

 

[Bcrowe]

Re: Is there any problem putting an auto engine into a boat?

Hey there everyone. I just wanted to take a second and let everyone know that i got the beast running. It ended up being a timing issue. Was a simple fix. At least that part was. The guy who put the engine in must have been high or something becuase there were all kinds of things either not connected or connected improperly. Anyhow thanks to all who gave me great advice on this problem couldnt have figured it out without you. YOu are all a godsend.

 

[zbadboy]

Re: Is there any problem putting an auto engine into a boat?

Great to hear you got it running. Its a great feeling and sound.