1997 5.7L thunderbolt ignition. Slow crank

[findinghomer]

Oh and if I am able to do this, can change into one that's fuel injected? Or will that give me a bunch of incompatible headaches?

 

[nola mike]

Oh and if I am able to do this, can change into one that's fuel injected? Or will that give me a bunch of incompatible headaches?

A truck cam works fine, may need a composite head gasket and brass core plugs, though my 2003 block already had both. Stick with a carb. Your 97 may or may not be a vortec engine. If you got a newer vortec block and combine it with a 4bbl carb that would be a nice upgrade. Otherwise you'd need a non vortec block or swap your heads over.

 

[findinghomer]

A truck cam works fine, may need a composite head gasket and brass core plugs, though my 2003 block already had both. Stick with a carb. Your 97 may or may not be a vortec engine. If you got a newer vortec block and combine it with a 4bbl carb that would be a nice upgrade. Otherwise you'd need a non vortec block or swap your heads over.

Here are a couple pictures from inside of my spark plug hole.. is that yellow stuff rust? I did spray WD-40 in all of the spark plug holes. And should those be in that position?

 

[findinghomer]

If those tell you anything and you need some better pictures I can get some later it just got really hot out and I couldn't concentrate getting a better shot, my camera it's not that great

 

[alldodge]

Looks like rust to be

 

[findinghomer]

Looks like rust to be

Is it worth squirting some PB blaster in there?

 

[alldodge]

Is it worth squirting some PB blaster in there?

No
Your motor is acting like a bull dozer I bought. It would crank but only slowly. After doing most of the stuff you did, I pulled the valve cover like Mike mentioned and found water. After that I pulled, rebuilt and reinstalled the motor.

The cylinder walls were rusted up bad. This is why I wondered if the oil level was correct. Water floats to the bottom and you will not see it on the dipstick but it will raise the level

 

[alldodge]

CAT 3204 motor

 

[findinghomer]

CAT 32View attachment 417815View attachment 417816View attachment 41781704 motor

Oh wow, nice work! So the first picture is with the valve cover off the second picture is with the head removed?

 

[alldodge]

Yes

 

[findinghomer]

Yes

Ok. So I guess I'm going to start working on trying to find a new engine, And plan for eventually replacing it. But just out of curiosity on compatibility, if I were to find something like this , which looks like it's a complete drop in engine with all of the accessories , hoses, cables etc already attached and complete , this will bolt right into my boat since I'm taking a 350 out of it?
But I to were get one used from a salvage yard out of a vehicle, the base block will bolt right in, but I may need to scrounge around looking for mercruiser parts because my old ones may not bolt to that particular engine?

 

[alldodge]

if I were to find something like this , which looks like it's a complete drop in engine with all of the accessories , hoses, cables etc already attached and complete , this will bolt right into my boat since I'm taking a 350 out of it?

2 things
1 maybe but maybe not, it depends what the serial numbers is. Appears to be fuel injected and that's ok, but need to know if it has 10 or 14 pin engine connector? Also is it cable or digital controls?

2 that's pretty cheep for a new drop in motor, so is it new or is it something that has issues and just looks new?

 

[findinghomer]

2 things
1 maybe but maybe not, it depends what the serial numbers is. Appears to be fuel injected and that's ok, but need to know if it has 10 or 14 pin engine connector? Also is it cable or digital controls?

2 that's pretty cheep for a new drop in motor, so is it new or is it something that has issues and just looks new?

Oh ok, so need to know the configuration of the main harness? I guess that's what runs to the dash? So I would need to know if it's one of those 2 configurations, so any 350 V8 out of a truck would be one of those 2, and I just need to make sure it fits my plug? And I didnt know there was digital controls lol. I wasn't putting serious thought into buying that it just came across my feed and I thought..... "Hmmmm if I can repower in that price range I'd be ok, I wonder if it's easy as just finding any drop in 350" so figured id ask to get a better understanding of my options

 

[alldodge]

any 350 V8 out of a truck would be one of those 2

Partly another 2 different things

1 We were talking about a Mercruiser in your pic which can have a few different configurations, so make sure if you buy a boat motor it fits your harness. This is not to say you can also replace your boat harness and install any motor

2 If your getting a truck V8 from a junk yard (or reman short or long block), than this is not an issue with wiring. Your old boat wiring will work on the newer motor. The only possible issue is you "might" not have bolt holes where your older stuff would need to bolt up to. Not saying this will happen just something to keep in mind. The worst case is you would need to get some different brackets

 

[findinghomer]

CAT 32View attachment 417815View attachment 417816View attachment 41781704 motor

Ok took the port valve cover off. I don't see water and oil looks good . I don't know how to tell if valves are bent , bad or whatever, but they all have movement, but these two. They all have a little movement but these don't move at all.

 

[findinghomer]

Could be sticking valves as well (less likely if you can't turn with plugs out) or seized ps pump/alt. I'd remove belts, check oil, pull valve covers. But agree that if you can't turn it by hand you've got problems

Pulled valve cover. Those two have no movement The rest have movement 

 

[findinghomer]

Welp. Disregard those, I don't really know anything about an engine I guess that's just the position the Pistons were in when I shut the engine off. Took the other side off and same thing so I turned the engine over a little bit and I see they move. All of the valves are moving properly on both sides

 

[cwella]

Hi guys Okay I've done a lot of research on the internet and iboat, and I'm stumped still. Hoping someone could steer me in the right direction with my individual problem. Took the boat out of storage from winter, everything fired up just fine, Strong crank and fired with minimal effort. went on the lake everything was fine except for a few hard starts went hot. I got it home to try to diagnose that problem and ran it on muffs , it fired right up nice and strong. I let it get to temperature so I can try a warm start by shutting it off and then restarting it 10 or 15 minutes later. I did that, and now I have a really slow crank as if I have a low battery. I know the batteries are 100% charged I even pulled the working battery out of my truck for testing, same issue. Figured I had a starter issue, because I replace it with an aftermarket one 7 years ago. So I just went ahead and got another one. Even with the brand new starter, it's still cranking slow. So I pulled all the plugs, no water came out, cranked it with the plugs out still cranks slow. My next step was to check all of my connections, I did notice one of my battery terminals was loose out of the eyelet. Figured that was my problem, so I redid it. Now it's nice and tight and even greased up. Still a slow crank. So I figured I should just redo all of my battery connections including to the starter, or maybe it's my ground? So I traced my ground wire on my battery, apparently the ground wire attaches to battery one, and just loops behind the engine attaches to the ground of the other battery, it's not grounded to the engine? Is that normal? I know that cable did short out about 10 years ago and melted the insulation to it, but being that it was just a ground cable I never fixed it. I'm thinking this could have something to do with it as well, but shouldn't it be attached to the engine? This is where I'm really confused now , the negative posts on each battery just attach to each other. I found the ground strap, there are two grounds coming off of them they are smaller wires, can't see where they go maybe a ground bus? the ground seems nice and tight but I just don't understand why the batteries aren't grounded lol. Anyway I'm pretty stuck and I got a boating trip in a couple weeks and I'd like to try to get it fixed so I figured I would reach out hoping someone can help me. Thanks!

A bad ground connection sounds like a strong possibility, especially since the cable was previously damaged. The batteries should have a solid negative connection to the engine block, not just to each other. I’d check and clean the battery terminals, engine ground connection, and starter connections with a voltage drop test while cranking. A cable can look fine but still fail under load. I’d replace that damaged ground cable before chasing anything else.

 

[findinghomer]

A bad ground connection sounds like a strong possibility, especially since the cable was previously damaged. The batteries should have a solid negative connection to the engine block, not just to each other. I’d check and clean the battery terminals, engine ground connection, and starter connections with a voltage drop test while cranking. A cable can look fine but still fail under load. I’d replace that damaged ground cable before chasing anything else.

I do get a voltage drop when the starter cranks at the solenoid and at the starter. But I can't turn the engine by hand anyway that's why I'm leaning towards internal damage. And those cables were just fine the day before all this happened

 

[cwella]

If you can’t turn the engine by hand, I’d also be leaning toward something mechanical. The voltage drop could just be the starter pulling hard against a locked engine. Since the cables worked fine the day before, I’d check the simple things first (starter, connections, possible hydraulic lock), but if those check out, internal damage seems likely.