Worst boat buying fear come true ADVICE Please

[ToFastToCare]

I poted a few weeks ago about a 1996 SNOB I was looking at buying. I was able to work a price out with the owner and bought the boat. I picked it up last Sat. It is getting cold here in Utah, so I was hoping to get it out once before winter came.

When I got home I pulled the two block drain plugs and the exhaust manifold plugs because we have been having some below 32 nights. I also completely removed the raw water strainer and cleaned the weeds out of both sides of it. The previous owner had used it in a river that had lots of weeds. He had used it a day or two before i picked it up. I also cleaned out the transmission fluid cooler. Drained some water out of the hose running up to the crank driven impeller.

Put everything back together the next day and took it out. Dropped it in the water and started it up, checked for leaks. Idled the boat about 5 mins in place and then idled out of the no wake zone for about a min. I took off a, had the boat at about 4K for 45 seconds and the motor died. There was white smoke and a little blue smoke coming out the exhaust when I looked back.

When I tried to start it again the starter turned but the motor would not turn over. Locked up. I felt the hose coming out of the impeller going to the engine and it had some water in it but was not full. The oil level was right where it should be. Got towed in and took the boat home.

When I got home I pulled the block drains and got 3 or 4 gallons of water out. The I pulled the manifold drains and got a little sand (1 tablespoon) and some scale. Pulled the impeller apart and it was completly shreded. The pieces of it were sitting in the hose exiting the impeller.

The motor was still locked up so I pulled all of the plugs out. There was water in all 8 cylinders. I am guessing I have some bent connecting rods. The engine only turns a quarter turn by hand and I am unable to turn it any further using a ratchet.

I have an idea about what happend but I am looking for other thoughts. The boat has been to a marina every year, but I recently found out that the boat was not winterized each year (not really an issue since it was stored in a heated garage) and that the owner recalls maybe having the impeller changed 9 seasons ago.

Sorry for the long post, but I really need to figure out what happend and where I need to go from here, or what else I need to inspect to figure this out.

Thanks

Thanks

[TRDon]

find a new motor. What happened sucks but kind of irrelevent now. I am guessing cracked block that showed itself when you loaded it on the water. I am willing to bet the guy who sold it would act supprised and claim ignorance. was it overheating before that happened?

[DanielC]

Did you test drive the boat before you paid for it, and towed it home?

[ToFastToCare]

I skied behind the boat twice before I bought it. The temp gage was at 120 after we had been out for awhile. It may not be working. Do the gage and the ECU use the same temp sensor? It would have shut itself down if it had overheated as long as the temp sensor was working correctly. I met the previous owner half way between my house and his and trailered it the rest of the way home.

[intrlaz]

Same thing happened to me after I bought my boat. Engine blew after the first few times out. I was able to get a used zr6 from Correct Craft that they had been using to test new hulls. Had about 100 hrs on it. Also, you might be able to find someone to salvage the old motor. I got 1500 for mine.

[swc5150]

If it was running fine right before you bought it, I'd say you got extremely unlucky. I feel horrible for you, as your search is now on for a new motor. Did you happen to see the temp gauge reading when the engine stopped? They peg pretty quickly once the water supply is cut off, and it should've blasted a loud beep at you.

[teamseal]

There is a 660 hour 330 excalibur listed over on CCF!

[ToFastToCare]

That engine would work in my boat? It would probably take some harness splicing to get it to work. The temp gauge was around 120 deg when I looked at it. This was with the boat off and the key on. The red warning light did come on a little while after the engine stopped, but I figured it was because the key was on and the engine was off. No oil pressure when the engine is off. When I drained the manifolds there was scale that came out, unlike when I had drained it the day before.

I ran water directly into each manifold water inlet and removed the T-stat housing and filled the block with water. I figured there was a crack somewhere that let the water into all cylinders. Didn't find anything. I used hot water tap water when I did this. It freed the engine up and it turns over now with hot water in the block. I don't know how I ended up with water in the engine, but I think what happened was the old impeller wasn't able to prime itself quickly enough, self destructed, then one of the pistons seized in the bore. Maybe I do have a crack or a leaking gasket that only shows itself when the motor is really hot. There is some white residue on the outside of the exhaust manifold originating from the gasket between the manifold and riser.

I suspect the temp gauge doesn't work right, or didn't work because it was trying to sense air temperature instead of water temperature.

This has been a very frustrating first boat buying experience, but even with it broken and sitting in the garage I am still very happy to own it!

[teamseal]

PCM does not offer a Ford repower anymore so what they did was come up with a few real neat adapter items that will set a Excalibur right where your Ford was, no problems have done many in the past three years also a re-rout of fuel lines other wise direct replacement.

[ToFastToCare]

Wow, that is surprising. I probably should have mentioned I don't have a Ford. It has the TBI Chevrolet 350.

[WakeSlayer]

so it was already re-powered once.....

[swc5150]

Was the 350 Apex available in '96? Of course, he said TBI, and I believe the Apex was multi port.

[maxpower220]

I would suspect an issue with the exhaust manifolds and not the engine block. If the manifold has some rust or structure issues, it would allow water back into the block. However, the odds that both manifolds fail at the same time it unlikely. This issue may have started since you drained everything allowing some movement.

Regardless of how you handle the engine, make sure that inspect or replace the manifolds prior to starting you new engine.
Sorry you are having bad luck.

[LT206]

Here is a possible scenario:

After you drained the system following your purchase, the block and hoses were no longer full of water and thus the cooling system no longer primed. While all the interior surfaces in the manifold were exposed to air, the rust in there let go a little (that's why you are seeing scale when you drained them a second time.) In my experience this is normal after having the block/manifolds dry for a period of time. Sand is also pretty common if the boat has been run in shallow water and allowed to suck dirt/sand into the cooling system.

When you put it all back together you unknowingly did not get things completely tight or sealed, (an easy one to forget is the seal at the raw water intake filter) and when you put it back in the water the VERY old impellor was too weak to prime the system over all the air leaks. Heck, I've had new impellers that couldn't prime themselves over the air leaks. Sidenote: Anytime after I drain my system, I ALWAYS hook it up to the waterhose to prime the system before putting it in the lake. I just don't trust it to prime itself - and don't trust myself to have put it together perfectly air leak free....

On cool days, I've seen motors run for 5 minutes (of course the impeller blows up in less than one minute) with no water going to them not get too hot and appear to be cooling fine. This is what you saw as you idled out of the no wake zone. Then when you hit it - 4K RPM out of the hole on a cold motor probably not the best thing either, you quickly overheated the engine and it locked up. When it locked up, the valves opened slightly and allowed what little water was in the manifolds to suck back into the cylinders. I'm betting you don't have a cracked block, just an overheated one.

I would change the oil, change the impeller, find all the pieces of the impeller that are still in the cooling system, hook the waterhose to it and fire it up in the drive way and see what happens. You may find that there is only a few melted hoses at the exhaust manifolds. Get it running quickly (if it will) though, since water in the cylinders is not good and you need oil back in there as soon as possible.

[ToFastToCare]

What is meant by a "re-power"?

LT206: In the future I am going to be sure to prime the system with water. The boat I skied behind growing up and my fathers boat never got primed when they were put in the water at the beginning of the season, so that is why I didn't do it. I agree that the motor could just be overheated, but there was a small glass full of water in most of the cylinders. I got most of the water out of the cylinders and left the plugs out so the rest can evaporate.

I think the scale that came out the second time I drained it was from the overheat. The manifolds got hotter than they had been before; the metal expanded more than it had before and shed the scale off. I find it unlikely they both cracked allowing raw water into the cylinder through the exhaust valve, but if they saw the same overheat temperatures they are both going to behave the same since they are made from the same material and are the same age. From what I understand there is no way for water to get into the exhaust manifold unless there is a crack or a bad riser gasket. I plan on having the manifolds checked or replacing them.

Something else that is confusing me is how the engine continued to run if there was water in the cylinders. This indicates to me that it rushed in all at once. There is no flap covering my exhaust, should there be? Is it possible for water to have come all the way back up the exhaust?

Thanks for all the input!