Engine overheating

[Domsz06]

OK, So here's the scoop

SPBFan and I were working on my boat. He put one impeller in, engine over heated. We took it apart and see that it broke. Put a new pump and impeller in (the old one had some gouging) the boat starts heats up and the water starts to come out the exhaust (Thermostat opened right?) we turn it off. Then we turn it back on again and she won't put water out the back and gets hot.

We pull the thermostat and it does open.

2003 21IR 350/315hp.

anyone have any ideas? Could the water pump be bad? do you think there is piece of something stuck somewhere?

SPBfan will chime in with some other information too.

Thanks everyone!!!


Dom

[zad0030]

Sounds like it could be clogged somewhere or you had the fake lake hooked up or forgot to turn the hose on. Some silly mistake like that maybe?

[Domsz06]

the old impeller broke, but we found those pieces.

Fake a lake was hooked up, and we traced water through the entire boat, so it appears a pressure is an issue.....

How is there a wrong way to hook the fake a lake up?

[Domsz06]

and we didn't forget to turn the hose on, I'm not a COMPLETE idiot

[TeamAllen]

Not sure if this is your problem, but I replaced my circ pump a few years ago. It had rust stain leaking from the little weep hole on the bottom. I didn't have any overheating issues, just the leaking stain. It might be worth a look? Here is the thread I posted. Good luck!

http://tigeowners.com/forum/showthre...ight=circ+pump

[SPBFAN]

I traced the water in the boat all the way up to the main engine water pump. Then the water does not go beyond that point. The Sea Water pump and impeller is brand new and moving water. We are thinking that it could be something in the system that is clogged from it sitting almost two years.

Or the main water pump in bad and not pulling water from the lower level system and pumping in through the engine. But that does not make a whole lost of sense their is no noise in the pump like the pump plate has come of the shaft or anything and the pump is not leaking. My thought is that something is blocking the water from moving in the system like it should. Has anyone had this problem. The big thing we do not want to do is just start replacing parts.

[dogbert]

Did you say you replaced the water circulation pump, or just the impeller & housing?

I'd pull outbound hoses to the main water circulation pump...maybe you can see what's happening there. Also, check the hoses for blockage. Then try running a hose through the rest of the system. It sure sounds like the main circulation pump is toast. The only way to tell for sure is to take it off and inspect it.

[Paublo]

This is probably not your issue, but I'll share an problem we found the hard way. A number of years ago our houseboat on Powell had a problem on one engine (4 cyl.) that would overheat whenever it was going any faster than idle. Everything was checked and replaced and rechecked. Our mechanic tried everything and was pulling his hair out. Finally someone said pull off the exhaust manifold and check inside. Sure enough the inside was nearly plugged where water passages enter so it limited water circulation and what water could exit into the exhaust. Someone had used the boat in shallow water and sucked up silt which then coated and baked itself on the inside of the exhaust manifold. He slapped on a new one and problem solved. Who would have thought to check that? It just takes a restriction somewhere to cut flow. And when at low rpm there was enough circulation and less heat to reject, so no problem- just when under way at higher rpm.

[dogbert]

Good call, Paublo. Might want to check your muffler for blockage....maybe something crawled up in there during the 2 year hiatus? If he's got an FAE, then he doesn't have the flaps any more so it's entirely possible.

[Paublo]

Another- one of the many dumb things I've done was to replace the impeller of my daughter's older direct drive Nautique. Of course it is easier to take it off, replace impeller and put pump back on. We pull away from the dock and just as we leave the no-wake zone it overheats. I had rotated the pump and reversed hose connections, so no circulation. So it was a quick on the water change with my shirt in the intake hose as I rotated the pump and reconnect hoses- after we let it cool off enough to touch. We were lucky the impeller was still good. All she said was "thanks for the help, Dad." Just when they think you can do anything, you do a very human thing.

[SPBFAN]

Another- one of the many dumb things I've done was to replace the impeller of my daughter's older direct drive Nautique. Of course it is easier to take it off, replace impeller and put pump back on. We pull away from the dock and just as we leave the no-wake zone it overheats. I had rotated the pump and reversed hose connections, so no circulation. So it was a quick on the water change with my shirt in the intake hose as I rotated the pump and reconnect hoses- after we let it cool off enough to touch. We were lucky the impeller was still good. All she said was "thanks for the help, Dad." Just when they think you can do anything, you do a very human thing.

I thought of this being an issue and then I realized that the water would not be going through the system if this were the case. The hoses to the back of the pump are pretty much conformed to their position and I don't see that being the case but maybe possible.

I do like the idea of the blockage in the exhaust though that is a very real possibility. We need to check into that. This poor boat has sat for two years so things could have rusted up. The other thing that I am thinking is maybe a piece of junk broke loose and as DOMZ said plugged up the passage way at the back of the engine not allowing for enough flow.

[Yessup]

Ok, first I am now way any kind of mechanic, but I had similar proplem with my boat 3 years ago. My first time operating my boat after purchasing it. I hit a sand bar and sucked up some debris (sand & moss) My boat over heated imediately. We replaced the thermostat, and the boat continued to overheat. We, meaning my cousin and I -(Cuz is a mechanic) Checked the impeller, and impeller was fine, however when we removed the impeller for inspection we noticed some debris down in the pipe(?)in front of the transmission water intake(?) It was pieces of a shreded up old impleller, and sand, and moss. Maybe you've got some blockage in that area. Once we removed the blockage, the boat has been perfect. I hope this helps

[loudelectronics]

Have you cleaned the inline heat exchangers (HX). My HX were plugged up bad and caused mine to over heat.

[Tanner]

Sounds like paublo already got you on the coroded manifolds.

Don't be suprised to find a rats nest in there somewhere too, or even a nasty little spider nest. Those little suckers find ways to work themselves in their deep..... How they manage to work past the impeller, IDK... but I've seen weirder things.

[Domsz06]

well I don't have an FAE, so the laps are still on and were good and snug. We will start checking hoses tomorrow and see what we can find.... I think it's that or the water pump. I really think something just plugged it, because once the water was coming out of the back we just turned it off, we should have let it keep running for a bit to make sure everything was good and circulated out....

Keep everyone posted......