Problems

[sbjalexis]

The boat was winterized last year and before started this season was tuned up and ran for a while to make sure no leaks in block. It had some previous leaks that were jb welded and had been holding fine. When ran with muffs no leaks and ran like a top. Took it to the lake this weekend ran good for about 10 minutes, gauges looked good (although they must not be right) and then we started to notice we were smelling oil, thought maybe that had been spilled and was burning off from tune up. Started to miss and then died, after it was not running we could hear under the seat it was sizzling, sounded like it was on fire. Was not thank god, will start and run now but we have not pushed it. Any thoughts? We also had the outdrive rebuilt last year as a note. By the way, this is a 79 ' 305 mercruiser.

 

[Bondo]

Re: Problems

Ayuh,.... Welcome Aboard,....
Check,+ replace the Impeller is the 1st thing to do in any Overheat situation...
Then diagnose from there...

 

[sbjalexis]

Re: Problems

ok, so we have had the front water pump off and it is good. the back impeller was changed last year when we had the outdrive rebuilt. with the muffs on it is shooting water out of the piece before the block, but nothing out of the house itself. does that mean it has to be the impeller in the outdrive?

 

[JustJason]

Re: Problems

It had some previous leaks that were jb welded

Normally I would ask if you checked the oil for water yet.

But in this case I think i'll ask how much water you have in the oil.

Welcome to iboats.

 

[sbjalexis]

Re: Problems

No water in the oil, checked that yesterday. Any thoughts?

 

[Chapmaster]

Re: Problems

This is just a thought. I had a similar situation just the other day. Started the boat for the first time this year. It started right up. I sat in the captain?s chair and watched all the gauges. Everything seemed fine until the temp gauge shoot way up. I shut down and looked around the engine compartment. I could not see anything and smelled fine. I took off the hose going to the thermostat housing and made sure that I had good water feed and I did. So I started back up and the temp gauge started moving back and fourth erratically. So long story short I either had an air pocket that got removed when I released the hose or my thermostat was stuck. Boat runs fine spent all day up in Canyon Lake TX.

 

[sbjalexis]

Re: Problems

When we ran the boat last night it is running good but the water coming in is good and cool and the water going out in the hoses into the motor is steaming hot. But the temp gauge says it is good. Also, no water in the oil at all. Also, their is no thermostat in this boat, is that normal?

 

[Chapmaster]

Re: Problems

The water coming out is not going to be cool by any means. And as far as I know I would think that you should have a thermostat. There should be there hoses attached to it. The hose coming from the impeller, the hose going to the block and the hose going out the manifold (exhaust). I could be wrong I am not a boat mechanic by any means and hopefully someone will chime in and so I am right or wrong. By the way you could check the threads and see if there is a manual for you.

 

[Chapmaster]

Re: Problems

http://forums.iboats.com/showthread.php?p=1693398#post 1693398

Try this service manual 3 I think.

 

[sbjalexis]

Re: Problems

Thanks for the response. We will check out the manuals and see what we can come up with. We ran it last night for well over an hour and no overheat at all. The block is defenitely leaking again but as far as the motor, running wonderfully and never offered to get hot at all. When we originally had the problem with the boat it was late at night and we could not really see what was going on so we cant say for sure that is overheated we can only say that when it died out in the middle of the lake that we heard sizzling and when we lifted the cover it was hot coming off there. Other than that we can not say for sure if it overheated or not since the gauges never said it was hot. Last night we took off the manifolds since a mechanic told us that since the pumps were working fine could be that the manifolds were clocked but they were fine as well. We dont know what to do other than put it back in the water and see what happens. Any more thoughts?

 

[Chapmaster]

Re: Problems

Since you pulled off the manifolds make sure to put new gaskets back on. Don't use the old ones. This will only make your troubleshoting worse. Also make sure that they are torqued to spec as well.