350 MAG Serpentine Belt Help

[Soda Bay Gal]

Hi, longtime follower of the board, first time posting. We have a 350 MAG MX 6.2L MPI SKI that has never experienced an issue. Winterized end of last summer and installed a new impeller and serpentine belt last June. Recently launched the boat and experienced a very loud squealing sound. The belt is not catching on the seawater pump. Pulled the pump, impeller looks fine and the pump is in good shape. This engine is not impacted by the service bulletin with the shredding serpentine belt. Can anyone tell me what I other areas I should be checking. Also, I have been trying to educate myself as much as possible and am wondering if the impeller is slightly curved would that be considered ?taking a set?? Would this cause the belt problem? Appreciate any assistance as I am just a mom trying to get the boat working for the kids.

 

[Bondo]

Re: 350 MAG Serpentine Belt Help

Hi, longtime follower of the board, first time posting. We have a 350 MAG MX 6.2L MPI SKI that has never experienced an issue. Winterized end of last summer and installed a new impeller and serpentine belt last June. Recently launched the boat and experienced a very loud squealing sound. The belt is not catching on the seawater pump. Pulled the pump, impeller looks fine and the pump is in good shape. This engine is not impacted by the service bulletin with the shredding serpentine belt. Can anyone tell me what I other areas I should be checking. Also, I have been trying to educate myself as much as possible and am wondering if the impeller is slightly curved would that be considered “taking a set”? Would this cause the belt problem? Appreciate any assistance as I am just a mom trying to get the boat working for the kids.

Ayuh,... Welcome Aboard,... Ya, that would be takin' a Set, 'n it needs replacin',...

With the belt off the pump, does the pump turn over with only abit of resistance,..??

You say the belt ain't "Catchin' " on the pump,... Ya mean the belts turnin', but the pulley on the pump Ain't,..??

That is tellin' Me, the pumps turnin' too Hard,...

 

[Don S]

Re: 350 MAG Serpentine Belt Help

Is the belt tight? What is your engine serial number. You are calling it both a 350 and 6.2L one of them is wrong.

 

[Soda Bay Gal]

Re: 350 MAG Serpentine Belt Help

Thanks so much for the quick responses. To answer your follow-up questions.
Bond-o The water pump pulley did not turn as easily as the other pulleys however I assumed this was due to impeller resistance. With the pump off the motor and the impeller removed the pulley turns easily. Second question, yes the belt turns but the pump pulley does not.

Don S - The serial number is OM392735. I pulled the title of the motor from the Mercruiser parts website when I punched in my serial number.

Appreciate your help; I see how much I have to learn.

 

[Don S]

Re: 350 MAG Serpentine Belt Help

Ok, you have a 350, not a 6.2. That is what I was looking for.

Is your belt on like the picture below, and is it tight?

 

[Soda Bay Gal]

Re: 350 MAG Serpentine Belt Help

Thanks Don - Yes I believe the belt was on correctly, exactly like the manual and diagram above. Thanks for educating me on the motor size. I will get a new impeller and try that. Do you think I should also get a new belt?

 

[Don S]

Re: 350 MAG Serpentine Belt Help

Thanks Don - Yes I believe the belt was on correctly, exactly like the manual and diagram above. Thanks for educating me on the motor size. I will get a new impeller and try that. Do you think I should also get a new belt?

With the pump off and the impeller out of it, make sure the bearings are absolutely smooth. If they have rust on them and some rough spots, it could lock up and stop the pulley.

Is the belt ok? I have no clue, I can't inspect it all the way around from here.

You never did answer the question if the belt was tight or not.

 

[Soda Bay Gal]

Re: 350 MAG Serpentine Belt Help

Thank you again for your assistance. The belt looked fine (sorry I did not answer that part). We will be heading to the lake
on Wednesday and will check the items you suggested.