Addressing Overheating Issue

[scarpint]

In another thread I reference a couple of issues with my '88 Sea-Ray Sorrento (21' with 5.7 carburated motor and Alpha 1 outdrive) and I'm gonna start different threads for each.

Seems like the motor is running hotter than what has been normal for this unit. Typically about 145 no matter what I'm doing. Boat has not been in the water for last two years, but has been winterized appropriately the whole time.

I am replacing impeller, and want to also do the thermostat since I have no idea if/when it's ever been changed. I have not done this before and the questions I have are one, is this the thermostat in the upper portion of the picture and two, if it is, how difficult is it to remove because I'm leary of trying to get this out (if it indeed comes out) because it seem stuck in there pretty good.



Also, when I took this Unit out, I noted this casing around this sensor (I'm assuming it's a temp sensor of some sort) was cracked and just fell off. Does anyone know what this material is?



The springs and little plastic balls seem to function properly, but I am curious how these work in relation to the water flow.

Thank much for considering

 

[ktbarrentine]

Re: Addressing Overheating Issue

Yes...that is the t-stat.... and it looks identical (condition) to the one I recently replaced in my engine. Looks like it hadnt been touched in the twenty two years since the engine was new. Took alot of finessing to get it out. Had to press it out (you can tap it out with the rigth sized socket or other device). It actually tested sat, but since they are fairly cheap, I put a new one in anyway. Cleaned up the entire housing, and of course, new gaskets. A beautiful thing. Therapeutic. 145 sounds great.

 

[scarpint]

Re: Addressing Overheating Issue

Thanks...So, does it come out towards the camera (the top of the housing)and should I "attack'' it from behind with a socket around it's outside frame? Would a little PB Blaster be of any help? I'm replacing no matter what.

Thanks again!

 

[ktbarrentine]

Re: Addressing Overheating Issue

Yes...comes out upwards...Attack from underneath... I actually used kroil and let it soak, then worked it back and forth til it popped out. expect to trash it. get a new one. As I remember, there is also a brass sleeve above the t-stat.... looks like yours is out, or you didnt have one (Piece 10 on the following link: http://www.crowleymarine.com/mercury-outboard/parts/1014_220.cfm ). That was the piece that gave me the most trouble. Once the sleeve was out, the t-stat came out pretty easy.

 

[Silly Seville]

Re: Addressing Overheating Issue

That broken piece is definitely the remnants of your temperature sending unit. You need a new one. Your engine uses the 140-142 degree version thermostat, so replace it, and you're good to go. Those plastic balls regulate and equalize the water entering the risers to give the water more time to absorb heat before passing thru the exhaust system. They are not adjusted as part of regular maintenance...only if replaced

 

[scarpint]

Re: Addressing Overheating Issue

Thanks for the responses. I got everything back together tonight and started the boat in the driveway. Held between 145 and 160 on the temp and neither riser was too hot to touch, unlike earlier this week. We'll put it in the water and see how it does, but I'm thinking I may be good to go.

I hope everyone realizes what a valuable forum this is!