Prop not spinning/Heat gauge rising

[MauiDreamz]

I have a Sea Ray 250 1987 With a 260 alpha Ray 1 V8. I replaced the 3 fin prop with a 4, everything tight and secure, enjoyed about 3 miles of crusing at optimum performance, when my prop quit spinning and the heat gauge rose. I have purchased a new impeller kit with gaskets and am going to put this on to solve the heat problem, but why would the prop quit? I am thinking I need a new coupler, but am unsure. Can anyone give me goood advice on this? In "Drive", the prop spins clockwise, but no counter clockwise, in neutral, it spins both ways and reverse it spins only counter clockwise.....Can anyone direct me to solution or to a web page which shows the parts and numbered with names so I can visualize the procedure with names of the parts? I believe it simply needs a new impeller and coupler... any thoughts are appreciated....

 

[QC]

Re: Prop not spinning/Heat gauge rising

Welcome aboard Maui guy!

crusing at optimum performance, when my prop quit spinning and the heat gauge rose.

I moved this over to the Mercruiser section as this does not sound like a prop issue. If it truly stopped spinning AND the overheat coincided exactly with that then I'm thinking drive issue. Why do you mention coupler?

 

[Don S]

Re: Prop not spinning/Heat gauge rising

If your couple splines are spun out, the shaft going into the outdrive from the back of the engine will not turn. Since the water pump is in the outdrive, it will not be pumping water.
You should see a bunch of metal shavings around the coupler and shaft.

 

[Aatcman]

Re: Prop not spinning/Heat gauge rising

Could be a couple of things....

Your description of the lower unit sounds like a properly working lower unit..

Sounds to me like either your coupler broke, your ujoints broke, or one of the gears or shafts in the upper housing broke.

This would remove power from both the prop and the impellar. Fix the problem and both propulsion and cooling will come back.

Did you hear a loud pop, clunk, or slam, or anything like that?
If not, then I'd say the coupler is the first possibility to investigate......

 

[MauiDreamz]

Re: Prop not spinning/Heat gauge rising

Thanks everyone for your input. Turns out the impeller was fine, but when I ran aground prior and lost my prop, the lower unit was so packed full of dirt and mud that the water flow was halted. So, I have a new impeller now anyway. The upper pinion gears were the culprit for the non spinning prop. Soooo.... Bust out another thousand!!! Thank you for all of your insights....