OMC Cobra impellar problems

[raytom]

Ok Guys, Last year I put the boat away with a impeller problem. I think I have a blockage. I burned a impeller last so I replaced it and took the boat out and burned another. The thing is that when I took the impeller out it had fins that were facing the wrong way. I know I put it in with them all in the right direction. I did run it on muffs at home and it worked fine. I checked it out after I ran it to see if there were any fins pointing in the wrong direction. There were none. Then I took the boat out and ran it at a good speed for about 20 mins and started to over heat. Whan I took it apart some fins on the impellar were in the wrong direction. Would a blockage couse pressure to build and move the fins or is it some thing eles. What common places may block up in a 88 4.3 omc cobra. Or is this not even a blockage problem?
Any help is appreciated, Ray

 

[Rob454]

Re: OMC Cobra impellar problems

Mine is like that also. a coupel of the fins face the wrong way but as soon as the motor turns they spin the right way. When your eburning out the inpeller what does it look like. is the rubber melted or broken in chunks?
I woudl look at a possible stuck thermostat since youre overheating within 20 minutes
Rob

 

[raytom]

Re: OMC Cobra impellar problems

I did put a new themostat in at the start of last year. The impeller is melting down and shifting the steal liner. it was like 20 mins at like 3500 to 4000. also ideling out of no wake zone.

 

[raytom]

Re: OMC Cobra impellar problems

Is there any thing that could get blocked or restricted in the out drive? I am going to get the risers off today and try to clean them out.