How can I check the drive clutch with out tearing things down

[John Vinzant]

Have a 1980 OMC 3.0 with 400 Stringer outdrive. At higher rpms, it seem like the prop is cavatating, the cavation plate is below the bottom of the transsom. So I was hoping that it was not the clutch pack. Is there a way to check the clutch pack without taking everything apart?

 

[Bridar]

Re: How can I check the drive clutch with out tearing things down

If your clutch pack is worn enough to be slipping or making that kind of noise, you should see 'signs of wear' in the oil.

 

[Howard Sterndrive]

Re: How can I check the drive clutch with out tearing things down

there are no clutch packs transmitting power like an automatic transmission. The only clutch involved in propulsion is a metal to metal "dog" type clutch in the lower unit. It doesn't "slip" the way you describe, it releases with a loud clunk and bang if worn... feels like you hit an underwater log.
Try another prop, the rubber friction hub may be rotting/slipping.


There is one friction clutch in your drive system, but it's for tilt, not propulsion.

 

[John Vinzant]

Re: How can I check the drive clutch with out tearing things down

Will check prop tonight, there is no banging or thud when this happens, so it could be the prop. Will advise on what I find.

 

[John Vinzant]

Re: How can I check the drive clutch with out tearing things down

Mr. Howard, you are correct, found that the prop was starting to spin on the hub. Found that the center section can be knocked out and replaced. Did this and it was half of the cost of a new prop. May go out tomorrow and see how it does.....