Went out today and getting up on plane I had a lot of slippage. I thought at first I had just gotten in some weeds and fouled the prop. Stopped, put in reverse to clear it and tried planning again. Same thing, started to come up but again way over revved and no go. Limped back home, inspected prop and prop is perfect with a solid hub.

Drive is a Bravo XR, rebuilt last year by All American Drive Service. It shifts in and out of gear fine. I couldn't detect any burned rubber smell. I am thinking coupler or maybe a cone clutch but don't know how to check either or maybe it is something else?

Help,

Padraig

It's either in gear or its not. A drive will not "slip" once in gear. It sounds like a prop hub (which you said is fine) or coupler.
You can visually inspect the rubber on the coupler at the rear of the engine where the drive input shaft goes in.
If the rubber looks good, you need to pull the drive to inspect the splines on the coupler.

Which way is your prop rotation?

If your running bilge blowers you may not smell the burnt rubber, but either way I'm thinking coupler

Took a flashlight into the bilge and as far as I could tell the coupler "looked ok, didn't see any chunks of rubber in bilge. Prop rotation is left, 5 blade hydromotive. Had it for a number of years, works good and no dings nicks etc.

Padraig

I had the same thing happen to me a few years back. Stopped to tow a wave runner in and sucked the tow rope in my prop at idle (long story with a stupid person in tow-never again) and stalled the engine as i was putting it in neutral. After i got the rope out of prop. I was heading home and said something isn't right. Speed was down 10-15mph from my normal cruise speed. I thought I damaged the drive and went to a ramp that was next to me. Towed the boat home and checked everything. Marked coupler, changed prop and went out. Everything normal. Put original prop back on and went out again. Back to normal. Later on I found out the marina I towed the wave runner to has bad eel grass buildup. I think the prop was just entangled in it.

If you found nothing I would go run it again and see.

I had a situation where my l/h drive broke loose while coming on plane also broke loose while running hard in rough water, pulled it off, took it apart and all I found was the upper collar and the 2 keepers that go into the clutch shaft were grooved and shiny( I imagine the collar was spinning on the keepers and not turning the clutch shaft), I replaced the keepers and the collar and it worked fine, it was by far the cheapest drive repair I ever did.

Took the VR 1 out yesterday and loaded it on trailer. Everything looks good but again could not get up on plane, starts slipping badly at about 2,000 rpm. Bringing up to Grand Island NY to Excel Marine this morning. Will let everyone one know what we find although I am not sure how quick they can get to it.

Padraig

Well got the VR 1 back yesterday. Can not say enough good about Excel Marine. he pulled the drive, visually inspected coupler and put long shaft on it with a breaker bar and tried to move it. All looked good. He did find the shift cables were out of adjustment and called to ask if I ever experienced a delay and a clunk while shifting? I told him occasionally but after it did it ran fine. I did remember that it had done that the day it started slipping. Paul at Excel thought that that could be the problem. To be sure he checked the cone clutch and gears...All were fine. He did flip the cone clutch. While it was not the problem he replaced the yoke that had some wear and flipped the celery stick that was installed backwards for a XR drive. Brought it home, launched, and it planes fine and runs great! Thankfully my summer not over.

Thanks for the help and thoughts,

Padraig