Vibration in Alpha drive

[loppster]

A little background....I was out on the lake a few weeks ago and the engine(350 Merc 260hp) started missing. Had to remove the distributor to get the cap off. A couple of the screws were rusted on. Replaced the cap, rotor and the ignition sensor. Reset the timing and the engine runs fine.

Here's the problem.... When setting the timing, the muffs came off of the drive. The temp went up and we shut the engine down. Placed the muffs back on and restarted, and the engine temp came down to normal. The problem is I now feel a vibration from the lower unit. Could the vibration be from "frying" the impellor or water pump? Or could it be from something else?

 

[DHPMARINE]

Re: Vibration in Alpha drive

If it ran hot enough,long enough,you might have melted the prop hub bushing,causing an imbalance in the prop. I think it was older Johnson V6 out boards that had this problem.

DHP

 

[loppster]

Re: Vibration in Alpha drive

Thanks DHP!

One thing I did not mention in my post was that the vibration went away when I got over 2000 rpm.

I'll try an older prop this weekend.

 

[vipzach]

Re: Vibration in Alpha drive

It only takes a few seconds of running dry to ruin an impellar. The impellar needs to be replaced. I have seen on here where guys will run a coat hanger through the muffs and the water intake to prevent it from slipping off!!