Running an inboard out of water - on blocks

OK, I am considering helping someone sell their 1988 33' cruiser which has been totally updated. He has one new and one rebuilt 454 engines. However, it seems when the mechanic installed them and tested the Velvet drives the drives didn't work. As best he can recall, actually, one didn't work at all and the other stopped working while testing. This was all done "on the hard".

Now, I suspect the mechanic was not very familiar with Inboard/velvet drives (nor am I AT ALL - but learning). I do not know if he took any precautions to provide water to the drives - I assume that's needed. Other bearings as well? He may well have fried something.

They did have cooling water to the engines and both engines are reported to run perfect. They have all new "trimmings" and cost a fortune to have done.

How does one run Inboard drives on land? Or isn't this done? I am proceeding under the assumption that the drives need to be rebuilt but not really sure. I will get a mechanic in to check it out, but wanted to understand this a bit better first.

Thanks.

Re: Running an inboard out of water - on blocks

Take off the hose at the water intake fitting inside, or where the hose meets the engine, (whichever is easier), and connect a garden hose there, turn on the water and run it at idle all you want

Re: Running an inboard out of water - on blocks

Velvet drives are like automatic transmissions in a car/truck in the sense that they basically work off the same principle.
They require the correct amount of the proper fluid to operate.
See ID tag on the drive for fluid type. Most are Dextron ATF.
Check fluid level and condition.

Water doesn't need to go through the drive for it to function. However water does need to circulate through the cooler.
Easy to make an inboard flusher using a household plunger and a hose fitting. The flush adapter is wedged under the boat around the raw water intake.

Re: Running an inboard out of water - on blocks

Velvet drives are tough little suckers. While that won't excuse stupidity or abuse, they are rebuildable and generally will last through several engines if fluids are properly maintained, with little more than a cleaning and a fresh set of seals.

What they don't like is heat-over 190 and it is time to flush and change fluid.

True inboards should not be put in gear out of the water as the drive shaft has packing that needs water for lubrication and the shaft strut has cutlass bearings that also use water for lubrication. While a second hose aimed at these parts will allow a brief engagement out of the water, it should only be at idle speed and by brief I mean under 30 seconds.

I would check the fluid in the one not working. A rebuild on one can be 1500-2000 bucks though I understand that they are easy to work on and if you are mechanically inclined you can do one for a few hundred in parts.

A slow day at the ramp is better than a hose!

Re: Running an inboard out of water - on blocks

OK, thanks guys. I think I sort of get it.

In this case I wonder if they ran the tranny dry and maybe the cutlass bearings referenced by J. Mark may have fried out? Would that cause the shaft to stop rotating? Interesting. How expensive is that to replace?

I wonder if these drives are both OK. I guess I need to get a better mechanic to find out. I may even drop it in the water so we can run it to test.

Re: Running an inboard out of water - on blocks

Cutlass bearings would make a lot of noise and would over time tear up the prop shaft but they wouldn't cause the drive to not work.

Did you check the fluid level in the drive? If the cooler were allowed to freeze, water/engine coolant could get into the drive and with the level high and the fluid contaminated it would not work (at least not properly)

Again these little units are tough buggers. Often even with contaminated fluid, you can repair the leak/source of contamination, flush the velvet drive and refill with the proper amount of fluid.-It might be shot, but there is a good chance it isn't.