Converting from 2:1 reduction

[Phil]

What is involved in changing a 2:1 reduction engine to a direct drive one? Example, I have 2 engines: one is a direct drive and the other has the reduction. I want to make the reduction engine the good one. The other one has a valve lifter problem.

[Don Moyer]

Phil,

By "making the reduction model the good one", I assume that you want to move the direct drive assembly over to the reduction gear model so you can use that engine as a direct drive in your boat.

You can pretty much follow the step-by-step instructions in our service and overhaul manual for removing the aft housing and reversing gear from the direct drive engine. You'll then remove the bell housing, the reduction gear and reversing gear as a unit from the reduction gear engine and install the direct drive assembly from the other engine.

Depending on your plans for the original direct drive engine, you could install the reduction gear and reversing gear as a unit just as it came out of the original reduction engine.

If both engines are sitting side by side and the aft housing bolts are not extremely rusty, this conversion could be done in as little as a couple hours.

Don

[Phil]

Thanks, Don,

I did go thru the manual, but the nomenclature confused me so I posted the question. I will also have the engines side by side for the work, too.

You are correct that the current reduction engine will be the final direct one. The current direct one has that sticking lifter I mentioned to you last year and I simply do not want to pull that engine apart when I have an excellent one on hand that I can transfer much of the new stuff to.

Phil (spring is here!)

[Phil]

Hi, Don,

I got the new engine yesterday and brought her home to strip the parts off prior to getting it sand blasted.

The ring attaching the reduction gear assembly to the trans is a larger diameter then the direct drive unit. I can't see how it will be possible to switch the units.

What am I missing? Or, is it all internal?

[Don Moyer]

Phil,

Not quite sure I understand your question, but after you remove the attaching ring (held on by six 1/4" Allen headed bolts), the back of the aft housing and oil pan will match up with the rear flanges of the direct drive engine. You have to move the direct drive reversing gear assembly over as well.

Don

[Phil]

Don,

That's what I wanted to know. I went back and examined the 2:1 more closely and see the attaching ring you mention. So the bolts there actually fasten the bell housing and the attaching ring to the aft end of the tranny?

I think I get it now. Thanks heaps...

Oh, interestingly, this A4 is a Stevedore model albeit with all the upgrade goodies typical of a well maintained engine: electric fuel pump, Indigo vapor system, Moyer FWC, electronic ignition, 100 amp alternator. It came out of a 1978 38' C&C.

[Don Moyer]

Phil,

The 1/4" Allen-headed bolts of which I spoke in my previous message secure the attaching ring to the aft housing, and the bell housing is mounted to the attaching ring with the six 9/16" hex-headed bolts you apparently already removed.

Don