From Ronoldo...

[Marian Claire]

If you do decide to remove the reduction gear you could unhook the gear to prop shaft connection first. Then do a test run. If the problem persists at least you have eliminated the stuffing box/cutlass/junk on the prop possibilities. On the MC I can loosen the motor mounts and slide the A-4 forward enough to get the 2 to 1 bellhousing off. Only takes a couple of inches IIRC. Dan S/V Marian Claire

[Ronaldo]

Reversing gear

Thanks. Should have mentioned my boat is a California 33. I think I should have enough space to work on it without taking out the engine.

[hanleyclifford]

After re-reading this thread I still think something is wrong in the gear box. You should take off that cover plate and post some pictures of that band and the other components you can see.

[Mo]

Fwiw

As per Hanley's suggestion ...absolutely have a look at the gear box. Just to be sure, I'd recheck the compression with a good gauge. The thumb method of checking compression will give adequate results when done, however, it's not a guarantee. Summer of 2012 I worked on an engine and I did the compression check with my thumb and there was enough on each to pop my thumb off. We changed prop, carb, and fooled with the gearbox for days.

Finally used a compression gauge and ended up with a head removal and free the valves up. (I didn't do that, the guy had a mechanic come to the boat and do it)...He checked everything I did and it was good...so he went back to compression and used a gauge. 3 and 4 were not completely closing and resulting in loss of power...lesson learned on that and have since found a few more that were valve problems....idles fine, revs fine idling, bogs with poor performance and /or stalls when put in forward gear. Usually a bit better in reverse due to ratio.

[Ronaldo]

reversing gear

Hi all,

As requested, I attach 3 photos of the open gear box. Is there anything obvious missing?

I also took off the bell cover & attached reduction unit. There is obviously nothing wrong with it. The bearing seems fine. The mechanism seems so simply that it is difficult to see what could go wrong.

My intention is to start the engine without the reduction unit & check if the resistance in changing gears still persists. Is this a good idea?

regards

[Ronaldo]

Advances on reversing gear problem

Having taken off the reduction gear & uncoupled the shaft, I started the engine. The gears worked perfectly, but obviously with no load. The reduction gear itself is so simple that it it seems obvious that little could go wrong with it, & it does seem fine.
The shaft was free when we started this work but is now blocked temporarily.
But we are back to square one. What causes the stalling?
Could it be the lack of a gasket on the reduction gear cover? Or the outside bearing situated just before the prop?
Anyway we intend to put things back by stages & test at each stage.

PS I only attached 1 photo to my previous comment, not 3 as stated.

[Mo]

Hi,
Did you check engine compression with a guage yet?

[Dromo]

This might be too easy
Check the firing order you might have a few wires crossed
1,2,4,3
Rick

[sleonhard]

I like to start my engine periodically thru the winter and the last time I did when I put it in gear it stalled out a couple of times I just tried it now and all was good I figured the packing must have been frozen it was minus 30 something at the time and today we have plus temps I didnt have anywhere to go anyway surrounded in ice

[Ronaldo]

Reversing gear etc

The compression ratio is about 78 psi which is acceptable.

I think the source of the problem is the packing.
When we put everything back together, the gears worked fine. This may be because the shaft was moved to reinstall the reduction unit & may have loosened the packing.

However, I decided to replace the packing & the problem returned. I could barely get back to my mooring again. When I did, I loosened it but could not close it properly & although the engine got well into gear, water was sprayed into the engine department. Eventually I closed the leak but it started again every time I put it into gear. So I dare not venture out to sea yet.

At least the problem is identified, but the solution is pending.

The shaft has 1 inch diameter & enters a threaded tube which is attached to the "sock" ( I believe this is the correct term!). When I try to tighten the nut (2 inch diameter) which contains the packing, the whole tube moves so that I now cannot close it correctly. As a solution, I am thinking of taking out some of the packing to facilitate closure. I intend to block the tube temporarily with the counter nut.

Instructions on the packing material indicate 4 packing "rings" are required, each positioned separately. But my proposal will end up inserting only two & it may leak a little.

Is anyone familiar with this problem?

[hanleyclifford]

One thing we have not looked at yet is spark. The symptoms you mention could be caused by a spark that is strong enough to start the engine and run it without load but not strong enough to fire thru high combustion chamber pressure, ie compression. Test your spark while running in neutral and confirm that it is a big blue one that will jump 3/8" to 1/2". Do you have electronic ignition or points and condenser?

[Ronaldo]

Reversing gear etc

Thanks for your reply. Its a points & condenser set-up.
I'll check this when I return to the boat.

[hanleyclifford]

Thanks for your reply. Its a points & condenser set-up.
I'll check this when I return to the boat.

Confirm your dwell is within spec and check voltage at coil +. This should at the least eliminate ignition as the source of the problem.

[ndutton]

The compression ratio is about 78 psi which is acceptable.

I'd say barely acceptable

I think the source of the problem is the packing. . . . . I decided to replace the packing & the problem returned.

Are you sure you have the right size packing? As a test I'd try the next size smaller and only three rings. Also, some of the Goretex packing is oddly sized if that's what you used. I have a Catalina 30 pal who tried that stuff, wound up tossing it and going back to standard Teflon impregnated flax. His symptom was elevated stuffing box temperature underway (Universal M25XP 3 cylinder diesel w/ 1" shaft).