Transmission Issue?

[bassviking]

Engine is a Volvo MD2B with a type MS reverse gear.

The issue is that after motoring for say an hour or so when I take the transmission out of gear it will not go back into forward. It will go into reverse. I've found that if I shut the engine down for a little while (today I did 10 minutes usually I let it sit overnight) and then restart the transmission will go back into forward like it was never an issue.
This is usually only an issue when I'm trying to dock the boat and even then its not much of an issue as I usually take my time and go dead slow being that when I dock as I'm usually singlehanding and nobody is around to catch a line. However, I'm not happy with the issue and would like to be able to resolve it if possible.

I wonder is the transmission is overheating or something like that?

Transmission oil was changed a month or so ago.

[Rockter]

bass :

If the transmission were overheating, you would detect it. I have the same gearbox, and on a long run you can't bear your hand on it, but it won't fry it.

But do this. It should help. :

Disconnect the gearshift cable from the gearshift quadrant on the gearbox. Now you have manual control at the gearbox without having to factor in cable adjustment or cable friction. With the cable disconnected, you will find it pretty easy to change gear manually.... just push the quadrant back and forth a few times for fwd, neutral and reverse. If you have difficulty, try turning the propshaft a wee bit.

Now, put your gearbox into gear by manually turning the gearbox quadrant and run you motor and gearbox up to operating temperature.

Do you have the same problem with the cable disconnected?

If the problem is gone, you have a cable adjustment or cable friction problem (easy to fix).

If the problem is still there (and I doubt it), then you have a gearbox problem (not so easy to fix).

On a separate note : keep an eye on that gearbox seal back there. Mine blew back in 1997, and drained the box. I almost lost it. I noticed a "clunk" when changing gear with the motor hot, and when I checked the box there was no oil in there. The spinning shaft had slung it in a line (clearly visible) all over the engine room walls. Get a wee mirror, and when the 'box is turning, hold it so that you can see the lowest part of the seal. Use a flashlight to help you. No loose clothing or rags around! Be careful!

It is a good gearbox : terribly-pricey spare parts though, but, running in ideal oil-bath conditions, it does not often give trouble if treated well.

Let us know how you get on.


Rockter.

[erps]

You really have to watch the oil level with that particular transmission. Our boat has gone through two of them. Once with the previous owner and once on my dime. When it failed with me, it wouldn't come out of forward and split the case open. I check the oil every ten hours now.

[simpsoned]

I have an MD7 that had similar issues...agree, check the oil and check the cable...I found my cable was stretching as the engine heated up and the 1/4 inch or so difference was enough to play h___ with the tranny...

[Capt Len]

Not an md comment, but one for Borg Warner Velvet Drive owners. If oil is low. the disks in forward wont release when hot and you go into reverse, Can't be in both gears at the same time so engine stops and cannot turn over until things cool off.The disks and bands relax and all is well again but checking the oil every time can save your butt.

[colinflteng]

Just confirm that you are using engine oil in the transmission 15W 40 wight does any one have a manual for the M2SB Gear box