Tx oil dark and smells burnt

[Fighterpilot]

Twin disc MG502. Tue. didn't want to go in reverse when leaving the dock. After a number of tries it worked. Got it to home dock and it wouldn't reverse. History--Recently slipped a time or two so drained the oil, it was still clear and no odor. Checked filter, put on pressure gage and no pressure when gear advanced to forward. Forum said check reverse also. Went back and checked both forward and reverse. It worked. Figure might have cleared a piece of trash. Made three, 6 hour each trips to the Gulf fishing, running 2300rpm 3208NA, than the reverse issue. Black, burnt smelling oil. It was low on oil. Changed oil, checked filter screen, and installed pressure gage. Now it goes into reverse. Pressure 300 psi which is at the bottom of listed range of 300-350psi.

Would the few tries to get it into reverse cause the oil to be dark and smell burnt, or is there something else going on during the 16 hours of run time since the fresh oil was put in? If not getting good circulation thru oil cooler would the temp. be enough to burn the oil? It is working now, should I just keep on running it or is there still a likely issue. If so what do I do? Is there anything else I can check with the tx. still in the boat?

 

[RickB]

Have you checked the oil screen for debris?

Try that first then be prepared for some internal work.

 

[Fighterpilot]

burnt oil

When we changed the oil we also pulled the screen. It was ok. Shall we just keep running it until it fails?

 

[RickB]

When we changed the oil we also pulled the screen. It was ok. Shall we just keep running it until it fails?

I wouldn't. There is a good chance that the repair might be twice as high after it destructs. Or, even worse, when it does it will do it when you are in a position that its failure will create a hazard to you or someone else.

 

[skipperdude]

FP I don't know what part of the country you are in but have you talked to Twin Disc about the problem?
I went through Mill Log. out of Seattle. Great company service tecs were right on with all the info I needed. Google them or check the twin disc dealer in your area.
better info than you will get on this or any forum.

Sd

 

[Chrisjs]

Are you leaking oil from the Twin Disc? We had a leaking seal (leaked clean oil) but when we pulled the MG5050 to repair the seal it turned out the seal had been damaged by debris from deteriorating clutch plates. Debris had also damaged the bearings. $3.5K later we have what is in effect a new transmission. Strange thing was there were no obvious symptoms before we took it apart, but by then the oil was discolored. I guess when they go, they go fast!!

 

[Forkliftt]

When we changed the oil we also pulled the screen. It was ok. Shall we just keep running it until it fails?

FP, burned oil =slipping clutch discs. Lots of things can cause this and low pressure is one of them. Can you locate the relief valve and remove it to clean? Another thought to me is that forward is pulling ok. The forward clutch pack should see lots more use than reverse, so to me it would probably be the pack to fail IF it was due to excessive wear. As Rick said, waiting on the repair could double the cost due to collateral damage. If you choose to continue to run it I would consider pulling an oil sample maybe after an hours running time and then every couple of hours afterwards to see if you show increasing metal in the samples. This could let you know if you dodged the bullet or possibly need to shut it down. Good luck!

 

[Fighterpilot]

Unless 2 or 3 attempts for reverse would do all that damage, I'm afraid forward has done it. Service here in the panhandle of Florida is terrible. The local twin disc rep. doesn't even have a mech on staff-two people operation. He has to call Hammond La. for any information or parts. 4 hours away. Jacksonville, 6 hours to the east is the next nearest twin disc shop. They had to get the last part I wanted out of Miami--12 hours away, so getting information or help on a twin disc is tough.

By the time we get the tx out and sent off somewhere for take apart and fix might as well swap for a rebuilt one I think. Will look for the relief valve and have checked the strainer when we changed the oil. Saved some of the oil so can get an analysis to compare to future looks. You would think with all the boating in Pensacola, Fl service would be more available.

 

[Forkliftt]

True. Who's the dealer in Hammond? We live near there. BTW, we have BW's and I'm told Zimmer Gears in Baton Rouge is the dealer for BW.