Miss Maggie is a 1976 58 LRC. She has Allison Model MH30 3:1 transmissions with oil coolers.
While checking the oil level for a recent trip I noticed the oil was dark in color on my starboard side. It does not smell unusual or "burnt". It does not have a gritty feel to it. Oil drive pressure is normal at about 150 psi.
I changed the oil and filter and traveled down to Venice, FL from homeport in Palmetto this weekend. It's about a 6 hour run down the GICW. Upon arriving in Venice I checked the transmission oil and again it had turned dark in color. I monitored transmission and transmission cooler temperatures on the way down and everything is normal at about 165 deg F.
Thoughts?
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Thread: Transmission Oil Dark Color
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05-29-2023 12:18 PM #1
Transmission Oil Dark Color
JD
1976 58' LRC Hull #311
"Miss Maggie"
Riviera Dunes, FL
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05-29-2023 01:10 PM #2Registered Member
- Join Date
- Jul 2016
- Posts
- 39
Re: Transmission Oil Dark Color
The rear seal on the engine is leaking engine oil into the transmission. I had the same problem years ago.
Caesar's Ghost
1980 58YF
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05-29-2023 01:34 PM #3
Re: Transmission Oil Dark Color
I was going to ask if oil levels were more in gearcase after running and if engine oil was less, would explain it
'88 55'C hull 394 BEATs Therapy
12-71 TA's ZF BW190 1.5:1 gears
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05-29-2023 01:59 PM #4
Re: Transmission Oil Dark Color
Had the same problem. Rear seal leak allowing engine oil into trans. Mechanic said it’s not a huge deal as it’s the same oil but something to be addressed in time. We did it right away. It’s a big job and costly because of the labor involved. He had to A frame the motor off the mounts to separate the housing.
Dave & Trina
Benedetto
1989 60MY HATDK310
Sturgeon Bay/Ft. Lauderdale
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Re: Transmission Oil Dark Color
Rear seal needs replacing. Sorry.
SEVEN
1979 53' MY Hull #563
Antioch, California
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05-30-2023 09:18 AM #6
Re: Transmission Oil Dark Color
Thanks for everyone's quick response! I also posted this on the LRC Club forum and got the same response.
I did check the engine and transmission levels after my 6-hour run and no significant difference in oil level in either engine or transmission.
I assume the boat has to be pulled to replace the seal as the prop shaft would have to be moved aft to separate transmission from engine?
For those that have had this done, can you provide a budgetary cost estimate or number of manhours it took to replace the seal?
Thanks!JD
1976 58' LRC Hull #311
"Miss Maggie"
Riviera Dunes, FL
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05-30-2023 10:17 AM #7
Re: Transmission Oil Dark Color
Ours was done in the water. The receipt is on the boat and I won't be there until next week but I'll look. It was done in Stuart Florida in 2019 so not sure how relevant it will be.
Dave & Trina
Benedetto
1989 60MY HATDK310
Sturgeon Bay/Ft. Lauderdale
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Re: Transmission Oil Dark Color
No you should be able to do it in place. Once the shaft is disconnected it can slide back a few inches.
Pascal
Miami, FL
1970 53 MY #325 Cummins 6CTAs
2014 26' gaff rigged sloop
2007 Sandbarhopper 13
12' Westphal Cat boat
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06-01-2023 11:41 AM #9
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06-01-2023 11:54 AM #10
Re: Transmission Oil Dark Color
I'll post the all the info I have once I get to her. Should be 7-8 June.
Dave & Trina
Benedetto
1989 60MY HATDK310
Sturgeon Bay/Ft. Lauderdale