Borg Warner trans leak
- bud37
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Re: Borg Warner trans leak
As I said earlier, it appears that this shaft seal leak has been an ongoing problem with these drives. They had a repair way back when with an improved lip seal. My trans came from the factory with mobil fluid 424 as the fill....it has seal conditioners in it and is a heavier hydraulic fluid for use in shared sump cases. When it got changed to the red auto trans fluid (poorly thought thru by Marina staff and BW ) we all know and love, they both leaked like a sieve. The fix at that point was to flush and return to the 424 which by the way stopped the leakage on the one trans and slowed the other to almost none ( it does it doesn't ). As has been said these seals are very touchy in regards to shaft alignment, but really on a fibreglass hull that is always moving somewhat anyway. Once out, the seal change is quick and cheap, it is just the removal and reinstall where the problem lies and all the attendant problems that come with that.
In my considered opinion there should be some help from the original makers considering they have known about this for quite some time. If the OEM did not require such a small package footprint it would be easier to maintain.
A bit long winded and no real consolation but never the less a little background.
In my considered opinion there should be some help from the original makers considering they have known about this for quite some time. If the OEM did not require such a small package footprint it would be easier to maintain.
A bit long winded and no real consolation but never the less a little background.
FWIW.....The above is just my opinion.
- Randazj
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Re: Borg Warner trans leak
Bud37 Thanks for the post. I do agree with you about the seal issue. Borg has really done us all wrong with this transmission. The tolerances they call out for shaft alignment are .003 or .006 of an inch. Less then a sheet of paper. My issue I found as well that concerns me is when I rotate the shaft by hand on the P side it spins freely with some expected resistance in neutral. The SB side you need to practically put a wrench in the coupler shaft bolt. I am regardless going to get both engines aligned. A guy who has much experience with this told me to grab on to the coupler once it’s out of the boat and shake it, if it’s tight then the gears and splines in the drive section may be ok but if it chunks, then there is a problem. The huge issue is Borg has topped producing many of the parts or has been significantly delayed on fulfilling orders. The other problem is the ridiculous amount of money they charge for the parts, and the final issue is the piss poor design. The intermediary shaft bearings and gears should have been press fit and not held on the way they are. With how much they charge for a trans, we should not expect 1970’s design. I know I am ranting here but after talking to several qualified shops I here nothing but bad news. I will keep the forum posted on the progress. Engine gets pulled Sept 25th week and then we will learn more from the certified velvet drive trans shop on what the damage may be. All of them seem to fill with trans fluid, but I like the idea of the thicker fluid. Some trans run 30wt oil on diesels with less rpms white much less leaks. Maybe I can fill them with that after rebuild
- bud37
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Re: Borg Warner trans leak
Part of the reason could be the way they reverse the direction in the transfer case.....one has gears to reverse, the other uses a chain to keep the rotation the same, can't remember which side is which right now. If you check the different viscosities from pink trans fluid to some of the other acceptable hydraulic fluids there is quite the difference.
Good luck with your upcoming job....
FWIW.....The above is just my opinion.
- Randazj
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Re: Borg Warner trans leak
650 guy sometimes the trans will not leak, especially if it is shaft seal related, until the transmission is turning. Make sure you check it after you have been out for a cruise. My V-drive on the 350 Mariner only leaked while underway. If I run the engine at 1500rpm I found no leak on dipstick, hydraulic hose, or the shifter o-ring which is another common leak spot. Unfortunately in my case I found it is likely the front output shaft seal.
- Capn Crunch
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Re: Borg Warner trans leak
I've read this thread with more than just a little dread - and I don't want to hijack it - but feel compelled to ask regarding V-drives as we are in the process of purchasing a 310 Santego w/them. Are all inboards from the same supplier or did Carver use other makes? If so, is there a simple way if divining make/model of said drives? Does that even matter or are they all similarly flawed?
Sorry, anxiety went from really low to ultra high as I read thru (especially the part regarding the high cost of the fixes/replacements for these units) this thread - making me wonder how much I really like this vessel being looked at for us as I type.
Sorry, anxiety went from really low to ultra high as I read thru (especially the part regarding the high cost of the fixes/replacements for these units) this thread - making me wonder how much I really like this vessel being looked at for us as I type.
- bud37
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Re: Borg Warner trans leak
It should be noted that the drives being discussed here are the shared sump attached to the engine v drives. I believe on the Santegos, at least the bigger ones I am familiar with there is installed the RV drives....which are simple remote v drives.....the engine and trans are connected as normal, then there is a shaft connecting the trans to the V drive itself which is nothing more than a reversing gear case. Those are pretty much bullet proof in my opinion.
It is quite easy to tell the difference when seen in the boat.
It is quite easy to tell the difference when seen in the boat.
FWIW.....The above is just my opinion.
- Capn Crunch
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Re: Borg Warner trans leak
having always owned stern drives I wouldn't know a V-drive if it bit me... any chance you can point me to some pics somewhere showing the difference? The boat we're looking at is a 310... the occasions I've had to look in the bilge appeared to have a gear box underneath the motor, not at either end?
- bud37
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Re: Borg Warner trans leak
Sorry I am not familiar with the 310 model in any way.......I suggest you google borg warner v drive pics, as there is a lot of info and explanations that are much better than anything I can come up with. Also you would really have to know the specific engine drive combo in the boat you are considering as there are different oem providers which are different to the specific discussion here. Engines being black, red or blue.
Seaboard marine has some info and various examples......https://www.sbmar.com/articles/all-abou ... -v-drives/
I will add that in my opinion, many of these problems can be avoided with proper installation and correct maintenance, as in regular engine/prop shaft alignments.
Seaboard marine has some info and various examples......https://www.sbmar.com/articles/all-abou ... -v-drives/
I will add that in my opinion, many of these problems can be avoided with proper installation and correct maintenance, as in regular engine/prop shaft alignments.
FWIW.....The above is just my opinion.
- Capn Crunch
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Re: Borg Warner trans leak
Okay, thanks very much for the input - and willingness to reply... I've found this forum more responsive than some in no small part due to helpfulness from individuals like yourself.
I know the engines are Crusader (blue) but I think while the boat is @ the shop I'm going to see if I can get some pics of running gear to compare with the link you provided!
Mark
I know the engines are Crusader (blue) but I think while the boat is @ the shop I'm going to see if I can get some pics of running gear to compare with the link you provided!
Mark
- Capn Crunch
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- Posts: 72
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Re: Borg Warner trans leak
Well after a visit to the shop the boats at I discovered they are Hurth 630A? trans and drive units? mated to Crusader 350xl efi power plants. Hopefully those fit the "bulletproof" category 
