Leaking tranny seal..

[Gary Bergman]

My tranny seal's leakin'; I've tried a bottle or two of light duty conditioner, but still slinging fluid. Powerplant's a 70's 4-236 Perkins with a Velvet Drive tranny. Looks to me like there's a flange AFTER the seal, that would allow replacement inplace. Anyone with experience in this area? I hate like Bloody heck to shut the ole' girl down from having to pull the sucker....Dang! Lotsa typo's today; ruff seas...)

[ 10-12-2005, 09:12 PM: Message edited by: Gary Bergman ]

[sdowney717]

If it is the rear seal,
The output hub flange is held on with a large nut. The shaft is splined and matched to the output hub flange. If the propellor shaft can move far enough back to get in a large socket wrench then perhaps it can be done. You will have to hold the output hub flange steady while turning the nut.
And you may need to rig a puller to separate the hub flange from the shaft.

[Old Bingey]

Sometimes running the propeller shaft out of line for a long time will wear out the splines on the output flange and even wear the splines on the output shaft of the transmission allowing the flange hub to wobble and defeat the seal. That's a mess. One way to diagnose it is to pry between the flange and the back of the transmission to see if you can make it wiggle. That's the first thing I do when I come across a used Velvet Drive or Paragon transmission I think I might want to add to my collection. It is a common problem.

Good luck.

[willmarsh3]

On a Volvo Penta there are paper gaskets used between the transmission and the engine. Are you talking about rotating shaft seals instead? These gaskets eventually deteriorate and leak oil into the drip pan.

Will.

[Gary Bergman]

It's the rear seal, output shaft. No problems with 'wobble', or anything else, just some wear on the top side of the seal, or so it seems. During the Tallships Challenge 2005 we were in some rather heavy following seas, with the rpm's quite high. After some packing gland work this summer, I know the shaft will travel reaward; dunno how far tho'.So, a recap..you're saying that behind the flange, held on by mebbee six bolts, there's a shaft nut??.Does the seal itself need a puller?? hard place to work, I'll hafta pull a generator just to get close.

[Gary E]

If it's your output flange seal that is leaking
look here to see the cross section..

http://www.tadiesels.com/borg_warner-inline.html

edit to add
I dont think that what you call high rpm has any effect on the seal, your engine would have to rev to blowup speed and be out of balance for that to happen and it wont. What often does wear seals is dirty oil and shaft misalignment. Do you pull the boat out of the water for the winter?... if you do do you separate the flanges so the transmission output bearing is not loaded? When you put the boat in the water do you re align the motor and trans flange to the flange on the shaft using feeler gages?

edit...
I just looked at that cross section and see that the nut that holds the flange on is also the bearing adjusting nut, so it should probably have a cotter pin holding it and when putting it back together be carefull to not have the brg to tight or too loose.

[ 10-13-2005, 11:53 AM: Message edited by: Gary E ]

[Invader]

Garry

From my experience you can get at and replace the rear seal like sdowney717 states. If you have the room to slip the shaft back and clear. If you have that room it should also be possable to remove the trans if need.

I also suggest that you try to find out why the seal has started to leak. It can be a sign of problems that will bite you down the road if not corrected.

From past experience with these its usualy from the likes of bad or loose machinery mounts, poor engine alinement, bad bearings , broken bolt etc. So I am making a bit of an extension to the point Old Bingey makes.

Could be just an old seal thats been soaked in the bilge to many times but poke around just in case.

My two cents for what its worth.

Willy
Invader no 1
39 Kishi Conversion

[Gary E]

From my experience you can get at and replace the rear seal like sdowney717 states. If you have the room to slip the shaft back and clear. If you have that room it should also be possable to remove the trans if need.
Agree

[Old Bingey]

The output coupling flange and the part the seal ride on are one piece. There is a great, big nut recessed into the flange that you can't see without separating the two coupling faces and pulling the shaft rearward. It takes a long extension to loosen that nut and the flange tries to turn. You can hold it by putting two of the coupling bolts back in so you can pry with a bar but it is aggravating and difficult. When you get the nut off, if there is wear in the splines like I was talking about in my previous post, the flange will pull out by hand but if all is well, you'll probably have to pull it. Once that is out, the seal is easy money.

Good luck.

[Gary Bergman]

Well, looks as tho' I'll be able to replace it, now to find where to order one or two up. As far as 'why', the seal is original, was hauled every unfriendly winter in Canada,been trailed at least a dozen times, has seen much water in her lifetime,endless charter work from Florida to Canada in her younger years. The leakage seems to be a half quart or so every 75-100 nm's at around 5 and a half knots. Shaft is good, and I've slid it back for access to get a puller behind the prop before; never went farther, but it sounds like a few inches should do

[Old Bingey]

I have always been able to get a seal through Bearings and Drives or some other such industrial outfit instead of Borg Warner. Another thing to look for when you get that hub off there is the surface where the seal rides. A lot of the time rust has pitted it and the seal itself has eaten a groove into it. To keep from having to buy a new hub from BW, there is a very thin stainless steel collar that will cure that but it enlarges the diameter of the hub slightly so you will need for the seal to fit that. This is a common problem in all sorts of machinery so Bearings and Drives has access to all sorts of seals and sleeves.

Another thing: If you don't have room for a puller behind the flange, it is possible to start the separation with a wood wedge driven between the forward part of the flange and the back of the reduction gear case. It isn't like trying to pull a bearing. All you have to do is break the crud in the splines and get the seal lip out of the groove it has cut in the hub. If you can get it to move, it'll slide right off.

Be sure to check for looseness in the splines when you get the shaft couplings separated. It is possible that the shaft is out of line enough so that it is binding enough to keep you from wiggling the output flange when it is hooked up. If there is much wiggle back there, a new seal won't fix it. I have heard of people glueing the old worn hub to the old worn splines (which are integral with the big reduction gear!) with J. B. Weld epoxy but you have to make sure you get it straight before the epoxy sets or you will build in a wiggle. I guess you could run it with a dial indicator on the flange and tap it until it ran true. I wouldn't know. I don't do crap like that, myself.

Good luck