Transmission Problems and Probable DIY Overhaul

1975 SN, 351W, Velvet Drive 71C Transmission

One day last week at the end of a few hours on the water, forward started slipping. Drove the boat about 10 minutes to the lift, and on arrival there was no forward remaining. It might have had some reverse, but I didn't do any experiments. I checked the level and there was very little transmission fluid -- in the tranny, that is. There was a considerable amount in the bilge.

Today I went to see if I could find the leak. I wiped the transmission clean and re-filled it with fluid. Then I slowly putted around while re-gapping the points and re-timing the ignition. The tranny shifted as it always has; smooth, albeit a little noisy. Total of maybe 5 minutes in gear.

When I checked for leaks, I could tell the fluid was coming from the front of the transmission near the bellhousing. The front bottom part of the transmission had fresh fluid on it (I had wiped everything down beforehand). Not a whole lot, but enough that it was clear where it was coming from.

I'm considering three options: replace the front seal and pump gasket and run it until gas hits $100/gallon, replace the front seal & gasket but overhaul the transmission at the end of the summer (November around here), or rebuild now. Since I have to pull the transmission with any of those options, I'm leaning towards rebuilding it now.

So I have decent wrench skills, but I've never overhauled a transmission. I have Borg Warner VD manual and overhaul looks like a fairly simple affair. My plan is to install a rebuild kit (gaskets, seals & O-rings, and clutch plates) and perhaps replace the annular bearing at the rear, and whatever else I find in there. New damper too.

Anyone have any life-lessons, tricks or tips, or BTDT they want to share? Pics would be great. Especially of how to use the bottle jacks to lift the engine a little without puncturing the fiberglass floor . . .

Any help or advice would be appreciated.

Shawn,
I happen to agree with Tim here especially the reason for it blowing the front seal. Others have been through this before and found out the hard way that just sticking rebuild parts in it doesn't cure the problem. The seal will blow again. Eric knows how to handle internal clearances that are most likely out of spec. The V/D manual doesn't get into that. Send it off to Eric!

The bottle jacks under the exhaust manifolds will not punch holes in your floor. They will sit on top of your main stringers. Besides, you'll find that there really isn't much weight on them. The front engine mounts carry a good percentage of the load.

So . . . has anyone experienced this who wants to share some tips or maybe some of the pitfalls Tim mentioned?

I redid my '82 without issue. Easy peasy lemon squeezy. But if i had to do another i'd just mail it to eric. He can save parts that we would have to throw away, and he can identify parts ready to fail that we can't. Don't let pride get in the way of a good decision.

Once you figure out the cost of parts you will find that Eric is a good deal.


Tim

ha, you guys kill me but thanks....
but i have a guy that stops in all the time and barrages me with questions...I seriously tell him "you get 3 questions" and he will say what do you mean? i will tell him "you just used up one of your questions..like I said last week a kid called me 12 times on his tranny but he got thru it...and it works, i teared up

skftz, even though I rebuilt my own with decent results, when it comes time to do a major job on my boat (which won't be long), I'll be sending my tranny to Eric. When I put it all back together, I want to make sure it's perfect this time.

I called Eric last week and discussed my situation. He's going to get the tranny.

I removed it from the boat this afternoon. First I removed the shaft at the flange. Then I supported the rear of the engine on jacks and unbolted the rear mounts from the bracket on the stringers. Then I separated the bellhousing from the engine. Then I slid the tranny back with a little prying and lifted it out of the boat. Then I put blocks under the engine for when the jacks sag.

After that I brought the whole thing to town where I separated the bellhousing from the tranny. As soon as I find an 11/16 box-end (really, wtf is the deal with so many different sized hex-heads on this thing? Gimme a Toyota where 10s, 12s and 14s are 95% of the hex heads any day . . .), I'll have the mounts off and will be able to put it the hands of the fed-ex man.

Here are some questions:

1. Should I mount the bellhousing to the engine before I re-mount the tranny?

2. Does this look like a normal configuration for a rear mount? (photo shot across top of tranny from starboard to port -- that's the shift lever in the lower left of the pic) Seems like the actual "mount" wouldn't be absorbing much shock/vibration. Also note that I was half-way through removing the mount when the photo was shot (see comment re 11/16 nut . . .)


3. Can someone point me to a link (with photos preferably) to a shaft alignment thread where this type of mount is shown or discussed?

Thanks in advance!

--Shawn

I have a question that I thought one of you guys might could help me with. i tried to search for an answer, but I couldn't find one.

Anyway, I just bought a 80 ski tique with a trashed engine. I have a brand new engine ready to drop in, but the transmission doesn't want to slide off of the old engine. I removed the engine and trans from the boat in one piece and removed the bolts from the bell housing. The trans slid out about a 1/4 of an inch and won't go any further. I didn't want to break anything, so I figured I'd ask someone before I started snatching on it. Any help would be greatly appreciated. I'm trying to get it on the water by the weekend.

8122pbrainard wrote: Is the new engine the proper rotation?

first thing that came to me when he sais engine replaced..

You would have also had to take the pistons off the rods and give then a 180. Another crises averted.

Topher170 wrote:    I sprayed pb plaster onto the shaft After about an hour I gave it a couple gentle smacks with the good ole dead blow and it came right off.

Christopher,
The only mistake you made is falling for the advertising hype and bought the PB blaster!! Seriously, we just had a post not too long ago where the testing results of different rust busting lubricants were listed. PB I believe was 2nd from the bottom just over plain old 3in1 oil. The 50/50 mix of ATF and a solvent was at the top and then right below it was the Kroil.

Glad you got it off.

BTW, don't even get me going on WD40!!

btw, I've never seen an advertisement for pb blaster. Maybe it isn't as popular in the south. I just had a conversation about it with a few of my friends and none of them had ever even heard of it.

I'm going to mix up a batch of atf and solvent now. The main pully is being a pain. I've always been satisfied with pb, so I should love the kroil or home brew.

i recieved one yesterday but didnt look, I'll look this morning...there goes my weekend lol