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Old 09-15-2011, 08:17 PM   #1
jocko
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speedo cable leaking?!?

Dumb question - Had no speedo cable connected to my T5 for a few weeks (just sitting in the garage anyway) and noticed a puddle of trans fluid underneath it. Installed a cable extender and even sealed it with thread sealant.

Now, after being gone for a week, I come back and find another puddle, still obviously coming from the speed cable connection. What the?

Should the speedo cable connection leak without any cable connected?

I KNOW it shouldn't leak WITH one connected, so, any idears??

Thanks all.

EDIT: Oh yeah 0 I guess this is another dumb question - are the cables the same size for the stock 3-speed and the T5? Both have the 7/8" coupling, but I'm talkin about the actual square cable fit. I noticed that when I connected my "new" extension to my "old" cable - it was a very tight fit - almost TOO tight... i.e. the square female adapter BARELY fit over the old stock square cable. The end of the adapter that plugged into the trans seemed to fit just fine. (maybe it was loose??) Also, noted that the actual fitting for the mech speedo hookup that is inserted into the trans moves about a little bit, and is restrained by the little hold-down that keeps it in place - but still can rotate it/move it in n out just a LITTLE bit - which I thought was ok. Should that sucker be REALLY tight in the trans? (I'm talkin about the speedo hookup in the trans, forget about the cable discussion for a second - the "connection" only is what I'm talkin about should it be real tight? I thought it was just kept in with an o-ring)

Last edited by jocko; 09-15-2011 at 08:32 PM.
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Old 09-15-2011, 11:55 PM   #2
markeb01
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Re: speedo cable leaking?!?

To begin I haven't looked at a T5 in over 20 years so I'm hardly current. But from the one picture I've seen it appears speedo drive is below the fill plug, so I would expect it to leak if left open. Did your T5 come with an electronic sender and you switched it over to a mechanical drive, or did it come with a mechanical drive originally?

If it's leaking at the transmission/speedo adapter I'd wonder if the O-ring around the adapter is missing or doesn't fit. If it's leaking through the cable jacket, it sounds like there may be a defect or hole in the driven gear, or there may be an internal O-ring missing. There shouldn't be any trans fluid in the cable jacket.
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Old 09-18-2011, 11:16 AM   #3
bama63
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Re: speedo cable leaking?!?

if you remove the speedo drive you will find a seal (or o-rings) just under the gear and in good condition shouldn't leak without the cable installed, i have used the old muncie 4 speeds for years in my race cars without speedo cables and they never leaked but i did have one in a 70 chevelle ss that leaked and pulled oil all the way up to the speedo head and dripped on my feet lol
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Old 09-18-2011, 02:30 PM   #4
jocko
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Re: speedo cable leaking?!?

I simo posted over on the drivetrain forum. You're both exactly right, THANKS! In the process of checking this out a few days ago, yanked the speedo gear housing and discovered the entire inner seal was never installed by the "rock star" that rebuilt the trans. Well, ya buy one at a swap meet and ya takes yer chances! Still tickled pink with the trans, this was a $6 fix. Now good to go. Pics below if anyone interested. Thanks for the replies folks, much appreciated!

Markeb01, the guy that was sellin it at the swap meet said he installed the mech speedo gear hsg - it was originally an electronic hookup for a 93 trans.

Interestingly enough, when I pulled the hsg, only a dribble came - probably because it had all leaked out already! But low point in housing is only about "1/3 quart" below the fill hole, so at least I didn't take another ATF bath. Didn't even need to go to the parts store for more fluid either.

And again, both correct - all fluid should remain inside the trans if both seals working correctly, even if no cable installed - and it should never leak into the cable - but will if the small seal is shot. A little got into mine, but mostly just dribbled onto the floor - not my feet, luckily. Whew!

Now, if I could just finish plumbing my brake lines, I could this this thing on the road!

http://67-72chevytrucks.com/vboard/s...d.php?t=484616

Last edited by jocko; 09-18-2011 at 02:37 PM.
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