Please help with a slow TH350 leak.
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Joined: Aug 2010
Posts: 57
Likes: 2
From: Denton TX
Please help with a slow TH350 leak.
I have been nursing a slow leak from my automatic TH350 all winter(for reference, car is an early '76). After a lot of hunting I have narowed it down to the detent control cable on the passenger side of the car, just behind the bell housing. It has a plastic boot on the last two inches where it bolts to the transmission. The plastic is yellowing and my guess is it's brittle too. I tightend the bolt that holds it on and that worked for about 2 weeks until the temps dipped low again. I'm affraid to torque the bolt any more for fear that the whole boot will split and make a worse problem.
I think I have found the replacement cable on the vender sites, but is there a seal I need as well that goes in first? Here is the link for the correct cable I believe; http://www.parts123.com/parts123/yb....Z5Z5Z50000050G
I can't get a socket on the bolt at the boot, just a small adustable wrench because of where the exhaust and the cooling lines to the radiator are located. Also, I'm a little scared of detatching the carborater end of the cable and getting a new one back on without screwing something up (carbs scare me
). What am I in for????
I think I have found the replacement cable on the vender sites, but is there a seal I need as well that goes in first? Here is the link for the correct cable I believe; http://www.parts123.com/parts123/yb....Z5Z5Z50000050G
I can't get a socket on the bolt at the boot, just a small adustable wrench because of where the exhaust and the cooling lines to the radiator are located. Also, I'm a little scared of detatching the carborater end of the cable and getting a new one back on without screwing something up (carbs scare me
). What am I in for????
Pro
Joined: Feb 2012
Posts: 577
Likes: 6
I have been nursing a slow leak from my automatic TH350 all winter(for reference, car is an early '76). After a lot of hunting I have narowed it down to the detent control cable on the passenger side of the car, just behind the bell housing. It has a plastic boot on the last two inches where it bolts to the transmission. The plastic is yellowing and my guess is it's brittle too. I tightend the bolt that holds it on and that worked for about 2 weeks until the temps dipped low again. I'm affraid to torque the bolt any more for fear that the whole boot will split and make a worse problem.
I think I have found the replacement cable on the vender sites, but is there a seal I need as well that goes in first? Here is the link for the correct cable I believe; http://www.parts123.com/parts123/yb....Z5Z5Z50000050G
I can't get a socket on the bolt at the boot, just a small adustable wrench because of where the exhaust and the cooling lines to the radiator are located. Also, I'm a little scared of detatching the carborater end of the cable and getting a new one back on without screwing something up (carbs scare me ). What am I in for????
I think I have found the replacement cable on the vender sites, but is there a seal I need as well that goes in first? Here is the link for the correct cable I believe; http://www.parts123.com/parts123/yb....Z5Z5Z50000050G
I can't get a socket on the bolt at the boot, just a small adustable wrench because of where the exhaust and the cooling lines to the radiator are located. Also, I'm a little scared of detatching the carborater end of the cable and getting a new one back on without screwing something up (carbs scare me
). What am I in for????Replacing the detent cable is not difficult at all. First remove the linkage end at the carburetor. Take a few reference pictures, inspect it for it's arrangement and remove it. Any parts go in a marked zip lock bag. The bottom end of the cable is a little bit harder. Remove that bolt and the base will be free to lift up a little bit. The cable in the base has a hook at the bottom that's from the transmission. Watch for it as you slowly pull the base up out of the transmission. The hook won't fall too far in so don't worry. Once unhooked simply fish the cable out. The new cable will have an o ring seal so it's just reverse order. Put the hook through the hole, seat the base, start ad tighten the bolt, reconnect the throttle end as it came off and you're done.
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
Disconnecting at the carb is easy. Pull the cable out to get the wide opening in the slot to the tab on the carb linkage. One thing to consider, if you are concerned about full throttle upshift points and the new cable is slightly different in length than the old cable, you need to reset the cable in the support bracket near the carb. With the new cable connected at both ends, just release the tab in the black piece on the cable, open the carb throttle wide and reclamp the tab, then close the trottle. If this isn't done, your WOT shift points will change.
Pro
Joined: May 2011
Posts: 581
Likes: 5
From: BC
Likely no need to replace the detent cable if it's just leaking. Replace the rubber o-ring on the cable housing that enters the trans. While you have the oil drained down a little do the one on the dipstick tube as well. Another common area of leakage.
Steve g
Steve g
Thread Starter
Advanced
Joined: Aug 2010
Posts: 57
Likes: 2
From: Denton TX
Thanks fellas,
Looks pretty straight forward. If I get in trouble on the carb end, I'll just do a thread search or post again.
I have narrowed the leak down to right between where the black cable meets the white plastic boot (was white now yellowish from age/heat). The new cables have a black plastic boot, hopefully made from a stronger longer lasting plastic.
Will the tranny spew a lot of fluid when I disconnect the cable? I did the speedo cable bullet last winter and it was not too bad.
Looks pretty straight forward. If I get in trouble on the carb end, I'll just do a thread search or post again.
I have narrowed the leak down to right between where the black cable meets the white plastic boot (was white now yellowish from age/heat). The new cables have a black plastic boot, hopefully made from a stronger longer lasting plastic.
Will the tranny spew a lot of fluid when I disconnect the cable? I did the speedo cable bullet last winter and it was not too bad.
Pro
Joined: May 2011
Posts: 581
Likes: 5
From: BC
Thanks fellas,
Looks pretty straight forward. If I get in trouble on the carb end, I'll just do a thread search or post again.
I have narrowed the leak down to right between where the black cable meets the white plastic boot (was white now yellowish from age/heat). The new cables have a black plastic boot, hopefully made from a stronger longer lasting plastic.
Will the tranny spew a lot of fluid when I disconnect the cable? I did the speedo cable bullet last winter and it was not too bad.
Looks pretty straight forward. If I get in trouble on the carb end, I'll just do a thread search or post again.
I have narrowed the leak down to right between where the black cable meets the white plastic boot (was white now yellowish from age/heat). The new cables have a black plastic boot, hopefully made from a stronger longer lasting plastic.
Will the tranny spew a lot of fluid when I disconnect the cable? I did the speedo cable bullet last winter and it was not too bad.
You will have a lot less oil, and maybe none, if you run it just before you pull the cable out of the case. Takes a while for the fluid to drain back down so if you disconnect everything from the top, run it for a moment then shut it off and pull the bottom out you can have the new one in before the level rises much. Used to do this all the time on those.
Steve g
Thread Starter
Advanced
Joined: Aug 2010
Posts: 57
Likes: 2
From: Denton TX
Oh crap....now I did it. NOW WHAT?
I took the old detent cable off and had the new one on ..not too bad. But, as I was finishing up, I noticed a little transmission fluid around the new cable boot at the transmission end. I tried to tighten the bolt a little more and with just a slight turn it let go. I was worried about over torquing it and sure enough I stripped it. I was hoping it was the bolt, so I backed it out, but sure enough the bolt is clean with metal filings on the threads.
So what are my options now? My guess is its going to be expensive
I took the old detent cable off and had the new one on ..not too bad. But, as I was finishing up, I noticed a little transmission fluid around the new cable boot at the transmission end. I tried to tighten the bolt a little more and with just a slight turn it let go. I was worried about over torquing it and sure enough I stripped it. I was hoping it was the bolt, so I backed it out, but sure enough the bolt is clean with metal filings on the threads.
So what are my options now? My guess is its going to be expensive
Pro
Joined: Feb 2012
Posts: 577
Likes: 6
Oh crap....now I did it. NOW WHAT?
I took the old detent cable off and had the new one on ..not too bad. But, as I was finishing up, I noticed a little transmission fluid around the new cable boot at the transmission end. I tried to tighten the bolt a little more and with just a slight turn it let go. I was worried about over torquing it and sure enough I stripped it. I was hoping it was the bolt, so I backed it out, but sure enough the bolt is clean with metal filings on the threads.
So what are my options now? My guess is its going to be expensive
I took the old detent cable off and had the new one on ..not too bad. But, as I was finishing up, I noticed a little transmission fluid around the new cable boot at the transmission end. I tried to tighten the bolt a little more and with just a slight turn it let go. I was worried about over torquing it and sure enough I stripped it. I was hoping it was the bolt, so I backed it out, but sure enough the bolt is clean with metal filings on the threads.
So what are my options now? My guess is its going to be expensive
You can fix it yourself but to do it right you'll want to drop the transmission. Metal is now in the fluid and you will probably have to tap the hole larger or use a helicoil kit to use the original bolt.
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