Author Topic: TH350 Yoke Weep Hole Leak  (Read 489 times)

Offline LILT77

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TH350 Yoke Weep Hole Leak
« on: March 17, 2022, 05:08:59 PM »
I’m leaking fluid out of the weep hole that’s drilled in the center of the yoke, right behind the u-joint. I believe this is there to relieve pressure from the yoke slipping in and out during operation. I have read that many people have welded/used epoxy to seal this hole, and have read that people advise against that because you are effectively shutting off a vent. Any thoughts on this??...will I be safe if I plug the weep hole?
77 C10/Big 10 Cheyenne "Old Blue"
81 C2500 Sierra Grande "Gramps"

Offline JohnnyPopper

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Re: TH350 Yoke Weep Hole Leak
« Reply #1 on: March 17, 2022, 05:39:56 PM »
Doesn't make sense that there would be a vent there. Why?

Seal it.  8)
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline VileZambonie

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Re: TH350 Yoke Weep Hole Leak
« Reply #2 on: March 17, 2022, 06:27:58 PM »
Temporary fix, pack some rtv in the hole but the correct fix is to remove the extension housing and replace the o-ring on the cup. There are some more posts about this on the forum if you search.
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Online bd

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Re: TH350 Yoke Weep Hole Leak
« Reply #3 on: March 17, 2022, 07:26:49 PM »
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline LILT77

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Re: TH350 Yoke Weep Hole Leak
« Reply #4 on: March 17, 2022, 07:43:39 PM »
Perfect, that link is exactly what I needed. Thanks guys!
77 C10/Big 10 Cheyenne "Old Blue"
81 C2500 Sierra Grande "Gramps"

Offline wz7u

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Re: TH350 Yoke Weep Hole Leak
« Reply #5 on: March 17, 2022, 09:38:53 PM »
Thanks for that, I book marked it for future reference. I wonder, does TH400 have a similar seal? I would expect it probably does...
'79 C20 454/th400 "Pearl"

Offline Irish_Alley

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Re: TH350 Yoke Weep Hole Leak
« Reply #6 on: March 19, 2022, 10:14:51 AM »
the vent is there so when the suspension travels it will compress and extends the slip yoke. if there was no vent the pressure could do something that engineers saw to be a problem lol. but ideally its not an issue if the seal is good
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

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