Over 25 Years Later, Finally My 71 C-10 Truck Build

[hgs_notes]

yesterday I think I got the alternator working. The voltage while running was about 13.6 and the battery voltage went up slightly during my test drive. Also got the temp gauge on the dash hooked up. I almost burnt up the wires to the starter where they were against the header. I didn't see it when I was getting everything tied up out of the way, but seems ok.

The timing by ear and vacuum seems pretty close. It was really running pretty nice yesterday afternoon, so I wiped the dust off and told the wife we were going to town. Then during the trip it started smoking like hell. I pulled over and open the hood, nothing wrong there. Look underneath and fluid is draining out of the torque converter dust cover and getting on the hot exhaust. Crap, turn around and drive it home. No issues with the tranny shifting or anything. Just leaking and burning off.

This morning I pulled the dust cover and it for sure is tranny fluid, which is a relief, not the rear main engine seal. Not a difficult fix if you have a lift. Working under the truck on the floor though, trying to drop the tranny enough to pull the torque converter, just plain sucks. So I talked to the local mechanic here in town. He has 3 lifts and can fix it in a few hours, which is worth the money to me right now with so many projects going on.

Here's the rub, I had planned on doing this while it was apart. But when I looked it over there was no sign of leakage at all, so I took the "don't fix what isn't broke" approach. My mistake.

Here's what happens. The pump seal is the last defense for leakage. There is a bushing behind it. There is a small drain back hole between the bushing and seal. When the bushing gets worn there is extra fluid seeping by and eventually it gets bad enough that it overcomes the flow of the drain back hole and puts pressure on the seal.

When I had the truck apart like 7 years ago I replaced the seal but not the bushing. My mistake again. So the bushing has been wearing out and finally overcame the drain and the seal.

The fix is easy enough. Replace the bushing, drill out the drain hole and replace the seal. Easy enough while the tranny is out of the truck, PITA after it's installed.