C-6 Modulator adjustment

[junker39]

I searched and didn't find quite the right answer. '79 C-6 from a F150/460. Newly rebuilt, shifts fine, just too fast. Even when accelerating a little. It goes 1,2,3, OK, but no pause in second before hitting third. I can barely get to 20mph before it's in third. It's got enough power so it's not really hurting anything. I can probably get it act right by the modulator adjustment. I should screw the adjustment IN, correct? Start with about half a turn? And is that an allen screw in there or slotted for a flat screwdriver? Somebody built this thing where I can't see it, even with a mirror. Idiot engineer. Thanks for any help.

[tmgant]

First pull the modulator out and ck for the pin. 2nd ck for proper length, the mod should be .060-.090 out from seat by hand then install hold-down. So you preload the valve .060-.090. 3rd if it has a screw turn all the way in, start from there. Tobby ps maybe a governor problem but this first.

[junker39]

Thanks tmgant. I'm going to get a new modulator if I have to pull this one. Just trying to avoid that. This thing had been sitting for a couple of years before it got used. It's possible it got stuck while waiting. I'm positive it's installed correctly. I checked everything, by the overhaul manual, measured it all, and made sure there wasn't any guess work. I'm thinking my vacuum may not be up to the preset on the modulator. It'll be next weekend before I get a chance to mess with it. Until then, I'm just going to drive it. Thanks again for the input.

[Hollow65]

If it sat I'd replace it. They're cheap enough. If they go bad it could feed fluid into the engine. Best of luck

[junker39]

I've had that happen a few times over the years. It'll sure give you a scare when you start a rebuild up and it smokes. I learned the smoke smells different between motor oil and ATF. Thanks.

[Hollow65]

My went out a few months ago, 14 years of abuse. Take care.