Help! C6 Not Shifting

Clutch, transmission, rear axle

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colnago
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Help! C6 Not Shifting

Post by colnago »

All,

I have a '67 with a 352FE. Somewhere in its life, it received a C6. Today, I was working on the carb, and had a small engine fire. I forgot to hook the fuel line back to the carb. :oops: It was enough to melt the air filter riser (plastic, on an Edelbrock), and burn the filter. I replaced riser and filter, replaced damaged fuel ines and inline filter, and she fired right up ... ummm, started right up. Unfortunately, the C6 no longer shifts.

It will go into reverse. If I put it in 2nd, then it shifts up to 2nd, although I can't feel the 1-2 shift. I think it stays in 1st if I start in 1st, and starts/stays in 2nd if I start in 2nd. If I put it into 3rd, it stays in gear (1st or 2nd, whatever I was in when I shifted). The throttle linkage is fine (it's never been hooked up to the Eddy, but it moves down manually, and springs back into place when I let go - no hesitation or sluggish movement). The vacuum lines to everything are good or replaced post-fire. The vacuum line to the tranny is clear. The tranny fluid level is fine, and still pink (I changed it a couple of years ago). My brake booster is still boosting.

I'm not sure what else to check. The engine is on its way out, with two bad intake valves, so it's low on total vacuum - but it shouldn't be that low! I'm sure that I have melted wires under the hood, but the C6 isn't controlled electronically. Any pointers?

Thanks,

Joseph
"Sugar", my 1967 Ford F250 2WD Camper Special, 352FE, Ford iron "T" Intake with 1405 Edelbrock, Duraspark II Ignition, C6 transmission, front disc brake conversion.
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BobbyFord
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Re: Help! C6 Not Shifting

Post by BobbyFord »

If you have a hand vacuum pump, connect it at the carb end of the modulator line and see if the line holds vacuum.
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colnago
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Re: Help! C6 Not Shifting

Post by colnago »

Found it! I was ready to test the vacuum all the way up, then found an old post that said the vacuum modulator is connected to the hard line by a short rubber hose. Sure enough, that 6" hose was burnt to a crisp. That's where my vacuum loss was! :doh: A new chunk of hose, and I'm back on the road. The bottom of the C6 looks like a BBQ, but it's reinvigorated me to get back onto the task of rebuilding my spare engine and spare tranny.

Thanks, everyone!

Joseph
"Sugar", my 1967 Ford F250 2WD Camper Special, 352FE, Ford iron "T" Intake with 1405 Edelbrock, Duraspark II Ignition, C6 transmission, front disc brake conversion.
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Mancar1
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Re: Help! C6 Not Shifting

Post by Mancar1 »

:thup:
May your sails stay full, and your knots not slip. Unless a slip knot.
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1972hiboy
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Re: Help! C6 Not Shifting

Post by 1972hiboy »

lol you must have quite a weiny roast on top of your engine to get that hose. Glad you found the problem of your no shifting and your fuel line. :thup:
Rich
1973 f350 super c/s 460/c6 22k orig miles
1972 f350 srw crewcab special 390
1972 f250 4x4 sport custom 390fe Red
1972 f250 4x4 custom 360 FE " Ranger Ric"
1972 f250 4x4 custom 84k og miles 390
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colnago
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Re: Help! C6 Not Shifting

Post by colnago »

Kinda funny after the fact. All I can figure is that the gas fell down on the rubber vacuum line by the regulator, which caught on fire, it got cooked, and created my vacuum leak. You know, in the movies, a gas fire makes a huge explosion; in reality, it just makes a $#@£%! mess! :lol:

Joseph
"Sugar", my 1967 Ford F250 2WD Camper Special, 352FE, Ford iron "T" Intake with 1405 Edelbrock, Duraspark II Ignition, C6 transmission, front disc brake conversion.
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