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Old 02-14-2024, 06:20 PM   #1
fotoboy
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350 wont shift out of first...

So... I have a transmission question... I have a 1980 Scotsdale with a (newly rebuilt) 350 and a (newly rebuilt) turbo 350 tranny.

It was shifting fine (beautifully actually), then I installed a manual choke kit on the QJ. Now when I drive it, it does not shift out of first, it acts like it wants to, or is starting to, then it lurches as if it were downshifting, which is bizarre.

When I manually put it in 1st, it doesnt malfunction, but will not shift to second if I manually shift it to 2nd. Thoughts?

Oh... Vac line is good and attached (i made sure it was clear, not clogged but didnt test otherwise), Modulator is new with rebuild...
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Old 02-15-2024, 04:01 PM   #2
old Rusty C10
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Re: 350 wont shift out of first...

are you sure the new modulator is good.. ive seen several new in box parts be bad from the chinese factory.. and the rubber on the line ends is that in good shape?
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Old 02-15-2024, 07:03 PM   #3
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Re: 350 wont shift out of first...

Nice wheel pic but a pic of the motor might help.
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Old 02-15-2024, 07:52 PM   #4
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Re: 350 wont shift out of first...

did you move the detent cable
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Old 02-15-2024, 10:51 PM   #5
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Re: 350 wont shift out of first...

unhook the detent cable and try it.
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Old 02-25-2024, 08:00 PM   #6
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Re: 350 wont shift out of first...

Quote:
Originally Posted by dmb View Post
did you move the detent cable
yes, but completely replaced and adjusted it , also ran it without cable and it ran the same.
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Old 02-25-2024, 08:00 PM   #7
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Re: 350 wont shift out of first...

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Originally Posted by v30crewcab View Post
unhook the detent cable and try it.
check. no difference.
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Old 02-25-2024, 08:01 PM   #8
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Re: 350 wont shift out of first...

Quote:
Originally Posted by old Rusty C10 View Post
are you sure the new modulator is good.. ive seen several new in box parts be bad from the chinese factory.. and the rubber on the line ends is that in good shape?
fair enough. replaced the modulator and got same result.
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Old 02-25-2024, 08:08 PM   #9
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Re: 350 wont shift out of first...

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Originally Posted by geezer#99 View Post
Nice wheel pic but a pic of the motor might help.
sure, I didnt think the engine photos would matter, dealing with the transmission...
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Old 02-25-2024, 08:08 PM   #10
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Re: 350 wont shift out of first...

I also have a video if anybody thinks it would help...
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Old 02-25-2024, 08:19 PM   #11
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Re: 350 wont shift out of first...

Sure, play it.

Does your choke blade open all the way with the choke knob pushed in all the way?
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Old 02-25-2024, 08:46 PM   #12
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Re: 350 wont shift out of first...

the detent cable ib not adjusted , it is all the way in , it would act like it was at wot all the time. pull up the plunger and hold the throttle wide open then push the plunger down
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Old 02-26-2024, 10:33 AM   #13
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Re: 350 wont shift out of first...

Quote:
Originally Posted by geezer#99 View Post
Sure, play it.

Does your choke blade open all the way with the choke knob pushed in all the way?
Yes, but how does a choke effect the transmission?
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Old 02-26-2024, 10:43 AM   #14
fotoboy
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Re: 350 wont shift out of first...

Quote:
Originally Posted by dmb View Post
the detent cable ib not adjusted , it is all the way in , it would act like it was at wot all the time. pull up the plunger and hold the throttle wide open then push the plunger down
That is exactly how I adjusted it... (it is not the OEM cable) and is hard to see in the photo... (submitting new photo) but will double check that anyway. Thanks
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Old 02-26-2024, 04:42 PM   #15
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Re: 350 wont shift out of first...

Disconnect your manual choke set up and wire the choke wide open then test drive it.
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Old 02-26-2024, 07:09 PM   #16
fotoboy
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Re: 350 wont shift out of first...

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Originally Posted by geezer#99 View Post
Disconnect your manual choke set up and wire the choke wide open then test drive it.
Ok, for fun I tried that, no difference what so ever.
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Old 02-26-2024, 08:02 PM   #17
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Re: 350 wont shift out of first...

Time to explore yours transmission warranty.
Could be governor.
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Old 03-01-2024, 07:12 PM   #18
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Re: 350 wont shift out of first...

Quote:
Originally Posted by old Rusty C10 View Post
are you sure the new modulator is good.. ive seen several new in box parts be bad from the chinese factory.. and the rubber on the line ends is that in good shape?
It took me quite few to get one that works right....
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Old 03-02-2024, 02:54 AM   #19
Accelo
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Re: 350 wont shift out of first...

Sometimes the plastic gear on the governor shears. Pull the governor and check.
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Old 03-02-2024, 08:45 AM   #20
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Re: 350 wont shift out of first...

Do you have a metal line to your vacuum modulator (just rubber line for connections)? If not, the vacuum will suck the line shut.

Vacuum connected to a manifold vacuum source? If connected to a carb make sure you are not on a ported line.

You can drive a th350 with the kickdown cable disconnected (its not a tv cable like an overdrive trans). When you disconnect the kickdown cable does it spring/pull back towards the trans? (too tight if it does).
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