Help! What did I do wrong? (kick down) - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Truckstr · 11-22-2002, 10:22 AM

Morning all. Even though I'm getting everything together to change the TH350 tranny in my '67 over to a 700R4, I wanted the kick down linkage to work. I've been just putting up with the fact that it didn't work.

I pulled the kickdown cable, the bracket that mounts to the intake and the hook-up at the carburetor off of a '72 C10 that came factory equipped with a TH350. The one that's in my '67 was transplanted in.

So, I get the non-functioning linkage (it wasn't hooked up at the carb - and wouldn't fit) off of the '67. I did notice that the vacuum modulator wasn't even hooked up to a vacuum source

. I install the linkage and bracket from the donor '72.

So far, so good.

Then I take it out for a test spin. The thing won't shift out of first gear! WTH?

I take the kick down linkage loose from the carb and take it back out for a test spin. It STILL won't shift out of first. I fiddle with the linkage to make sure that it wasn't pulled out (engaging the kick down, and take it back out for a spin. It STILL won't shift out of first. WTF?!?

Help!

slam33 · 11-22-2002, 10:40 AM

The kickdown only operates the downshift at WOT. The modulator sounds like it needs to be changed.

Truckstr · 11-22-2002, 11:02 AM

Yeah, I think that it does need to be changed. The thing is though that it wasn't even hooked up before and the tranny shifted fine - harsh from the shift kit - but fine.

I'm not a tranny guy. What does the vacuum modulator do anywho?

Longhorn Man · 11-22-2002, 11:25 AM

Quote:

Originally posted by Truckstr
I did notice that the vacuum modulator wasn't even hooked up to a vacuum source .

Did you plug it in? Plug it in and it'll upshift.

Truckstr · 11-23-2002, 12:00 AM

Okay, she's fixed now.

Apparently, I was mistaken about the modulator not being hooked up before, but the tranny still working. That's what I get for trying to do too much at one time.

Thanks to longhornmail and slam33 for pointing out that the vacuum modulator does, in fact, need to be hooked up

. egg on my face over here.

Man, with the kick down hooked up this truck really hauls. I can't wait to get a 700R4 in it. Then I'll have a rocket launch AND a comfortable hiway cruise.

Always something to do on these old trucks. Great, ain't it!?!

Thanks again guys.

Jeff

TERRYP · 11-23-2002, 03:02 AM

Well, you'll get off the line ok, but I'll be passing you with my 200R4 in second while you are hoping to rev up till the cam kicks in cuz you are bogged down.

Truckstr · 11-23-2002, 12:31 PM

Terryp, how much HP/TQ will the 200R4 take? I don't think that it'll take as much as a 700R4.

The 406 that I'm building should make about 500 ft-lbs of TQ and almost as much HP. What it'll take is the deciding factor with me.

11-22-2002, 10:22 AM	#1
Truckstr Registered User Join Date: Nov 2002 Location: Lebanon, Tennessee Posts: 1,372	Help! What did I do wrong? (kick down) Morning all. Even though I'm getting everything together to change the TH350 tranny in my '67 over to a 700R4, I wanted the kick down linkage to work. I've been just putting up with the fact that it didn't work. I pulled the kickdown cable, the bracket that mounts to the intake and the hook-up at the carburetor off of a '72 C10 that came factory equipped with a TH350. The one that's in my '67 was transplanted in. So, I get the non-functioning linkage (it wasn't hooked up at the carb - and wouldn't fit) off of the '67. I did notice that the vacuum modulator wasn't even hooked up to a vacuum source . I install the linkage and bracket from the donor '72. So far, so good. Then I take it out for a test spin. The thing won't shift out of first gear! WTH? I take the kick down linkage loose from the carb and take it back out for a test spin. It STILL won't shift out of first. I fiddle with the linkage to make sure that it wasn't pulled out (engaging the kick down, and take it back out for a spin. It STILL won't shift out of first. WTF?!? Help! __________________ Jeff '67 short Fleet; my ongoing project. '66 long Fleet; my original "baby." Live life or bust trying.

11-22-2002, 10:40 AM	#2
slam33 Registered User Join Date: Aug 2001 Location: Long Beach, Ca Posts: 1,432	The kickdown only operates the downshift at WOT. The modulator sounds like it needs to be changed. __________________ 71 LWB 350/350still working on it but it's going tp be sweet. www.geocities.com/stevemau/slam33page.html " TARGET=_blank>http://www.geocities.com/stevemau/slam33page.html?1004806705410 </A>

11-22-2002, 11:02 AM	#3
Truckstr Registered User Join Date: Nov 2002 Location: Lebanon, Tennessee Posts: 1,372	Yeah, I think that it does need to be changed. The thing is though that it wasn't even hooked up before and the tranny shifted fine - harsh from the shift kit - but fine. I'm not a tranny guy. What does the vacuum modulator do anywho? __________________ Jeff '67 short Fleet; my ongoing project. '66 long Fleet; my original "baby." Live life or bust trying.

11-23-2002, 12:00 AM	#5
Truckstr Registered User Join Date: Nov 2002 Location: Lebanon, Tennessee Posts: 1,372	Okay, she's fixed now. Apparently, I was mistaken about the modulator not being hooked up before, but the tranny still working. That's what I get for trying to do too much at one time. Thanks to longhornmail and slam33 for pointing out that the vacuum modulator does, in fact, need to be hooked up . egg on my face over here. Man, with the kick down hooked up this truck really hauls. I can't wait to get a 700R4 in it. Then I'll have a rocket launch AND a comfortable hiway cruise. Always something to do on these old trucks. Great, ain't it!?! Thanks again guys. Jeff __________________ Jeff '67 short Fleet; my ongoing project. '66 long Fleet; my original "baby." Live life or bust trying.

11-23-2002, 03:02 AM	#6
TERRYP GYRO GEARLOOSE Join Date: Jun 2000 Location: Nevada City, CAEverett, WA Posts: 361	Well, you'll get off the line ok, but I'll be passing you with my 200R4 in second while you are hoping to rev up till the cam kicks in cuz you are bogged down. __________________ Nevada City, CA Everett, Washington 57 3/4 rat, 235, 3spd 66 C-10 Panel, SWB. 350 from '68, 200R4 tranny, 3.07 rear ratio, restoring 68 C10 LWB 350 4spd, 4.56 rear dump runner 82 Camaro, 305, THM-200-R4 84 Monte Carlo 305 TH350, land tuna 85 Tercel SW, snow runner DISGRACED OUTLAW MEMBER OF THE DRUM BRAKE CLUB

11-23-2002, 12:31 PM	#7
Truckstr Registered User Join Date: Nov 2002 Location: Lebanon, Tennessee Posts: 1,372	Terryp, how much HP/TQ will the 200R4 take? I don't think that it'll take as much as a 700R4. The 406 that I'm building should make about 500 ft-lbs of TQ and almost as much HP. What it'll take is the deciding factor with me. __________________ Jeff '67 short Fleet; my ongoing project. '66 long Fleet; my original "baby." Live life or bust trying.



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.