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Old 12-16-2010, 02:19 AM   #1
mwilliams5891
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my truck accelerates when i push in the clutch

So yeah my 69 c/10 accels. when i push in my clutch and it will go down MOST of the time if i rev the engine...so any help would be nice.

By the way 250 CID with a Holley 390 CFM 4 barrel on it
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Old 12-16-2010, 04:10 AM   #2
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Re: my truck accelerates when i push in the clutch

anyone know why?
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Old 12-16-2010, 06:18 AM   #3
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Re: my truck accelerates when i push in the clutch

It sounds like there is some movement of the engine. Can you have someone watch the engine when you depress the clutch?

Jim
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Old 12-16-2010, 08:52 AM   #4
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Re: my truck accelerates when i push in the clutch

Could possibly the choke and/or fast idle be not completely releasing?
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Old 12-16-2010, 03:43 PM   #5
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Re: my truck accelerates when i push in the clutch

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Could possibly the choke and/or fast idle be not completely releasing?
that is what i was thinking. since its an electric choke could it just not have enough power?
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Old 12-16-2010, 03:44 PM   #6
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Re: my truck accelerates when i push in the clutch

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It sounds like there is some movement of the engine. Can you have someone watch the engine when you depress the clutch?

Jim
so what should i look for exactly? i dont mean to sound like a smart a** just wondering
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Old 12-16-2010, 03:50 PM   #7
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Re: my truck accelerates when i push in the clutch

Watch and see if your motor is rocking side to side when you press the clutch or rev the motor. If it does, you may need new motor mounts.

I'm not sure why the motor would move when you press the clutch though...
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Old 12-16-2010, 03:53 PM   #8
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Re: my truck accelerates when i push in the clutch

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Watch and see if your motor is rocking side to side when you press the clutch or rev the motor. If it does, you may need new motor mounts.

I'm not sure why the motor would move when you press the clutch though...
ok will do
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Old 12-16-2010, 05:12 PM   #9
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Re: my truck accelerates when i push in the clutch

ttt
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Old 12-16-2010, 05:44 PM   #10
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Re: my truck accelerates when i push in the clutch

I would suggest you also look at the linkage/cable for the throttle.It could be hung on the clutch linkage.Or the wiring for the electric choke could be shorting on the linkage.A fast idle solenoid could cause this also if it were shorting or maybe misadjusted.
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Old 12-16-2010, 05:45 PM   #11
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Re: my truck accelerates when i push in the clutch

There is minimal info here - and I am not familiar with the inline 6 lever/linkage setup for clutch and accelerator operation, but the first logical thought seems to be that there is some minor interplay between the two. Just a suggestion - observe the under-hood operation of the clutch linkage and see if in its travel it is in some way touching or engaging the accelerator linkage. Hope this helps.
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Old 12-16-2010, 05:48 PM   #12
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Re: my truck accelerates when i push in the clutch

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Originally Posted by splehigh View Post
Watch and see if your motor is rocking side to side when you press the clutch or rev the motor. If it does, you may need new motor mounts.

I'm not sure why the motor would move when you press the clutch though...
What do I do if my whole truck shakes
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Old 12-16-2010, 06:07 PM   #13
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Re: my truck accelerates when i push in the clutch

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What do I do if my whole truck shakes
Play Chuck Berry music(smart a$$ grin).
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Old 12-16-2010, 06:12 PM   #14
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Re: my truck accelerates when i push in the clutch

is this happening while parked and in neutral with the foot off the accelerator pedal completely?
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Old 12-16-2010, 07:18 PM   #15
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Re: my truck accelerates when i push in the clutch

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is this happening while parked and in neutral with the foot off the accelerator pedal completely?
yes this will happen if i stop at a stop sign or im slowing down to stop or pretty much anytime i engage the clutch.
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Old 12-16-2010, 07:20 PM   #16
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Re: my truck accelerates when i push in the clutch

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Originally Posted by CCCC View Post
There is minimal info here - and I am not familiar with the inline 6 lever/linkage setup for clutch and accelerator operation, but the first logical thought seems to be that there is some minor interplay between the two. Just a suggestion - observe the under-hood operation of the clutch linkage and see if in its travel it is in some way touching or engaging the accelerator linkage. Hope this helps.
I will observe but I am almost 100% nothing is touching or anything like that. i could be wrong but i am pretty sure.

what kind of info do you guys need? I really said everything that happens...so I dont know what else to provide so you guys can help me sort out this problem
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Old 12-16-2010, 07:20 PM   #17
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Re: my truck accelerates when i push in the clutch

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Originally Posted by PanelDeland View Post
I would suggest you also look at the linkage/cable for the throttle.It could be hung on the clutch linkage.Or the wiring for the electric choke could be shorting on the linkage.A fast idle solenoid could cause this also if it were shorting or maybe misadjusted.
what does a fast idle solenoid look like?
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Old 12-16-2010, 07:21 PM   #18
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Re: my truck accelerates when i push in the clutch

here is what I would like you to try. park the truck. hold your foot on the brake. put the truck in neutral. push the clutch in and let it out. does the RPM change when you do this?
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Old 12-16-2010, 07:24 PM   #19
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Re: my truck accelerates when i push in the clutch

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here is what I would like you to try. park the truck. hold your foot on the brake. put the truck in neutral. push the clutch in and let it out. does the RPM change when you do this?
I will go do that right now


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Old 12-16-2010, 07:28 PM   #20
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Re: my truck accelerates when i push in the clutch

what is the most recent repair right BEFORE this issue started?

is your carb adjusted properly, possibly when you release the load of the drivetrain via the clutch you are letting the motor return to its set idle speed... just a thought.
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Old 12-16-2010, 08:42 PM   #21
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Re: my truck accelerates when i push in the clutch

I had a similar problem in an old jeep I had. Every time the engine was under and increased load (rolled up to a rock or log), the engine rpm would go up. Push in the clutch and rpms would drop off. Turned out to be wasted engine mounts. When the engine was under load, it twisted in the mounts. This would stretch the throttle cable between the carb and firewall, opening the throttle plates and stroking the accelerator pump. Check your mounts.
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Old 12-17-2010, 08:15 AM   #22
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Re: my truck accelerates when i push in the clutch

Quote:
Originally Posted by don t. - 72gmc View Post
Play Chuck Berry music(smart a$$ grin).
LOL
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Old 12-17-2010, 10:54 AM   #23
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Re: my truck accelerates when i push in the clutch

Check the bellhousing bolts, make sure all of them are tight so that the engine don't move foward as the clucth is being depressed, wouldnt take much to affect the 69's rod style throttle arrangement..just a thought...
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