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sticking accelerator petal-- only when in gear-- 1965 A body
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Author:  gmader [ Tue Apr 24, 2007 6:57 am ]
Post subject:  sticking accelerator petal-- only when in gear-- 1965 A body
Hi all

Well, drat. I have discovered that my throttle sticks open when I floor it, and the car is in gear - This is a 1965 A body, so, it uses the older style shifting on the 904, with a floor mounted shifter, and the linkage style throttle. I tried the obvious answers of replacing the throttle spring, and lubricating all the linkage points. This may be a weird problem, but I am wondering if anybody else has had it, and what specific part needed fixing.

Thanks,

Greg
Author:  SlantSixDan [ Tue Apr 24, 2007 7:23 am ]
Post subject: 
I think it's time for some new engine and trans mounts for you! The most likely scenario is that the engine is moving too much under full throttle and the throttle linkage is being pulled in the direction of "open" via the trans kickdown linkage. This is why later linkage designs (starting from about '69) have a long slot at the top of the kickdown link, such that opening the throttle will push the kickdown rod down, but pulling the kickdown rod down will not open the throttle. You can do a quick check by detaching the kickdown pushrod from the throttle rod bellcrank just in front of the firewall. It's a snap-on ball joint, so just pull or pry the kickdown pushrod rearward towards the firewall and it'll come off. Then close the hood, start the engine, shift into 1, and floor the gas. Does it stick? If not, you've found the problem. I like the polyurethane trans mount from Imperial Services, and someday soon they ought to have '62-'66 A-body slant-6 poly mounts ready to sell.

You'll also want to check all of the adjustments to make sure they're set to spec: The lower kickdown rod (from floor bracket/bellcrank to transmission) has a sliding length adjustment held with a locknut, and the accelerator pedal height adjustment needs to be correct. If it is adjusted too high, the throttle return spring can start to go overcentre at full travel.

Other things to be mindful of: there's a bit of give in the rotating rod setup, so you won't have much to worry about if you install the good 3/8"-thick carb base gasket instead of the original 1/8" item, but if you change from a 170 to a 225, or the other way round, that's a more severe change in the operating angle of the throttle rod, and it can screw up the geometry and make problems.
Author:  gmader [ Tue Apr 24, 2007 8:21 am ]
Post subject: 
You know, Dan, I am having motor mount problems. I had the exhaust pipe contacting part of the steering linkage before, and I "adjusted" the motor mounts to fix that. It sounds like I probably screwed up the throttle linkage when I moved the motor over. I will try your test, and see if I can find a happy medium with the engine position.

My rubber motor mounts are really spongy and flexy. I called Imperial several weeks ago, and they sounded like they might get around to tooling up the polys late this year.

Thanks for the hint, Dan. I gotta figure out a reason to get back to Ontario, and buy you a beer or two.

Greg
Author:  Charrlie_S [ Tue Apr 24, 2007 8:55 am ]
Post subject: 
Quote:
You know, Dan, I am having motor mount problems. I had the exhaust pipe contacting part of the steering linkage before, and I "adjusted" the motor mounts to fix that. It sounds like I probably screwed up the throttle linkage when I moved the motor over. I will try your test, and see if I can find a happy medium with the engine position.

My rubber motor mounts are really spongy and flexy. I called Imperial several weeks ago, and they sounded like they might get around to tooling up the polys late this year.


Greg
If your insulators are that bad, why not just replace them with new rubber ones, while you are waiting for the polys, if and when they ever become available.
Got mounts for my 66 Valiant, from www.motormountz.com
EM-2303 $6.99
EM-2304 $4.99
trans. EM-2272 $5.99
Shipping $10.31
Total $28.28, Cheap enough, to do even on a tempory basis, and a lot safer then having bad mounts.
Author:  gmader [ Tue Apr 24, 2007 9:27 am ]
Post subject: 
Thanks Charrlie. I took your advise, and ordered up a set of motor mounts. I tried the local NAPA, and they don't carry anything that old, so I will see if the motor mounts from the company you referred to will work. They look correct, so we should be okay.

Thanks again,

Greg
Author:  '74 Sport [ Tue Apr 24, 2007 10:28 am ]
Post subject:  Re: sticking accelerator petal-- only when in gear-- 1965 A
Quote:
...when I floor it, and the car is in gear
That's the best time to floor it. :twisted:

Jerry
Author:  Charrlie_S [ Tue Apr 24, 2007 2:21 pm ]
Post subject: 
Quote:
Thanks Charrlie. I took your advise, and ordered up a set of motor mounts. I tried the local NAPA, and they don't carry anything that old, so I will see if the motor mounts from the company you referred to will work. They look correct, so we should be okay.

Thanks again,

Greg
Actually NAPA can get them if you give them the part number. Their catalog is incorrect. However they will charge more then these prices. These mounts are correct for the 63-66 "A" bodies, with a slant six. I have them on hand, and have been using them for years
Author:  gmader [ Sat Apr 28, 2007 9:48 pm ]
Post subject:  Thanks to Dan and Charrlie!
I got two new motor mounts from t he place that Charrlie recommended, and spent an hour putting them in. The test drive confirms that fix also fixed the throttle sticking problem. Dan's theory was correct!

Thanks to everybody here. I will take it to work this coming week a few times, and on to the Mopar Spring Fling track day on Thursday. I look forward to meeting a few more people there, and see some interesting cars.

Greg
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