throttle sticking when load is on

[Buck]

Ok, here's an interesting one. When I'm at idle the throttle does not stick. When I put a load on it and get to where the stall kicks in at about 2,300 rpm the throttle goes crazy and the car just wants to take off. It's pretty scary. This happen to anybody before?

 

[live4theking]

First, what are you working on?

Did this just start?

What have you changed recently if this has just started?

My throttle wasn't returning like I would like. When I looked into it I realized that there was only one throttle return spring. I removed it and went back to the double spring setup. Problem solved.

 

[Buck]

First, what are you working on?

Did this just start?

What have you changed recently if this has just started?

My throttle wasn't returning like I would like. When I looked into it I realized that there was only one throttle return spring. I removed it and went back to the double spring setup. Problem solved.

It's a 68 polara wagon. Recently installed a 451 stroker and a 727. 2,400 stall. I ran it for a while getting the kickdown linkage set and then it started just taking off like a bad out of hell after the stall kicked in. I doubled the springs to prevent any sticking but it's so severe that it's apparent there's something else at play here.

 

[commando1]

What has your thorough examination of all the throttle linkage and all of the moving parts on the carburetor shown you.

 

[azblackhemi]

Broken motor mount?

 

[Buck]

What has your thorough examination of all the throttle linkage and all of the moving parts on the carburetor shown you.

Everything is moving very free. I'm really having a hard time with this

 

[Buck]

Broken motor mount?

I was actually thinking about that. The motor seems to have more play than I would like. Why would that make it do what it's doing? I'm new at this

 

[azblackhemi]

I was actually thinking about that. The motor seems to have more play than I would like. Why would that make it do what it's doing? I'm new at this

When you accelerate the motor will raise up and pull on the throttle linkage.

 

[GJS]

I ran a solid motor mount on my 68 Monaco after building my 440... I never ran it without so I can't really reference but theoretically, it could be the mount.

 

[bluefury361]

My money is on the motor mount, probably the driver side. Open the hood, sit in the car and slightly brake torque while watching through the hood opening. Engine should only slightly rock, not lift up. Sometimes you can see the hood actually flex up while closed.
I'm not sure when it started but Chrysler installed "torque cables" that act as a tether just for this purpose. Both my 69's have these. It's not unusual to find them deleted after a engine R&R.

 

[traintech55]

I ran a solid motor mount on my 68 Monaco after building my 440... I never ran it without so I can't really reference but theoretically, it could be the mount.

Okay guys, these are not generic Motors cars. The reason Chrysler went to the throttle cable was to prevent this. It sounds like you have done some heavy modifications to your engine, so here are some things to look for.
1. Engine mounts, if the drivers side is broken the engine will rise up real high in the compartment under load in drive. If broken contact Schumacher for a set of poly loc mounts.
2. Make certain you have enough slack in the cable, or that now with the modifications not binding, also the cable should be on as straight a line as possible to the carb, (no crazy curves).
3. Make sure your return springs are also in a straight line with the carb, no weird angles. You may have to bend your brackets slightly to get this.
4. Since you have switched so many parts use a double return spring.
If you still have problems attach some pictures of the linkage.

 

[bluefury361]

If your using an non original/aftermarket air filter housing, check for interference throughout the throttle range.

 

[Buck]

It's the motor mount! Thanks guys!

 

[bluefury361]

Halifax NS ........ Is it a greenish black New Yorker with the right front door missing.....?

 

[Buck]

Halifax NS ........ Is it a greenish black New Yorker with the right front door missing.....?

No, but I know the car quite well. There's always a hockey stick on the back seat floor.

 

[twostick]

Those PolyLocs are a great idea but a bad execution.

The Loc part works but the Poly part melts.

Kevin