Hand throttle not allowing throttle to go back to the idle screw?

[Zephyr4]

So, I've swapped a known good engine and trans from a 31 coupe into my 31 tudor. Fired it up for the first time last weekend and it idled way fast.

The throttle was nowhere near the idle adjustment screw:
20180601_124708.jpg

With the hand throttle leaver disconnected at the column, it does return to the stop correctly:
20180520_161411.jpg

But that makes the rod from the column too long:
20180601_124605.jpg

Neither rod is bent. Anyone got any ideas what the problem is? I see I've ended up with a Zenith X which is not stock, maybe that's the difference? I also see that the lever arm on the main accelerator assembly is a bit wobbly looking - I guess someone made some adjustments in the past?

Anyone seen this before?

[Pinesdune]

You can bend the rod that's circled in the pic to make the adjustment you need , like you said it looks like it was bent before

[P.S.]

Yes, have seen that.

Bend the vertical parts of the throttle linkage assembly using a small prybar or very large screwdriver toward the rear of the car enough to get the adjustment you want. I am talking about bending the parts that bolt to the back of the motor and go up to the linkage rod that runs horizontal behind the motor. That changes the distance from the linkage carrier to the carburetor, and thus, the linkage stop points.

[Big hammer]

No the back of your motors, there are two oil holes in the linkage that seldom get oiled. If that doesn’t work the long arm before the connecting arm to the carburetor needs to be bent. I needed to bend that arm after changing to a Zenith carb!
FYI when removing or installing a motor remove the linkage on the back of your motors before you damage it, it has happened to me :-(

[burner31]

Don't bend anything!
You have a '31 two-tooth, your colunm may need some adjustment...thats all.
Does your spark level go to the forward and aft stop on the distributor housing?
Check that, people always check the forward movement but they sledom check the aft movement.
If thats the case just loosen the two screws on the support cap under the dash and then the colunm clamp above the steering box, twist your colunm to adjust, once there, tighten it all back down.
But bending things does not fix much

[Gary WA]

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throttle linkage on rear of motor ? and do you have the correct length rod to carb? Throttle Linkage needs work

[Benson]

Did you use the same throttle linkage from original engine? If not linkage on "new" might be all bent up.


When swapping linkage do not lose the 2 "U shaped" brass shims on two upper bolts on the flywheel housing!

One thing for sure ... many times linkage gets bent removing engine.

If you have one that works remove it before taking engine out!

[oldman - NorCal]

You know, about a month ago I came upon a similar post regarding the hand throttle linkage being bent and preventing the throttle linkage to the carb not being the correct length. I promptly went to the garage and with a little force and big screwdriver jumped into action. I came to realize that for 40 years I have been bending my throttle linkage into all sorts weird shapes to get the right setup and get the carburetor to idle down. This site is really great and, you can teach an old dog new tricks. Thanks to everyone that contributes to this site and shares your vast store of information.

[aermotor]

This thread is a perfect example of everyone giving it their best shot yet no response from the O.P. Kinda tough to learn without knowing the outcome.

John

[Don Turley]

Originally Posted by aermotor

This thread is a perfect example of everyone giving it their best shot yet no response from the O.P. Kinda tough to learn without knowing the outcome.

John

The original post was from England. It has only been about 8 hours since his inquiry. Give him a little time.

[Zephyr4]

I'm having a busy time at the moment, so I might be a bit slow with replying to things.

Thanks for all of the responses, it's got me looking at a few things.

So the spark advance/retard can go to the limits on the slot in the lower part of the dizzy cap. However, if I take the cap off, it can go a little further in both directions, so I'm thinking there may be something in rotating the column a little.

The throttle linkage assembly is the one from the car, not the engine I think. The one from the engine I guess got removed when the engine was pulled from the original car. The one I've fitted is greased and oiled and free moving.

I've also had a look at these: https://www.brattons.com/3-piece-control-rod-set.html and see that the throttle rod is advertised as 6". Mine appears to be 6 3/16" total length when installed. The rod to the carb is the advertised 10 3/4". So maybe that's a factor too.

I'll have a look through the spares I have to see if there are any other rods closer to 6" and I'll try rotating the column to see if that helps. Then I'll starting bending stuff!

Thanks again.

[aermotor]

Sorry, I didn't notice England. Yes, try rotating the column first.

John

[johnbuckley]

If you get fed up of bending, twisting, rotating, things then this little gadget is a tidy solution sometimes .( from Synders catalog)