Info needed: F60S progress - accelerator linkage

[Alastair Thomas]

My brothers and I are making progress on the rebuild of our F60S LAAT.
Last week end we fitted the driver's toe board and the accelerator linkage crank forward of it.
Is the link from there to the carburettor just a straight rod or is it kinked in any way? Frustratingly all the photographs I have found here either show engines missing this link or are taken from the other side.

[Jacques Reed]

Hi Alastair,

As per attached photo the rod in question has a slight bend in it to clear the PCV valve if fitted. Mine was bent like that originally so I assume it was made that way but it could have been done later.

Cheers,

[Tony Smith]

Originally Posted by Alastair Thomas

Last week end we fitted the driver's toe board and the accelerator linkage crank forward of it.
Is the link from there to the carburettor just a straight rod or is it kinked in any way?

Note that there is another crank that is mounted above the two water pumps to reverse the pull of the rods. There is a rod that goes from the "driver's toe board crank" to the "Water pump crank", and then another rod that goes from the "water pump crank" to the carburettor lever (as pictured by Jacques).

Also, there are two balls on the carburettor lever, the lower one is for the linkage to the pedal, the upper one is for the manual throttle "organ stop" located on the transmission cover.

[Jacques Reed]

Originally Posted by Tony Smith

Also, there are two balls on the carburettor lever, the lower one is for the linkage to the pedal, the upper one is for the manual throttle "organ stop" located on the transmission cover.

Hi Tony,

Just a slight correction. I think the upper one on the right side is for the choke rod. (The choke is the device anyone under 30 years old has never seen or knows how to use!)

The lower one on the throttle shaft, left side is the manual throttle rod to the transmission cover.

Cheers,

[Jacques Reed]

Originally Posted by Tony Smith

Note that there is another crank that is mounted above the two water pumps to reverse the pull of the rods. There is a rod that goes from the "driver's toe board crank" to the "Water pump crank", and then another rod that goes from the "water pump crank" to the carburettor lever (as pictured by Jacques).

Hi Alastair,

As Tony mentioned, here is the crank mounted on the water pumps. A short rod, 3" long, connects the toe board crank ball to the lower ball on this crank.

Cheers,

[Alastair Thomas]

Thanks everyone for the information. I have been looking at the wrong page for the answer hence my late acknowledgement.
The picture gives me a problem however. Nearby here is a F60S LAAT and I took the opportunity to look at its linkage and the upper arm on the cross link is much shorter than the one in the photo. This seems to me to be logical as the travel at the carburetter is limited to about one and a half inches so such a long arm as is shown would surely risk bending the carb linkage.
I have been working on similar triangles and lengths of arm from the pedal onwards and this would seem to confirm my impression.
I might add that the truck is in "well used" state and that I can see that a number of things are non-original.

[Jacques Reed]

Hi Alastair,

As per attached photo: The arm in question has to be fairly long to clear the HT lead conduit. Any shorter and it would foul it.

Travel of the throttle plate arm can be limited to prevent bending anything by a bolt that screws into the back of the accelerator pedal (this bolt I usually find missing but you can see the tapped hole for it on the backside of any pedal at the top).

It is listed in the parts manual as part No. 20368-S7, Bolt- Accelerator stop, 3/8-16 x 7/8" (3/8 UNC 7/8" long) There is also a nut listed for it as 33927-S2, Nut- Accelerator pedal stop bolt. Surprisingly it is then shown to be 7/16-20 Hex check. Don't think a 7/16" nut will work very well on a 3/8" bolt although I believe I have seen attempts of similar things at times!

Hope this is of some help.

[Tony Smith]

The length of the upper arm from the axis is about the same as the length of the lower arm, so the ball would only move the same amount as the throw of the "Toe board" ball.

[Jacques Reed]

Hi Alastair,

Further to discussion here is the setup I did on a spare accelerator pedal I have. One picture worth a thousand words.

I used a 3/8 UNC x 1" bolt instead of the 7/8" long one as specified. Didn't have a 7/8" long one. The check nut is obviously a 3/8 UNC not a 7/16 UNC as specified in the parts book.

check nuts can also be referred to as half-height nuts which is what I have here.

Also the initial position of the pedal can be set by the adjustment on the pedal rod. Note the half-height check nut on it. Between that adjustment, and the stop bolt, you should be able to do pedal to the metal without bending any of the linkage rods or arms or carby shaft.

Hope this helps.

Cheers,

[Alastair Thomas]

Thanks everyone. I will go ahead and make the necessary links and control the overall motion as you suggest.