How To: Ford CMP "Blitz" miscellany

[Jacques Reed]

Hi Hanno,

I cannot thank you enough for the photos and length information. After 30 years climbing over relics, not finding a single speedometer cable on any truck, I finally have the right information.

*C29Q 17262 is listed in my F-15A parts list as the shaft for the "new design" cab, i.e. Cab 13 I would assume.

I notice you have the vertical entry cable at the transfer case speedometer gear. Mine is the later horizontal. I will check out my truck and see if it adds any extra distance to the length where it penetrates the crossmember. At least I got that right.

I have determined for a round speedometer that the distance from the speedometer ferule end to the transfer case ferule end is 35mm-41mm less than the shaft depending on whether the transfer case shaft end has a shoulder on it or not. (See attached). If no shoulder on the tip the shaft goes 6mm further into the driven gear and 6mm less into the speedometer. That may be acceptable, but I prefer full engagement of the shaft in the speedometer. That makes the casing length about 83-1/2" (2121 mm). It may, however, be slightly different for a Ford commercial speedometer due to different end nuts at the speedometer.

Knowing this I can now get my cable shortened.

Many thanks again for your help.

Cheers,

[Hanno Spoelstra]

Originally Posted by Jacques Reed

I cannot thank you enough for the photos and length information. After 30 years climbing over relics, not finding a single speedometer cable on any truck, I finally have the right information.

Hi Jacques, happy to be of help. It is the least I could do in return for the wealth of information you post on here.

Interesting note about not finding a speedometer cable on any truck in Australia. Either they were in short supply so every Blitz was stripped off it, or seeing most of the Blitz' are used as paddock bashers, tree sniggers or whatever you call them, there was no need for a speedometer!

[Jacques Reed]

Originally Posted by Hanno Spoelstra

Hi Jacques, happy to be of help. It is the least I could do in return for the wealth of information you post on here.

Interesting note about not finding a speedometer cable on any truck in Australia. Either they were in short supply so every Blitz was stripped off it, or seeing most of the Blitz' are used as paddock bashers, tree sniggers or whatever you call them, there was no need for a speedometer!

Hi Hanno,

I think that is it, also maybe removed to prevent fouling during an engine change and never put back. Also in the case of F-15's and F-15A's you can add missing handbrake cables going to the backing plates to prevent fouling on stumps. Hydraulic brake lines also go missing. Bolt cutters seem to be the weapon of choice in all cases.

Thanks. As researchers say, go to the source. Nothing beats measuring and sighting an original, be it a part or a document.

Cheers,

[John Mackie]

Hullo Jaques, I have always enjoyed reading your posts. the informaion available on MLu is terific.
I have just aquired a F15 A, it was a bushfire truck out here in the western riverina so is a bit knocked about but mot a lot of rust. Because there was no room in my shed it has gone to my son's. he had it running in less than 24 hours.
it has been fitted with a 2 speed transfer case and a trensmission handbrake so I do not have to chase up handbrake cables to the rear wheels.
I have been following the discussion about spedo. cables and realise I will havs the same headakes. In your photos you show a cable end with what I would call a key / keyway set up, I have never seen Ford use these. Detroit diesel and maybee GM used them. What are they from?
I hope John will put information up about his progress on MLU

[Jacques Reed]

Hi John,

The keyway end or tang end, as some manufacturers call them, at the transfer case seems to be another thing unique to these vehicles compared to standard Ford vehicles. I don't know why they use them. Perhaps the transfer cases are outside supply to Ford so that is what they are given.

Civilian Ford car and truck speedometers of course are driven from the transmission as there is no transfer case.

All civilian Fords use a driven speedometer gear with a square hole for the shaft. The shaft is flattened to a 0.104" square to go into this hole, same as the speedometer end. This is why no cable from any of the old Ford parts suppliers will work on a Ford CMP except maybe an F-15. They have a standard 20 tooth driven gear with a square hole, which is located on the rear transmission mount as used on 4 x 2 four speed transmissions.

Clark Brothers Instruments catalogue, available online, show some of the fittings used on speedometer cables. The nuts have not changed since WW2 and are still available. Male 3/4-20 UNEF at the commercial speedometer and Female 7/8-18 at the transfer case. Likewise the 0.203" lower tang tip which looks identical to mine and is the same dimensions. I think your connection to Detroit Diesel makes a lot of sense as Clark Brothers supply a lot of instrumentation for the big rigs. These tang tips obviously are used by some of them.
Don't know availability here of their products but at least it is a reference if someone has to talk to a cable manufacturer.

Hope this is of some interest and help.

Cheers,

[Grant Bowker]

Speedometer cable at transfer case:
1. I don't know whether Ford and Chevrolet use identical cable tips at the transfer case.
2. If they are the same, Phil Waterman put Chevrolet measurements on his web site at http://www.canadianmilitarypattern.c...ge%20Notes.htm
3. From memory (not to be trusted 100%) I think Clark Brothers Instruments http://www.clarkbrothers.net/catalogs.html had similar tips but not absolutely identical to Chevrolet. My memory is that the precise cable and sheath weren't obviously available but I may not have looked hard enough....



A couple of days ago I made up a dummy to see whether the sheet metal guide at the transfer case could be replicated on a bead roller. No photos at this time but the summary is "exact to the nth degree" - no, but functional should be possible.

[Lynn Eades]

The riveted carriers use a drive like that. The cable nuts (female) are brass thread, so probably British origin. May be that kind of drive is as well?

[Jacques Reed]

Originally Posted by Grant Bowker

Speedometer cable at transfer case:
1. I don't know whether Ford and Chevrolet use identical cable tips at the transfer case.
2. If they are the same, Phil Waterman put Chevrolet measurements on his web site at http://www.canadianmilitarypattern.c...ge%20Notes.htm
3. From memory (not to be trusted 100%) I think Clark Brothers Instruments http://www.clarkbrothers.net/catalogs.html had similar tips but not absolutely identical to Chevrolet. My memory is that the precise cable and sheath weren't obviously available but I may not have looked hard enough....



A couple of days ago I made up a dummy to see whether the sheet metal guide at the transfer case could be replicated on a bead roller. No photos at this time but the summary is "exact to the nth degree" - no, but functional should be possible.

Hi Grant,

I had a look at Phil's drawing and my dimensions are the same where it connects to the driven gear: tip diameter = 0.203", height of tang = 0.040"
Overall length is different. Mine is shorter at 1.20" (nominal 1-3/16" same as Clark Bros tip J-2) Likewise my shoulder position is the same as J-2, 3/4".
There is also no O-ring notch on mine or tip J-2.
My shoulderless tip has the same tip diameter and tang height.
Both tips were pulled out of Ford transfer cases that looked like they hadn't been touched since WW2. It has just dawned on me. I think the J-2 type came from a two speed transfer case and I think it had a large diameter casing. I replaced my 2 speed with the single speed in keeping with a F-15A. The shoulderless type definitely came out of a single speed case and had a remnant or 1/4" diameter casing on the ferule.

The only bare steel outer casing Clark Brothers stock is bulk 0.25" OD which is the Ford commercial and F-15, F-15A size. Perhaps Ford used a larger casing on their two speed transfer cases too?
Covered sizes may be the same as Chev, without the covering, but I will leave that to the Chev guys to determine.

Cheers,