New Game CMP Brain Teaser Trivia

[Lynn Eades]

It has to be about moving 1st gear (mainshaft, big. gear) out of the way.
So my guess. You put the trans into 1st gear.

[Keith Webb]

Here's one for those outside Australia to answer (Mike C please hold off for a moment)

Why is the cowl vent on most CMPs found in Australia a different shape to those elsewhere?

[Tony Wheeler]

Here's one for Australian CMP owners, although anyone can have a crack at it:

In what way do chassis siderails produced for Australia differ from all others?

[Phil Waterman]

Hi All

You are getting closer but not quite.

I put a transmission up on the bench today and photographed the relative position of the all gears in each gear range. So once we have an answer I'll post the pictures.

Think about which gear is closes to the filler hole.

Cheers Phil

[Richard Farrant]

Originally Posted by Phil Waterman

Think about which gear is closes to the filler hole.

Reverse gear?

[Tony Wheeler]

Originally Posted by Phil Waterman

Think about which gear is closes to the filler hole.

Having just looked at a Chev gearbox from the outside and discovered the filler plug is on the rear face of the housing, offset well to the RHS and located on a bulge in the casting, the answer has to be reverse gear. That is, reverse idler gear would blank off the filler hole in neutral. Quite poor design IMO.

[Howard]

Originally Posted by Tony Wheeler

Here's one for Australian CMP owners, although anyone can have a crack at it:
In what way do chassis siderails produced for Australia differ from all others?

ALL chassis lengths, Tony? Or just, say, long WB's??
H

[Tony Wheeler]

Originally Posted by Howard

ALL chassis lengths, Tony? Or just, say, long WB's??
H

Yes it applies to all chassis lengths Howard.

[Grant Bowker]

Originally Posted by Tony Wheeler

In what way do chassis siderails produced for Australia differ from all others?

Is the precise wording a clue? In other words, is there a difference in rails made in Canada for Australian use compared to those for Canadian or British use? Is the difference you are seeking common to Ford and Chev?

[Phil Waterman]

Hi Guys

Richard, got it first and Tony got it second. You win less gear lube dribbling down your arm the next time you have to add lube to your Chevy transmission.

Picture of Spare Transmission
Transmission 002.jpg
Transmission in Neutral
Neutral Trans 005.jpg Neutral Trans 006.jpg Neutral Trans 008.jpg
Transmission in 3rd gear (the spacing is the same for all forward gears)
3rd Gear Trans 019.jpg

See the next post for the difference with transmission in Reverse.

[Phil Waterman]

Hi Guys

Now for the difference in Reverse

Reverse Trans 012.jpg Reverse Trans 014.jpg Reverse Trans 013.jpg

As you can see in the middle picture above there is about an inch more clearance in side the box with transmission in reverse.

As the plug is located in a position almost impossible to actually look in on the truck, I remove the plug an insert a finger (clean of course) and crock the first joint to check the level.

Now for curiosity here is the top cover with all the forks set for Neutral I have a copy of this picture and one looking down into the transmission with all the gears in the neutral position as reference in the shop.

HUP Neutal Top Trans.jpg

The last picture is transmission tick tac toe for where are the different forks positioned for what gear.

Shift Fork Possition1.jpg

Note of explanation: The reason for all the grease on the gears, this is my spare transmission that have repaired after breaking a tooth. As this one is in storage want to really protect it from rust so I coated everything inside in a heavy layer of grease. Then sealed all the opening as much as possible.

Story of breaking the tooth http://www.mapleleafup.net/forums/sh...ighlight=tooth


Now for you Ford guys is there one gear better than another for checking the lube?

To sum up

What gear should you put a Chevy CMP to check the lube level in the transmission?

Answer

Reverse as this moves the gear closest to the lube fill plug away by an inch. Allowing for easier checking and easier adding of lube if needed.

Side point don't over fill it just makes them leak more.

Cheers Phil

[Richard Farrant]

Well Phil,
I know the box is virtually identical to that used on the WW2 Bedford trucks, but had forgotten how Chev put the level plug at the back. The British arm of GM had the level plug in the side so none of these dramas.

Bedford also redesigned the Chev 216 into the Bedford 28hp, which had full pressure lubrication to mains and big ends along with replaceable shell bearings ...... oh and no fibre cam gear either. All this before the first Chev CMP's went into production too!

[Tony Wheeler]

Originally Posted by Phil Waterman

Now for you Ford guys is there one gear better than another for checking the lube?

No such issues Phil, the filler plug is on the side of the box, well clear of the gears. It's also angled downwards about 45 degrees, so your finger could reach down further to check the level. All very considerate of Ford, unlike the dizzy!

Interesting to compare the two gearboxes, I've never looked inside a Chev box. The Ford one seen here is in 3rd gear. Reverse idler and selector fork can be seen top left. It's on a half length shaft, unlike the full length Chev one. As you can see Phil I couldn't quite match your maintenance standards!

TONY6313 - Copy - Copy.jpg

[Tony Wheeler]

Originally Posted by Grant Bowker

In other words, is there a difference in rails made in Canada for Australian use compared to those for Canadian or British use? Is the difference you are seeking common to Ford and Chev?

Yes to both questions Grant. It's a tough question if you're not familiar with Australian CMPs. Even then it's pretty tough!

[Richard Farrant]

Originally Posted by Tony Wheeler

Yes to both questions Grant. It's a tough question if you're not familiar with Australian CMPs. Even then it's pretty tough!

Hi Tony,
Would this difference also involve those CMP's sent to India as well? I am aware the Indian ones had heavier steering boxes so maybe the chassis was heavier / thicker?

Richard

[Tony Wheeler]

Originally Posted by Richard Farrant

Would this difference also involve those CMP's sent to India as well? I am aware the Indian ones had heavier steering boxes so maybe the chassis was heavier / thicker?

Sorry Richard, I missed your query earlier. No, it's not related to the steering box. Hint: try the other end of the chassis!

You raise an interesting question though. CMP chassis deliveries to India and Australia differed from Canadian production, in that neither country received the heavy duty axles and steering box until much later in the war. I've never really understood why this should be so. Presumably they were prioritized for Canadian production initially, but that doesn't explain why it took years to switch production from light duty components to heavy duty components. It seems to me there must be some other reason for persisting with light duty components for these particular exports, but I can't imagine what it could be. Does anyone else have any clues...?

As far as the siderails are concerned - to the best of my knowledge there's no difference between siderails on early production chassis (ie. light duty components) and late production chassis (ie. heavy duty components). I believe the heavy duty Chev steering box is directly interchangeable, and the steering box on Fords is upgradeable by changing the RHF spring hanger, which is designed to be interchangeable without drilling new holes. The only other change made was to the F60S/L chassis, which was strengthened in the midsection. That is, externally fitted reinforcement plates, and extension of the inner skin rearwards by approx 2 feet. None of this additional reinforcement was done on the Chev chassis as the siderails are much beefier than Fords.

[Howard]

Originally Posted by Keith Webb

Here's one for those outside Australia to answer (Mike C please hold off for a moment)
Why is the cowl vent on most CMPs found in Australia a different shape to those elsewhere?

Is Ganmain counted as outside Australia?
No?

[Grant Bowker]

Originally Posted by Keith Webb

Why is the cowl vent on most CMPs found in Australia a different shape to those elsewhere?

A. They were already tooled up for that shape for another model (but I've no idea what model that might be)
B. Just to be different
C. To provide an identifying point for restorers 70 years in the future.

[Keith Webb]

Originally Posted by Grant Bowker

A. They were already tooled up for that shape for another model (but I've no idea what model that might be)
B. Just to be different
C. To provide an identifying point for restorers 70 years in the future.

Yes you are correct there Grant... and seeing Mike thinks the question is unfair perhaps I'll post a supplementary one...

What approximate percentage of the

A Chevrolet cab 13

and

B Ford cab 13 was locally made in Australia?