Ryan's M3 medium

[Bob Moseley (RIP)]

Hi Ryan - an old proven method of freeing rusted parts is to put them in a bath of molasses. It is a slow process but you will know if it is working if you get a lot of penecillin on the surface. Your main problem will be to get the tracks into some sort of container, but trust me, it will work. If you go back to my thread on electrolysis derusting in 2004, you will see several posts on molasses. There is also plenty of advice on Google.

Bob

[anthony urek]

Yep will slip right off the truck on all that molasses

[tankbarrell]

Unless the tracks have been changed to a non-original type, all of the Grant and Sherman track, whether rubber faced or steel use pins with rubber doughnuts pressed into the links. Therefore, they cannot seize as they do not move beyond the rubber limit to start with and if you soak them in diesel, it will eventyally destroy the rubber.

If it is original style track, it is likely the brakes are stuck.

[Ryan]

Once again thanks for the advice guys.
Adrian, here's a couple of pics of the tracks. I'm pretty sure that they are original. The tank I'm now told has been sitting in the same spot for between 10 and 20 years.
Bob I'm not sure I'll find a bucket big enough to fit the tank in.

[lynx42]

Nice tracks Ryan, looks like fairly good rubber on the wheels too. Well done. Does it have an engine fitted?
Regards Rick.

[Ryan]

Hi Rick, no it doesn't have an engine fitted. Just a big, stuck garden ornament.

[tankbarrell]

Ryan, that's T49 track and it will not be seized. It is, as is all other M3 track, rubber bushed so it will be a brake or transmission issue.

[cantankrs]

Well Adrian's right (as usual) - the track frames for that style of track still have rubber donuts in the guts, so your problem moving it is not seized tracks - if it were a Matilda or Valentine or Bren Carrier then yes they rust up.

If anything in the bull gears or tranny is jammed then you may have to split the track front and rear and anchor the top track in place so it doesn't damage anyone and tow the hull onto a float. Then try and drag the remaining two bits of track up underneath the hull onto the floor of the float so you can get it home. Splitting it after all these years is the next problem as you probably don't want to cut it cos then you need some bits to replace it. Phill and I know a chap who winched (dragged) a Grant hull onto a float and then had to get it off later. Heavy metal can slide scarily easily on a steel deck but the owner of the float may not be interested.

Can you post some pics of what's left inside both engine bays and the rear of the hulls at some point so we can try and help identify what engines they probably had?

As far as I can gather, depending on the manufacturer there may be a number stamped into the top edge of the towing eyes at front and rear of the hull. I've read that only 1 in about 3 manufacturers did this. Since many of these did a lot of towing in private use the towing eyes may instead be mutilated. If the diff housing has been swapped out then the numbers would be different front and rear.

If either of the hulls is a Petrol radial then it has twin doors or at least a square opening you can step into at the rear. Look centre top edge of that back lower hull corner casting and there might be a number stamped into it with letter punches - I'd be interested to know what the number is cos I'm trying to find if it's a part number or whether some hulls had their number stamped there.

Alex

[Bob Moseley (RIP)]

Hi Ryan - firstly the seized track. Depending on how much room you have on your property, you could dig a tranch to accomodate the track. Line the trench with heavy duty plastic sheeting and then immerse the track in the molasses solution. Ensure the plastic wraps across the top of the solution to stop it evaporating. It would be better with the tracks off the tank but you could do the same if they were still fitted. You would need to dig the trenches underneath the tank and then lower it into the trench. This however would only do the lower portion of the tracks.

Secondly the rubber donuts. If you need new ones, the industrial rubber factory I get my Carrier wheels re-rubbered should be able to manufacture new ones providing they obtain a template. The only problem I envisage is whether the donuts were inserted between the links when the tracks were assembled or whether they could be inserted after market.

Bob

[D Ellery]

Hi Ryan. Awesome project you have there. I visited John Belfields Museum early 2000 and fell in love with his M3 as with all the M3 parts out the back, actually I think I spent more time out the back climbing over all the rusty steel than inside the museum. My great uncle trained on these in Egypt prior to the Italian campaign so please continue with the posts and plenty of pics when you can. Cheers David.

[tankbarrell]

Originally Posted by Bob Moseley

Secondly the rubber donuts. If you need new ones, the industrial rubber factory I get my Carrier wheels re-rubbered should be able to manufacture new ones providing they obtain a template. The only problem I envisage is whether the donuts were inserted between the links when the tracks were assembled or whether they could be inserted after market.

Bob

The pins are pressed into the links after the rings are moulded onto them. However, at the risk of becoming repetative, it's all academic as the track will not be seized......

[Ryan]

Thanks Adrian for the ID.
Alex, thanks for the tips, will post your pics when I get it home.
Bob, thanks for the idea, hoping it's just the brakes.
David, plenty of pics will come, I enjoy posting them as much as I enjoy seeing other peoples pics.

[Ganmain Tony]

Mein Gott!! Ryan ..... that is a project and a half. Very best of luck with it and hope it brings you lots of joy at the end of the frustrating bits.

Looking forward to this thread as regular entertainment for the next 4 to 5 years.

[anthony urek]

Looking forward to this thread as regular entertainment for the next 4 to 5 years.

Now thats funny! But True!

[Ryan]

Originally Posted by ganmain tony

mein gott!! Ryan ..... That is a project and a half. Very best of luck with it and hope it brings you lots of joy at the end of the frustrating bits.

Looking forward to this thread as regular entertainment for the next 4 to 5 years.

........lol!

[Ryan]

Grant no.2 arrived today on the back of a truck from NSW ( border raid complete ) and a crane was brought in to lift it off as it was thought at the time to be immobile.

[Ryan]

Some of the links are tight and kinked and combined with it not being able to be moved by two 120hp tractors where it had been sitting lead to the false seized belief. The Grant it turned out had been sitting in its spot for up to 25 years. The owner spoke of it being a training tank for the Army before it was purchased by a neighbouring farmer post war.
A crane was used to load the tank in NSW and a further crane organised for my end.

[Ryan]

Here are some shots for the brains trust.
What engine/s where fitted to this type of hull?
The tank number as found on the front and rear lifting hooks is T465.
Some interesting writing was also found on the inside of the hull, perhaps factory inscriptions?

[Ryan]

So once everybody was gone I fired up my No.1 Grant, hooked up some chains and rolled the No.2 Grant on its tracks with ease, shifting 25 year old dirt and rust. So my hip pocket is a bit lighter than it should be. But all's well that ends well.

[Ryan]

It weighs 17tons.
The steering gear is stuck with one lever oxy'd off halfway up.
One return roller has been oxy'd off.
Some of the road wheels have the rubber worn off.
Some of the bogies have holes cut into them for fitment of bolts. A dozer blade had been fitted to it. I don't believe it to be an Army one though. It's still up in NSW.
And there's a scratch on the bumper.

[Luke R]

G'day Ryan
Looks looks like a diesel Grant (M3A5)?
twin supercharged GM6-71s.
Very nice find.

[tankbarrell]

Originally Posted by Luke R

G'day Ryan
Looks looks like a diesel Grant (M3A5)?
twin supercharged GM6-71s.
Very nice find.

Definately, the muffler casting cut out is unmistakeable.

[cantankrs]

Yep, I agree. The pair of engine floor inspection plates seem to be present too. All very nice. That weight is interesting to know. Course the cone shaped dome on the back of the gearbox is the handbrake. The tailshaft with the sprockets welded to it has the right looking unijoint for Grant too - I think its Mack, like the gearbox, whereas the diff/final drive assy probably has a Chrysler plate on it? Any track joints that are 'kinked the wrong way' are known as 'dead' - I think it just means the track pin with the rubber donuts has managed to twist in the tube that forms the track frame (don't know if the donuts shear or if they slip in the tube, or both). I don't think you can go very fast with dead shoes - I presume there's a big risk of a track breaking and high risk to anyone nearby along with colateral damage. I have a Stuart manual that shows the track pins with donuts being pressed into the track frame under high pressure after being dunked in castor oil (caster oil being non-harmful to rubber - I think it's what brake part grease is made from). The pins have the flats machined in them for the connector wedges and thus the pins are held by a jig in a certain orientation so when they're pressed into the track frame they are slightly angled and when the track is assembled it has a tendency to curl inwards thus creating 'live track'. That type of steel 'pad' consists of two halves, outer and inner. Outer has the 'tread' and both may be plug welded together. Also that steel track probably has 1/16 or 1/8" (I can't remember) thicker diameter pins than the rubber track on your first M3 Medium. The sprockets are the same so the connectors are bored out I think.

Regards

Alex

[anthony urek]

Ripper pics Ryno, job well done. What is the heaviest the crane can lift?
Just shows you how effective tracks are for grip. But watching a WWII doco last night they showed a Sherman sliding down a road sideways on an icey day.

[Bob Moseley (RIP)]

OH NO!! Throw the tank away. That is as bad as having a full ashtray in a car. The tank is stuffed.

Bob

[Ganmain Tony]

Well done with the tracks old boy..... amazing what can be achieved by just saying 'bugger it' and adhering to Murphy's law....

"If it jams..force it. If it breaks, it needed replacing anyway"

Have you got any pictures of the current donk and transmission set up in the one that goes??

Just very interested to have a look..

Has anyone got any pictures of what was originally in these beasts??

Twin GM and Radial set ups??

One last question - did the Australian Sentinel use the same Chassis set up as the M3??

[cantankrs]

Anthony Urek's current thread has the picture below (the last pic) posted by 'Roy206' of a 6046 power pack. Also in the thread is the same chap's link to their running 6046
Note that there were other combinations of GM 6-71's such as a few pics I've gathered from eBay over the years of GM powerpack configurations for various applications.
Also, here in Western Australia is a fairly legendary primemover or tractor truck built after the war to haul iron ore to port named the Rhodes Ridley and it has a twin powerpack from an M3 Medium along with a gearbox and I think they used the crown wheels and pinions in specially cast diff housings. Click the link to visit their website.
And for Tony regarding the Sentinel, while it was based on M3 Medium drivetrain and tracks, the AC1 employed 3 x Cadillac SideValve V8's. Two other engine configurations tested was the 3 x V8 blocks mounted onto a welded steel common central case something like the Chrysler Multibank; and then 3 x Gypsy Major (I think it was) aircooled inline aero engines in the intial clover leaf layout. The thing was that Australia seemed to not have the machinetools to produce helical gears so they developed a straight-cut geared variation of the M3 box. Bradford Kendal I believe cast the hull and diff housings and turret. Only recently I found that the floor appears to be 3 x flat steel plates bolted into the hull casting, for each the driving, fighting and engine compartments - happy to hear more about this from anyone..?
I note that the French Somua S35 appears to have been a major earlier achievement in being cast as a 2 piece lower hull, 2 longitudinal plate floors, 2 piece upper hull and turret. While BK took the Sentinal's castings further by employing one main casting for the hull (except the diff housing and floors as noted).
Alex

[Ryan]

Hi Tony, the cranes max lift was 28tons according to its hook.

Cheers Bob, thought I'd throw a curly one in.

Ganmain T, here's some pics of the set up. It's a MAN truck engine of 15.2lt, v8 and 300hp. And hey.....you know of a Sentinel do ya??? Check out my Sentinel thread here: http://www.mapleleafup.net/forums/sh...ad.php?t=11517

And cheers for the ID Luke, Adrain and Alex. Here's a close up of one of the suspect track links too.

[Ganmain Tony]

Vast knowledge Ryan that comes from Wikipedia.....

Very interested in all this stuff - always have been. Built all the models when I was a kid, etc etc...

Great powerplant!! Youve just gotta move it to the back...

Would be an awesome start to building a replica Sentinel. They look manificent in pictures with the 17 pounder.

Speculation of course but I reckon they would've done a better job than the Sherman.

Figure wise, on paper they add up. Low profile, sloped armour, very quick (for the day) well armed (with the 17 pounder). The yanks couldve tooled up for this design.... surely.

I vote for building replica Sentinel - but then, it aint my money.

[Ryan]

Tony, a sentinel replica sounds like fun, why not, poeple do panzer replicas on stranger things. Still hoping for a real one. My other half is still reminding me that I should have bought the AC3 sentinel at the john belfield tank auction in 2006. Selling price, $22,500. Yeah. Live and learn.
From your original post I thought you were hinting at the possibility of another surviving Sentinel up your way, hense my " do you know of one". They have to be out there.