Jump to content
monty2

restoration of a valentine MK5 tank started

Recommended Posts

This week the Engine will go into the engine rebuilder for some specialist work. It is an original Valentine Tank engine. The engine is a GM Detroit 671 model 6004 . We have NOS head / liners / camshaft / new bearings etc for this rebuild, further updates will follow this, from the Tank Factory.

DSCF4764.jpg

DSCF4780.jpg

DSCF4771.jpg

Share this post


Link to post
Share on other sites

After completing the strip out of the other gearboxes , we now have enough good shafts. It was mainly the Mainshaft that

gets the damage to the spline, when the big sliding gear 1st/reverse is engaged, if the Tank is not stopped properly it will start wearing the spline away on this shaft, so we selected a shaft with no wear. Pictures show all the gears required in the main gearbox and mainshaft in the vice with 2nd gear being fitted, that also contains 156 little needle rollers , that have to be fitted without losing any! Next is sychro hub and 3rd gear next with a further 156 needle rollers and then 5 gear with 134 needle rollers. Cheers from The Tank Factory.

DSCF4759.jpg

DSCF4794.jpg

DSCF4800.jpg

DSCF4803.jpg

DSCF4806.jpg

DSCF4808.jpg

DSCF4811.jpg

Share this post


Link to post
Share on other sites

While we are waiting on gearbox bearings to turn up from the USA, and I am getting all the gearbox gaskets laser cut for accuracy ,and the engine is at the machinists for specialist work,

I have made a gig up for compressing the main suspension springs.

I have dismantle about 20 to get enough good inner shock absorber shafts for the Tank. It requires 4 in total. The inner shafts are chromed and can get rust spots on the chrome, which is not too good.

This Chrome shaft only slides through a bronze housing, and not through any seals, when the suspension is in motion. All the hydraulic dampening for the spring and sealing work is done by another inner shaft, to this outer one. Cheers from The Tank Factory.

DSCF4265.jpg

DSCF4357.jpg

DSCF4356.jpg

Share this post


Link to post
Share on other sites

Following on from last week, we have all the bearings arrived from the States and we have processed the gear case and have started on the install of the lay shaft and main shaft. The second pic shows the spline to the L/H side that usually gets the most damage from the 1st/Reverse gear meshing onto it . Third photo shows reverse idler installed , after the Lay shaft . Still waiting on the laser to spit out the gaskets, so that will be next week. Cheers from The Tank Factory.

DSCF4813.jpg

DSCF4816.jpg

DSCF4817.jpg

Share this post


Link to post
Share on other sites

Next on the production line are the final drives. There is a L/H and R/H one, 460kg's each. The difference between the different sides is that the level plug is slightly below centre line, so it is possible to install these upside down if you do not know what you are looking at. The technical term for these units are: Compound fixed epicyclic reduction gear giving 10.214 to 1.

This is why, if you have ever noticed a Valentine speeding past, that the Brake drum is spinning heaps faster than the sprocket. I do not know of any other Tanks with this oddity. I would guess it gave the brakes inside the large outer drum more efficiency , and they do work extremely well .Pictures show striping of the L/H unit. It turned out to be a NOS one as it still had the part numbers stencilled on the outer casing , and there is absolutely no signs of wear on the teeth, the machine marks are still there. The R/H one we started to strip , would not release it's brake drum, so rather than fight it, it can go back in the store and I will select another one. The procedure for removing the brake drum, is you undo the outside ring of bolts and then screw in 3 draw bolts, that push off the inner hub face forcing the drum off the shoes. Will replace all seals with new ones as even though the units can be NOS, the old leather seals become too hard and will fail. There are 4 large seals in total per unit. Cheers from The Tank Factory.

DSCF4818.jpg

DSCF4821.jpg

DSCF4823.jpg

DSCF4824.jpg

Share this post


Link to post
Share on other sites

Thank for posting such detailed photos Andrew. Those final drives look rather complicated.

Share this post


Link to post
Share on other sites

the quality and complexity of manufacturing is really impressive , even if you don't consider that's it's 1930's manufacturing technology.

 

Will replace all seals with new ones as even though the units can be NOS, the old leather seals become too hard and will fail. There are 4 large seals in total per unit. Cheers from The Tank Factory.
are you able to source modern rubber/polymer cup seals or do you have to put the leather ones back in?

I had a hydraulic piston on a vertical saw in my shop from the late 1970's and was surprised to find a leather seal inside after it failed. They used "cow parts" in machinery for a very longtime

 

Next on the production line are the final drives. There is a L/H and R/H one, 460kg's each. The difference between the different sides is that the level plug is slightly below centre line, so it is possible to install these upside down if you do not know what you are looking at.
so if you reversed them the fill plug & oil level would be too low ? definitely a bad thing

Share this post


Link to post
Share on other sites

are you able to source modern rubber/polymer cup seals or do you have to put the leather ones back in?

I had a hydraulic piston on a vertical saw in my shop from the late 1970's and was surprised to find a leather seal inside after it failed. They used "cow parts" in machinery for a very longtime

 

 

 

Nothing wrong with leather lip seals, more durable in certain applications than nitrile. I avoid old stock ones though, as they have usually dried out and shrunk, they never recover. Always good in applications involving gear oil and if they are kept soaked in oil, they can be superior to nitrile or similar as once the knife edge lip on a modern seal is damaged they will weep whereas leather seals over a larger contact area. Just doing a major restoration now and had a stack of metal cased leather seals made, so still available.

Edited by Richard Farrant
spelling

Share this post


Link to post
Share on other sites

Leather seals are great , in certain applications, but from MY experience most of our MV vehicles do sit around a lot so if seal surfaces are good, the rubber seal wins every time. Leather seals need to be nice and soft and be rotated regularly, in order that leeking does not start, just MY humble opinion, Cheers.

Share this post


Link to post
Share on other sites

Have been away for a week or so, on a "pickin " trip for parts , so we are just getting back into it. The final drives have been split apart and we have all the new seals at hand. We have stripped a few extra final drives as one of the centre brake hub shafts was not up to spec on an oil seal surface, so this will be replaced. Also some better brake components were needed from some of the other ones, even though there are NOS parts, just the time in storage can damage parts. One picture shows the shoes, the pads have all been taken off and are getting new linings and rivets. There are 4 per side, all the same. The drums will get a minimal machine up on the inside face to make sure all is true, and also the shoes will be checked for the radius. All the actuating mechanisms move mechanically by wedges , etc, so there are no seals to deal with in those units. I picked up some of the laser cut gaskets for the gearbox, but there are still a few more coming this week, so will show the completed box when these arrive, Cheers from The Tank Factory.

DSCF4871.jpg

DSCF4872.jpg

DSCF4878.jpg

DSCF4877.jpg

Share this post


Link to post
Share on other sites

The 671 Engine has been stripped and has gone through the cleaning tanks. Everything was standard .The crank will get a grind, so we have the new .010 bearings for this, so this will get a new grind in a week or so. We are waiting for the new piston / Liner / ring kits from the USA to turn up soon also. The NOS head has come up great also. Injectors will be sent to the specialist shop this week to be overhauled. Oil pump also gets a new kit. The valves have been dressed and one was found to be slightly bent , so will be replaced. Cheers from The Tank Factory.

DSCF4865.jpg

DSCF4868.jpg

DSCF4861.jpg

DSCF4862.jpg

DSCF4864.jpg

Share this post


Link to post
Share on other sites

Once again ....another staggering restoration :) In awe of how you chaps set about such a gargantuan task and it all steadily comes back together :) Absolute respect to your engineering skills and in some sort of order :)

Share this post


Link to post
Share on other sites

Having received the rest of the Laser cut gaskets back for the gear box, we have commenced the rest of the assembly of it. Pictures show main shaft now in along with oil pump for main input shaft bearing followed by clutch thrust bearing sleeve and then bell housing. Next time work will continue on the Bevel box end which sits directly behind the gearbox and transmits drive to either side. Cheers from The Tank Factory.

DSCF4884.jpg

DSCF4888.jpg

DSCF4883.jpg

DSCF4892.jpg

DSCF4895.jpg

DSCF4896.jpg

Share this post


Link to post
Share on other sites

Work continues on stripping and preparing the brake components that are located on the outer face of the final drive hub, and then encased by the brake drum itself. The last pictures shows the brake actuating gear. This consists of a rod that goes through the centre of the final drive hub and when it moves outward by the Heli-hub control lever and actuating mechanism it transmits the 2 wedges to open the brake units to force the shoes into contact with the drum. Cheers from The Tank Factory.

DSCF4881.jpg

DSCF4880.jpg

DSCF4909.jpg

DSCF4911.jpg

Share this post


Link to post
Share on other sites

Final Drives are now all stripped and the housings are being processed. The second pictures shows the main shaft that goes through the final drive and this outer flange is what the brake drum attaches to. Main housings and sprockets are blasted and given a 2-pot epoxy prime. This is our special brew , that is green in colour, so any wearing of the paint surface when the vehicle is in use would only show green. This paint product was used on our America's Cup yachts, so is tried and tested. Great for a DD Tank! Cheers from The Tank Factory.

DSCF4907.jpg

DSCF4914.jpg

Share this post


Link to post
Share on other sites

I have been offline for some time and have just discovered this thread. As before, you are doing a magnificent job, I am so jealous! You actually have access to spares - wish I did! Any idea of the identity of the beast at all - NZ or UK numbers??

Cheers

John

Share this post


Link to post
Share on other sites

Hi John , I see your DD still featuring often. The T no. is 66784 June 1942, there was also a number 3948 on the plate. It was a Vickers build Tank I think . I am sure you could pull up the contract card for me from Bovy!. After collecting Val parts for 30 years it is quite good to have a very large shed full of spares, you never know when you might need them. Cheers Andrew.

Share this post


Link to post
Share on other sites

The main brake actuating units assembled , ready to be bolted to final drive hubs. Cheers from The Tank Factory.

DSCF4929.jpg

Share this post


Link to post
Share on other sites

We have arrived at the final assembly stage of the gearbox. Main selector housing fitted and outer engaging housing and shaft, cleaned up and fitted with new seal. The Bevel box unit has been bolted on and the crown wheel and pinion have been set up and shimmed for the required back lash and clearances. The top cover is then secured by the 4 main bolts either side of the 2 bearings and also a series of smaller bolts around the rim. Cheers from The Tank Factory

DSCF4919.jpg

DSCF4920.jpg

DSCF4921.jpg

DSCF4916.jpg

DSCF4917.jpg

DSCF4918.jpg

DSCF4923.jpg

Share this post


Link to post
Share on other sites

This coming week, we commence work on the assembly of the final drives. A couple of pictures of the planetary gears. Cheers from the Tank Factory.

DSCF4930.jpg

DSCF4931.jpg

Share this post


Link to post
Share on other sites

Amazing work Andrew, how many in the team working on it? As an aside, I have just sold a Scorpion to your mate Phil and hope to come out and see you in a couple of years.

All the best

David

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...