TK Questions
 

I thought I'd start a new TK thread because Mystery Part was large and off-topic!

Here's one:

Why did they use a mixture of bolts and rivets on the chassis? The rear engine/gearbox mountings for example are riveted AND bolted to the chassis. Why would you use both I wonder?

Without refreshing my memory, ISTR that the engine rear mounting / gearbox crossmember has a removable section to facilitate removal of the power unit - and in particular the gearbox.
The support brackets for this crossmember are rivetted to the sidemembers IIRC.

The support brackets are in two parts (per side) and these are riveted together. The assembly is then riveted AND bolted to the chassis. If you remove the bolts (2) it does nothing because the bracket is riveted (4) to the chassis rail. It's the same both sides so not a repair I don't think.

The stubby brackets are intended to remain fastened to the sidemembers, whilst the crossmember should be unbolted if necessary and removed.

It's the stub brackets I am talking about, probably a poor photo because the cross-member and gearbox are all out now. The stub brackets are bolted and riveted to the side rails.

Interestingly the same question came up on another forum I visit with a chap doing up a much newer truck

http://www.mig-welding.co.uk/forum/t...-engine.49260/

He has completely dismantled the chassis and commented that the cross members were attached to the rails with a mixture of bolts and rivets. The theory is that the bolts are used to align everything prior to riveting

That guy is 'ambitious' to say the least.

I'd love to know if he actually gets it running legally.

It's amazing what these guys get up to! Makes my efforts look very 'small fry'.

The folk on that welding forum (particularly under the Projects section) and others on the Hot Rod forums that I follow do things with metal that I did not even think possible and often with simple hand tools!

Would it be a good idea to use something like this as a pre-filter before the lift pump to remove water and any large debris or is there not much advantage in that?

If so, would it be difficult to bleed if it is on the suction side of the lift pump?

BTW Happy New Year, hope you had a good one

Naked TK Chassis!
 

All blasted and painted in a beautiful pink primer

Looking good.

Chassis in a nice blue gloss now

Why blue?

Black would be standard - I don't think I ever saw a blue one.

I can't remember whether military vehicles were other than black (chassis).

Looks good though - but unusual IMO.

It's a good question and I did think long and hard about it, why blue and not black. Here is my reasoning -

1. Blue is nicer to work on than black, not so dark underneath
2. It's the same colour as the cab so less wastage of paint
3. When the body goes on the chassis will be pretty much completely hidden - current plan is a camper body with side lockers etc.

If the chassis was going to be visible I would have gone for black

It's your wagon, it's your choice! :):)

Do you by any chance have the torque settings for installing the front and rear spring shackle bolts? I have been collecting the training manuals but I don't have that one yet!

Rear ones looked as if they had been loctited.

MK/MJ (20 inch wheels):-
Spring U-bolt nuts - front 95 lb.ft - rear 140 lb.ft
Hanger and shackle bolts and nuts - front 125 lb.ft - rear 190 lb.ft


I do not know the respective sizes of the bolts, and, as stated, these figures are for the military 4x4 vehicle.

Does any one know the right way to remove the two springs that retract the brake shoes? I've done it various times (on cars) over the years but never what you might call elegantly and usually involving bad language and minor injury :-)

There are proper tools that you can buy to do the job. They are basically a big pair of tongs with hooks that locate in the springs and as you close them they release the tension on the springs allowing you to release them. They can be a bit hit and miss however and as it's not something that you will be doing on a daily basis it might not be worth the expense of buying one. I have seen people make up their own versions using a thin steel rod bent over to form a hook at one end with the other end bent to form a loop. Once the hook is located on the spring, a bar is put through the loop end and used as a lever to pull the spring off.
Hope this makes sense as it's hard to describe something without the aid of a picture.

There was a tool that was like a lever with a pivotting link attached.

The lever end was 'anchored' against the backplate and the (wire) link hooked around the end of the spring then, using the leverage advantage of the tool the end of the spring was pulled away from the shoe.

The manoeuvre was reversed to fit the springs.

It would be easy to lash-up a tool like this - you just need a sturdy piece of metal for the lever and a suitable length of wire with an eye one end and a hook at the other.
This wire needs to be hardened after shaping.

The eye end of the wire attaches to the lever via a 'stud' or bolt (such that it is free to pivot).

The distance from the end of the lever depends on the size of the brake and the strength of the springs.

I'm sorry that I cannot find a photograph.

This is the nearest that I can find:- http://www.fiskars.eu/var/fiskars_em...rning-Hook.jpg

Thanks so much for all the help guys! These forums are such great resources for amateurs like me.



Following various advice I got the springs off pretty easily with a large pair of water-pump pliers and a lever. I may well make up something special as suggested above to put them back on again.

The parts seem largely OK except the cylinder which has scores and was leaking into its boot: new parts on order. The back plate, hub, drum and wheel will be blasted and painted.

I stripped down the foot-brake air valve.

There are air two chambers one of which was quite clean and the other was full of white powder. The cylinder bore seemed good but then I noticed that it was cracked so I ordered a new part.

Came across one of those strange bits of pricing. A rebuild kit which by me reckoning contains a handful of o-rings and a filter is UKP128. The bit you see in the first picture is called a foot-brake 'portion' and is UKP 230 complete with all the internal bits and the entire valve which includes the angle bracket that you see in the last picture is UKP403


It seems that the portion is by far the best buy so I ordered one of those.

Dismantled the rear cross-member and gearbox mount. What an elaborate set-up! I wonder why.

• 1 cross-member
• 2 large castings
• 4 rubber bushes
• 4 large bolts
• 4 special bolts with coachbolt style head and reduced threaded section
• 4 dropper plates

Putting the condensate tank back on. Does anyone know what the threads for the fittings in the air tanks will be?. I had assumed NP because of the GM connection but the guy from the local truck parts store reckoned BSP.

Attachment 351

Sorry, memory doesn't last that long.

I would favour BSP.

Turns out they are NP.

I bought a set of three plug taps on fleabay for $33 delivered. I probably will never use them to cut new threads but for cleaning out old ones they work very well.

Shiny new front brakes
 

A few shots of the front brakes going back together

Does anyone know what the two air brake circuits are called? One is the service brake and the other?

One is fed from the smaller of the two tanks and goes via the foot valve to the 'end' of the servo, nowhere else.

The other is fed from the larger of the two tanks and goes via the foot valve to the 'middle' of the servo. This one ALSO feeds the handbrake lever and the anti-compounding circuit for the handbrake.

What would they each be called? Just interested.

It depends on the age of the vehicle.

It might be Service and Secondary but Primary and Secondary circuits are normal descriptions, however, it isn't unusual to have two primaries as well as a secondary.

Typical Air-over-hydraulic System.

Modern vehicles have dual-circuit systems which might split the hydraulics as well as the air, thus reducing the possibility of total failure, so with one circuit failure you would still have adequate (if reduced) braking available.

The secondary circuit must achieve certain parameters - and might be applied through the 'parking' brake.

Many people overlook the handbrake as being available when the wheel brakes have failed, but it will usually be certified as a secondary brake application system.

The truck is 1980 and has dual air circuits driving a servo to dual hydraulic circuits. The handbrake is a spring brake on the rear axle that operates the wheel hydraulic cylinders mechanically.

The difference between the two air circuits is that when one fails the handbrake will lose pressure and the brakes will apply whereas when the other fails nothing much will happen apart from the buzzer in the cab. I can't quite get my head around the logic of having the handbrake apply when one system fails but not the other.

The handbrake will be part of the secondary system.

Brake systems should be designed such that any single failure leaves the vehicle with the ability to 'stop' - albeit with a reduced performance level.

If you lost the 'primary' circuit you would still have reduced footbrake performance (via the servo) and also secondary braking via the handbrake.

Losing the secondary air removes the ability to replenish the spring brake (though you could arrange a double check valve from the primary service reservoir).

Later models would have multiple circuit protection valves guaranteeing air supply when other circuits had 'failed'.

That makes a lot of sense; I understand the different failure modes now.

BTW - Happy New Year!

Does anyone know the procedure for tightening this nut after replacing the propshaft centre bush. It tightens up exactly between two slots and if you back it off it is not much more than finger tight. Mind you, it was not very tight when I took it apart. Just wondered.

For the sake of completeness - it's 240 lb/ft and then more to align the split pin; you don't loosen it.

Does anyone out in TK land know where the clutch arm return spring is meant to attach? At the rear it clips onto the clutch arm but there is nothing obvious forward of there for it to go onto. Any ideas?

Unfortunately my manual doesn't detail where the spring is anchored, and the illustration that shows it in situ is schematic and not 'realistic'. Is there anywhere within reach of the spring that would be 'obvious'? It could be a bolt head (might there be a bracket under the head of a bolt?).

My manual just shows it 'flying' but it does show a little angle bracket. I guess it must be onto one of the starter mounting bolts. I was looking for an attachment point straight ahead but I notice now that the drawing shows it angled.

Hello all I have just joined so not sure if this is the right place to ask but.... I have a 1970 km tractor unit with a 466.... I have destroyed the engine.... please dont ask how.... I have a bedford 500 turbo to replace it. The question is, Is it possible / advisable to remove the turbo and replace it with the exhaust manifold from the 466 engine ? Will I also need to swap the fuel pump and compressor...? How will it effect the engine ? Am I wasting my time or should I just find a non turbo unit >? Thanks

Why don't you keep the turbo?

I am limited to time It is a working lorry and need it back on the road asap..Keeping the turbo means fabricating a new exhaust etc