attleej

Dear All, We are leaving this morning with the Contractor and 'little' trailer transporting the Centurion ARV. Unfortunately, despite working my socks off we could not get the 'Big Trailer' loaded with the Conqueror ARV absolutely ready and safe. If anyone wants to touch base my mobile is 07528 263926. John

I expect that I have got an EMER for a Mk III but it is the same system as for a Scammell Contractor. I am a bit busy getting ready for Dorset at the mo but I am sure that I will have some tech info avail IDC. Someone else may also be able to help. John

YES. In my experience it is absolutely essential to have the literature for a vehicle if it is available. You need the user hand book (UHB), the Servicing schedule, the EMER or AESP covering: Technical Description, Unit Repairs and Field Repairs. You are unlikely to be able to find literature covering Base Repair and finally the parts list. You might be able to get a micro-fische of some of this info. Any effort that you expend in acquiring the literature will be rewarded many times over! John

Dear All, Most engines Army engines are rebuilt by static base workshops or civilian original equipment manufacturers. Power packs for Chieftain, Challenger, Warrior, 432 & Bulldog are regenerated by the field workshop. The actual engine or gear-box is replaced and sent back to base. The capacity to regenerate the power packs is a limiting factor on how far you can move an armoured formation on tracks before running out of packs. On exercise or operations time is of the essence. It is much easier just to change the engine than to mess around rebuilding the engine in the field. You also need to remember that the field workshop units have to be mobile within the Area of Operations (AO). The last thing they want is dozens of vehicles in bits all needing one or two elusive parts. Each one would have to be moved to the next location (with the risk of losing components) by the recovery section which has a finite capacity. Richard would know more about how the Base workshops operate but I believe that different ones did different engines. This would mean that they had all the Special Tools and Test Equipment for the engine as well as their stores having all the parts that they might need for that engine. For instance, if something had to be shimmed the relevant base workshop's stores would have all the range of shims in stock. The same considerations apply to gear-boxes and axles and final drives. Collectively, they are known as Engine & Main Assemblies. The bottom line is that it would be very unusual to find an AFV with its original engine unless it was never issued to a unit. John

Mark, If it is only 7 mm I would have thought a suitably powerful mig welder (ie not a mini mig) would be fine. If poss try a test weld of the type that you want to do (ie a butt weld) on a scrap bit and then test it for strength. Grind most of the rust off from the weld area. You need to be careful about distortion but I think that it would be less of a problem than sheet metal on a car. John

Jules, Are you sure that they are U/S? First of all if they are tapered roller bearings there should be some shake. Check the EMER. They might just need adjusting and actually be OK. John

I had the same thing on a B81 in a Leyland Martian. If I worked it too hard it would run rough. It was the points pivot seizing. It was fair enough because I had a blowing exhaust manifold gasket allowing flames to heat up the distributor! It got so hot the condenser came unsoldered. I got around that by using a Landrover one from my FAMTO box and mounting it on the air cleaner connected with a long bit of wire. I think partially seized pivot is a strong possibility. John

Or "simply bearings". Find by google. I have found them to be very good. The local dealers don't have the range because they can't stock everything. John

In the circumstances that you describe, if you are not getting smoke out of the exhaust it must be a fuel problem. Although I have found an exception. The REME Museum's M578 would not start despite plenty of smoke. However, the smoke was coming from the cold start flame thrower device and not the injectors which were seized. Advice already given is, as ever, is good. Check that the stop control lever on the pump is in correct position. John

Dear All, Has anyone got a cross reference for a "Purolator" oil filter assy A.6184. The element is A6428. Any cross ref to a current manf would be extremely helpful! John

Andy, I could make a special tool with my lathe and milling machine. I could make it a large hex drive, say 1". If nec I could make it out of EN16T. All I would need would be dimensions of screwdriver slot. It would not take me long. John

I think that it is the old fashioned military socket that was before the NATO socket. I used to see plenty of them around but Have not seen one for a while. John

Dear All, The rear axles are back on as are the rear springs although they are not notted down yet. Shortly going to do the brake camshafts. They have double needle roller bearings on each end of the camshaft which are dried up. I have got new oil seals to fit. All the brake linkage has been re-plated so it will be quite nice putting that all together. I am very slightly struggling with a large "O" ring at just over 7" dia and 7mm cross section. This is part of the hub oil / grease seal arrangement. The good news is that there are less and less parts awaiting fitting. I bought a sandblasting cabinet from Machine Mart. Unfortunately the see-through top becomes opaque too easily. I therefore am using the helmet from my full sized shot blasting equipment with the cabinet with the door open! This works really well although quite a lot of copper slag ends up on the floor. However, it is expendable! The glass beads worked well on ally brake valve castings. This weekend we are taking the Contractor out with the 'little trailer' to move John Davies's Cent MBT to Milestones Museum at Basingstoke and then on to Loseley Park near Guildford for Sunday. All the for A/F weekend. It will be a little while before I get back onto the Antar. I will try to post some pics soon. John

It is actually info for a project that the Tiffy course at SEME are doing. Currently you cannot drain the coolant from Bulldog without lifting the pack. All the old tech info & ISPLs have been binned so that they cannot determine the NSN of the tap. Hence they came to me and US. John

Dear All, I think that the old harness assemblies were soldered. Perhaps the FV600 ones in Andy's photo were soldered. However, I sawed through and cross sectioned a more modern harness that was off a Chieftain. The assembly is pressed together and not crimped or swaged! The parts are re-useable and are all in brass. I turned up a drift that separates the assy by pushing the centre out. This did mean that I had to cut through the harness about an inch from the start of the fitting. I then reassembled the harness, to the desired length, by pressing the parts together. The difficulty was trimming the braid to the right length. In the end I just cleaned it up with a hacksaw blade. Since the fittings are in brass there is not a rust problem. I intend to produce some drawings to show how they come apart and the dimensions of the tools. I hope that this is helpful. John

Andy, That is precisely the information that I am after! For a bonus 10 points the VOSA / Vocab section? This has got to be the best forum of all. One of us knows the answer to everything. John

Dear All, Can anyone tell me what the NSN for the coolant drain valve on the FV430 range power pack is? I have a suitable valve but I need the NSN for the correct one. John

The same with the Cent AVRE and ARV! John

My experience of a B81 in a Leyland Martian was that it was easy to start on the handle. Just as well because the starter would regularly cut out due to the over-heat cut out device in it. John

We should not forget that it was not that long ago that the Army was using the tanker version to carry 22,000 litres of fuel. You need to carry out the checks suggested. I could give it a try if you like. John

Dear All, I have done this, ie make a 220 a turbo. Members are correct in suggesting that you check that nothing is not holding it back. On the other hand you must expect to have to change down on the hills with only a 220. I took advice from Rolls at Shrewsbury. They said it was all right to fit the turbo and FIP from a 265 and fit it to a 220. The one important point is that the injection timing needs to be retarded a bit from the correct figure for a 265. This is because the 220 has a higher compression ratio than the 265 or any of the other turbo Rollers. If the timing is not backed off the combustion chamber pressures will be too high. If you use a pump from a 265L (and others) it will have boost control. This means the pump will not deliver maximum fuel until the manifold pressure has been increased by the turbo. This type of pump can be identified by a small diameter pipe going between the pump and the inlet manifold. (It is no good just removing the pipe!!) The 305 fitted to the Scammell Crusader does not have this refinement. That is why they can often belch at each 'up' gear change. The boost control radically effects the torque curve. On a 305 it rises very fast from low revs whereas with boost control the curve is much flatter. Unfortunately this means that when you change up the engine might not be able to 'pull the next gear'. The Foden recovery vehicle has boost control fitted. I had a turbo 220 fitted to the Antar for some time until we fitted a 265 with new pistons and liners. Andy Trimmer will tell you that it starts if you put batteries anywhere near it! It is an absolute blinder of an engine. It will certainly stay in the Antar as it is rebuilt. Finally, at Rolls, the Chief Applications engineer said something off the record,very interesting about fuelling. He said that you can "open up a MkIII Eagle until it smokes as much as you can tolereate". I have kept the Antar down to what I think is about 305. Mainly for reasons of fuel economy. I have Rolls literature on these engines. John

Since it is Air Ministry surely it must be for an aircraft and the connectors are consistent with that. I would have expected it to be 24 volts in order to save on the weight of the wiring so I think that it must be quite early. John

Dear All, I don't think that the RTR definition of a "tank" is correct or authoritive. The nomenclature for the Conqueror ARV is Tank, ARV, Conqueror Mk II. I am not convinced that it would be effective against another AFV since it is only armed with light machine gun (Browning or Bren, I don't know which for certain). A chief's nomenclature is "Tank, Combat, 120mm Gun,Chieftain, Mk 1". This rather implies that there are other variants which are not combat or gun tanks. ARK, AVRE, AVLAB and BARV come to mind. I am quite clear that the Conqueror ARV is a tank even if it does not have a sticky out thing! John

In a preserved vehicle, even compressions are nearly as important as the actual figures. If they are not more or less the same you have a problem. John

It looks very similar to the one on a Roller. It may be that the pistons etc are the same. John