R Cubed

On booking entry form it says the booked in vehicles must use the Campbell gate entrance ? where is this on the site off which roads so I know the best way to approach site !!

Welcome to a potential CCKW owner.

The Banjo axled trucks do have a better spares backup as already said, they were used for the base of the DUKW's. It is worth mentioning that the two types of trucks ie a split axle and banjo axle are completely different from the main gearbox backwards including the chassis the only main common parts are the engines and main gearboxes from there on they are specific to the type of axle fitted also if you are up in the north of the country you might want a closed cab as these are much warmer but also not as wide about a foot narrower than an open cab.

A well set up truck with a good engine should give you about 10mpg depending how you drive it.

Tyres are about the only other big expense generally over £150 each.

Good luck

Would be a cool air con unit for all those hot days at military shows ! You could even charge pepole to keep their milk and beer cool ect ect the uses are endless.

Is the bigger one not re-usable or would it not stand filling, could you get a fire extinguisher company to have a look at it.

Great, looks like an onsite wheel wash station too....

Could be oil pressure switch or a take off for an oil pressure guage !!

Hi guys, well here is a little update managed to get round to taking some pics of the inside of the cab with new stepped firewall and toe board / floor.

Dont forget you can use Vaseline ( petroleum jelly ) on all battery cable ends and on the connections on the batteries, I use it on all the joints especially the straps to chassis rails, make sure all paint removed down to bright shiny metal apply good splodge of Vaseline and bolt up tight wipe off excess and paint over.

Has worked for me for years and years on all my vehicles, and a bonus you can undo them if you need to.

Got some engine bay pics.

Note cab firewall and rad are both in their original positions. Below you might be able to see a frame on the rear of the rad this is to carry the electric fan.

The length of the GMC engine bay from firewall to rad is 30 1/2 inches.

You can see there is not much more room to move the engine any more forward. Right at the bottom of the pic below the crank pulley there is the engine and rad mount crossmember which is part of the chassis as a guide for reference.

The thickness of the fan is 4 1/4 inches from rad core to back of fan motor.

Right this is the measurement from the rear of the cummins cylinder head to roughly the front of the crank pulley.

Yep thats it 34 1/2 inches.

and here you can see how much is in the cab, looking down the cab firewall towards the top of the engine, it's about 1 1/2 cylinders which is about 8 inches..

Interesting, thanks.

Watched the film Convoy the other week and in the last bit of the film on the bridge with all the "Army" there is a Tank or anti aircraft gun, where Ernest Borgnine is on top of it with a machine gun.

Does anyone know what it was and used for.

Richard,

 

I'm using 24 volt start and 12 volt electrics.

 

The fuel filter on the front at the top of the engine is something the bus company dose. I'm guessing lack of space in the engine bay? I will be moving it once I get it in the chassis.

 

I can get you some pictures of the Perkins P6 engine in a GMC.

 

Jamie

Jamie

Do you have any idea of what the HP rating is of your 6BT ? will probably be in Kw on the rating plate on the side of the timing gear cover.

Jamie, I run a non-turbo 6B in a heavily laden Bedford MJR and would not hesitate to use the same in a GMC. They are a lively responsive little engine giving out 130hp even without a hair dryer, and unless you plan to tow a gigantic piece of WW2 arsenal around I see no necessity for a turbo. But the more pics of the R36BZF conversion I see the more I like it!

yea, I think the non turbo 6B's were about 130 HP but when DAF started producing the 10 Ton tipper for the ground workers they needed a bit more so stuffed a small turbo on them which generates about 10 psi and boosts the HP to about 150 HP, which is what I have in my GMC, also it does not have any waste gate presumably it cant build any more pressure due to design...

I seem to recall comparing a 6b against a P6 and ruling it out for a GMC, but I might just have to measure up again if you are confident. I'm sometimes not too good with tape measures..... :-)

I will get some pics of the engine in my truck I recon you would have to do what I have done as the engine is as far forward as I could get it and still have about 1 1/2 cylinders in the cab!

I think the P6 required the rad to be moved forward? Which may be the only reason I ruled the 6B out? Perkins supplied a complete kit with all stuff required for the GMC conversion including a special flywheel housing to mate with the box and I believe brackets for the radiator move?

 

Great work on the adapter rings!

 

Tony

Well this is the next stage how to fill in this massive hole and make it look respectable. This is prety much the finished firewall come floor panel, which has a compound curve to cover the bellhousing of the ZF gearbox and then curve down to a flat floor.

I decided to retain all the 24 volt electrics on the engine, starter motor and alternator, so this then involved changing all the bulbs ect to 24 volts, what did I overlook !!! yep as it would be 24 volts there would be two batteries !!! damm where to put another battery... well as this is a SWB truck there is a space in the same place on the left hand side as there is for the original battery bracket which is on the right hand side under the fuel tank. Ah ha easy just make another battery bracket in the same style as the original. Enjoy..

The two lids original and the new one, can you spot which is which !

The two battery brackets original and new one

If you break the circuits down into their loads ie what bulbs are on that circuit add up their wattages which will give you the total load for that circuit then divide that by the voltage, that will give you the current for that circuit.

Then just pick a type of cable which will handle that current.

All you need to know is watts divided by volts gives Amps.

You can work the other way too by timesing volts by amps to give watts.

Richard,

 

Regular topping up is exactly my point. How often do you top your car up? Very rarely I'd imagine? Should be the same for a Cummins system, but only if you have a pressurised system with a header/expansion tank. Having a system with the potential to self-evacuate seems like a recipe for disaster to me...

 

My old WLF was running the original rad and after a long journey there would be a stain of coolant running across the tops of both wings. At that time I hadn't done enough conversions to understand what the problem was.

 

- MG

I dont get the coolant constantly running out no matter how long the run in the truck is it always seems to go down by the same ammount just like the old engine use to I always top it up before every run so I know how much is in there. then before the next run I check it again and its about the same ammount. saves modding the rad and fitting another expansion tank.

I'm going to try the same I have done for my Halftrack with our GMC, using the Cummims engine and the GMC gearbox. It should fit straight in as my granddad put a Perkins P6 in his years ago and the Cummins is shorter than the Perkins engine.

 

Im going to look into the header tank, there is obviously a lot more room under the Halftrack bonnet compared to the GMC.

I dont see how you can get a Cummins 6BT in the engine bay of a GMC without cutting the firewall out, my cummins is only 3 inches back from the original rad just enough to get an electric fan in there and I have about 1 1/2 cylinders inside the cab :cool2: but good luck. Would love to see some pics of the p6 in the GMC !

You can also get alternators with vacuum pumps on the back of them I think it has been metioned before that Ford transits do it this way, depending on what voltage you are using 12v or 24v this might be another option you could consider.

Keep the pics coming.

Why is the fuel filter where it is on top at the front of the engine ? usually down the side by the fuel pump.

Hi all, just to let you all know the new 2015 show details and booking forms are all up on the site go here to book in.

I know the link says 2014 but the pages are all up to date.

Tthe link below gives all the details wether you are an exhibitor, trader, food vendor or re-enactor, at the bottom of the page it also shows the map for the site.

See you all soon.

www.solentoverlord.co.uk/blog/overlord-2014

 

I'm assuming you plan to re-use the existing radiator? If so you will almost certainly need to fit a header tank as these old rads are not designed to take the pressurised cooling system of a modern engine. If you don't fit a header tank it will probably spew the coolant out of the overflow until there's nothing left in the system but steam. Don't ask me how I know... And if you try just fitting a higher pressure cap you'll almost certainly burst the core.

 

- MG

This is an interesting thing as I know you have mentioned this to me in previous conversations, however I do not have a header tank on the GMC and the cap is not sealed tight. I do fill up the rad untill I can see the water over the baffel in the neck of the rad and then during the trip the level falls to a happy level, does not seem to matter how long the trip is. Then when I re top the water it only takes about a litre or so this seems consistant with how the old GMC engine use to opperate with the water level so no problems here at the moment. But the top of the rad is a fair bit higher than the top of the head on the Cummins.

Trevor,

 

The fixture will come in handy again as I have another engine coming soon and a 1941 GMC at home......

You might want to do a little research if you are considering fitting one to a GMC as I think in the 50's or 60's the Dutch tried these to the original clark boxes and constantly blew them up. This is why I went down the route I took with the 6BT and ZF gearbox.

Good luck.

Ok guy's here comes the goury bit if you are squeemish dont go any further, you have been warned.

Extreme firewall cutting... :cry:

Right bit of a recap then, so I have sorted out the mounting of the engine so the next step is to get the cab to go back on the chassis from wence it came.

the next couple of pics you can see how close the engine is to the cab, and it's not even in the right place !

At some point I had to decide how the best way was to achieve this, and yes it meant I needed to cut the firewall out, now this is something I really did not want to do but compared to all other options, such as moving the rad forward and lengthing bonnet and engine side panels ( not an option really ) to moving the rear body back and fuel tank and then moving the cab back and doing the same with the bonnet and engine side panels ( not an option really ) so what else was I to do. I decided that there would have to be only one cut around the depression in the firewall, one cut so there was only one panel to put back if I ever decided to return it to original. As you can see the route I chose meant the cowel vent drain had to be removed and was also crooked.

Once it was removed I could start cutting.

Here is the finished hole, :shocked: its big but only one cut so better than lots of little bits.

Here the cab is almost in the correct place you can't quite see but there are about 1 1/2 cylinders inside the cab :cool2:

As the engine sits so low in the chassis I did not need to use the large curved part of the hole so that was paneled in this left a nice square hole to fill.

Here is an inside view of the cab with the engine and gearbox in the right place, as you can see the ZF gearbox has a large bell housing which is above the floor line of the cab....... Next instalment how to spend days and days bending sheet metal to fit around this strange shape and make it look respectable...

looking forward to it, may bring the QLR this year rather than the Vietnam era stuff. Mix it up a bit

 

Is the 2015 form on the site? I can only find the 2014 form

No 2015 online form at the moment all I can sugest is give the 2014 form a go :blush:

Here is a link to the Solent Overlord web site.

http://www.solentoverlord.co.uk/blog

go to Overlord on the top of the page and then click Exhibitors for the form good luck see you all there.

All plans underway for this years show at the usual place over the May bank holiday as usual.

Dates are Sat May 23rd to Mon May 25th.

See you all soon.

Trying to put all this in to a logical order, so I think the next step would be to go over the engine and gearbox mounts as it's about this stage that I had decided on the final position of the engine and gearbox.

I was fortunate that the kind person who took the engine and box out ( you know who you are :cool2: ) also took the gearbox mounts off the donor chassis, so I had the brackets which bolt to the gearbox bell housing the rubber mounts and the brackets which would have been rivited to the chassis, a stroke of luck was these chassis brackets fitted with out much adjustment :shocked: but the position on the inside of my chassis rails meant the rivets for the front mounts for the cab were in the way so they had to go and I took the decision to make some new cab mount brackets rarther than cut the originals ( good aren't I )

So here are the gearbox chassis mounts there was only a need to split the two parts and move them a tiny bit but too much to not do it but there you are.

The fourth pic is the bracket which bolts to the gearbox and it's rubber mount, one each side of the bell housing.

Cab mount brackets, spot the difference !! yep my one is the bigger and thicker one. The reason for this was that the green bracket is the original one and where they were riveted to the chassis put the rivets in the way of the gearbox chassis mounts. Making the new cab mounting brackets which were longer, meant I could use the same bolts which held the gearbox mounts to the chassis to also hold the cab mounts. Cool.

The next pics are of the original front engine mount and how it comes apart and the parts of it. In the third pic there is from left to right the oil cover for the rubber mount the metal plate is a retaining plate to stop the mount coming apart the third bit is the old rubber mount in it's steel holder and the last bit on the right is the new rubber mount ready to go in place of the old mount.

This is the start of the front engine mounting bracket, nice thick bit of c section channel to fit over the engine mount rubber, and provide a base for the rest of the bracket to fit the engine.

Here you can see the new 12mm thick side plates for the engine which are at the moment just tacked to the cross piece under the front pulley.

Here is the finished front mount with some added cross fillets added.