Raising the roof.
(making a tilt cab of a Karrier Bantam)
Whilst the cabin was off the chassis being sandblasted, had a bit of a look at what a mate suggested, that was to convert a fixed mounted cab into a partial tilt cab.
Because we were only dealing with the bare cabin shell, was relatively easy to access all areas. Doors had been removed, along with dash, the centre overhead console, in fact as written, a bare shell.
When doing the initial stages of the full rebuild, the sixty odd year old electricals were in a very poor state, besides being a positive-earth system running a generator, wanted to update all the wiring to negative earth to suit an alternator.
Had left the wiring loose enough to be put inside two large concertina cables, running up either side of the steering column.
First thing that had to go was the way the original radiator had been bolted (along with the shroud) to the inside of the engine tunnel. Simple enough as the radiator had already had provision to bolt a plate either side of the radiator frame and run a pair of adjustable rods back to a point on the chassis, same idea as most cab over applications. With the added flexibility of the new wiring, the only restriction on letting the cabin swivel would be the steering column, (shaft went straight into steering box at floor level, with a simple U –bolt clamp like an exhaust clamp secured at the lower dash level.)
Just eyeballing the column and the temporary seat installed to move the drivable chassis, it was probably going to be limited to a 45-50 degree tilt at best. Certainly making the engine more accessible (the original way of engine removal was to take the passenger door off altogether and with an engine crane, manhandle the complete engine transmission unit out through the said doorway).
As all the floorplates had already been removed, most were rotten with rust, the originals had been kept to make templates with at a later date.
With the bare cabin sitting over the original mounting position, a very simple swivel arm was manufactured for each front mount, one side a simple mirror of the other. As the original cab rubbers were shot and replacements unobtainable, new mounts could be turned down out of stock neoprene solid bar on a hobby lathe. The mounting holes for the front mounts were between 15/16 ths and 7/8ths of an inch diameter, both a relatively easy size to get hold of. 3” long 7/8 hi-tense bolts could be used inserted from the bottom up, a neoprene washer approx 3/8” thick either end of the bolts along with flat steel washers and then nyloc nuts would hold the bolts in place.
On the underside where the head of the bolt protrudes, a flat piece of steel could be fabricated with a hole enlarged and then welded together. Then this in turn was welded to a several pieces of 5/8” stock bar which in turn was inserted into several pieces of tube bored out to suit the 5/8” stock. The tube was welded in turn to a short length of enequal sided 5mm thick angle iron. Grease nipple holes tapped into the tube for lubrication. This piece was then secured to the front cross member by drilling out the original chassis rivets and re-secured with hi-tensile bolts. The original brackets which supported the radiator at the bottom were removed with an angle grinder and because an engine driven fan would be replaced with an electric “puller” fan, the radiator could then be moved back closer to the engine, the original two “pins” locating the radiator at the bottom were simply left in place and the radiator repositioned between the two new cabin mounts. The original filler neck for the radiator used to come out just below the windscreen with the aid of a 6 inch long rubber hose. This hole will be “plugged” and given a smooth finish externally. Because the inlets/outlets of the original radiator had to be repositioned, it was easier to have a short “neck” with a low pressure cap made onto the top tank. Checking of fluid level could simply be achieved by taking the top removable engine hatch off from inside.
With no weight in the bare cab, and the whole front cabin now sitting only around an inch and a quarter (30mm) higher than original, was time to look at the rear cabin mounts. The two long “gussetts” which run longitudinally, as well as the one that sits transversally in front of the modified front member, will have to be “beefed” up with probably 4mm “U” shaped and rolled braces mig welded in place.
Should be pointed out that other than a small mounting plate for the PTO control and a removable plate above the brake master cylinder (for checking and topping up), most of the floor plates can be reinstalled with newer slightly heavier material, rebolted in original position and holes.
The two gearsticks where they come up through the floor, can have simple rubber boots fitted and circles (or squares) cut out of the matching plate positions, once it is determined just where the sticks will be positioned.
There will be very limited space between the back of the cabin and the tray. First you have the reconditioned PTO/pump and hoist cylinder to be fitted, then some sort of locking device to secure the cabin in the down position,
The rear cabin mounts are a “cup” shaped affair which originally had a cone shaped two part donut and sleeve, again, worn out and unobtainable, in fact, an "S"line Inter bonnet retainers would go very close.
Again, these could be fabricated out of neoprene with a long bolt recessed into the upper part of the cone and secured from underneath with a neoprene washer, steel washer and nyloc nut.
These two “cones” would be used primarily to locate the cabin in the correct location in relation to the chassis, another securing or lockdown device would have to be installed.
The original hand brake lever cannot be used where it was and another location or type of handbrake has to be adapted.
To gain more tilt on the cabin, for access to engine etc, the steering column would have to be adapted somehow. Whether that would mean using a small Japper type power steering or a sliding splined column would have to be determined. Ideally, the steering wheel position and mounting under the dash would tilt with the rest of the cabin forward. Some sort of restraint be it a safety bar or cable would have to restrict the cabin tilting too far forward.
The weight of the cabin, once doors, seats and other cabin fixtures HAS to be taken into consideration.
The area at the rear centre of the cabin could also be easily “beefed up” and would be an ideal location to install the lockdown device.
The top mounted alternator and bracket has to be relocated back in its original position on the 2.5L Range Rover engine.
There is also provision for a power steering pump on the engine. Would be nice to have assisted steering, either hydraulic or even electric assistance, but at this stage that’s a fair way off.
Things have come to a screaming halt as the shed it is in, is STILL awaiting delivery of the cladding. Chuck in the rain we have had over the past month and the drainage involved, slowed things down to a standstill.
Had a look at my Bro-in-laws “D” series Ford in regard to the chassis mounted Clayton-Dewander remote brake booster set up, reasonably simple, but probably a bit too big for the Karrier.
With an engine change, probably have to go for an engineers inspection anyway. But have given a bit of thought to the tilt cab conversion, it IS feasible!
At this stage, even if I go no further with it (the tilt cab), the brackets and hinges I have already designed and made can still be bolted down rigidly. At the worst it will lift the cabin up a max of 25-30mm, and no-one would ever know! Simply replaced old rubber mounted isolators which you simply cannot get, with neoprene type mounts.
If it won’t work, not a disaster by any means, spent a hundred bucks or so having heavy duty hinges and mounts fabricated. Go back to original configuration.
But whilst I have the cab completely off the chassis (going to make one good one out of two, testing my mig welding ability) now's the time to do it.
Radiator(s) are out waiting to be sent away for cleaning/changing input neck, should get one good one out of the two.
Still a long way to go, brakes have still to be sorted, original 1.5” single circuit master cylinder been replaced with C30 Chevvy 1.5” dual circuit system, wiring just about completed, but cant finish until the cab goes back on the chassis. PTO, pump, hydraulic ram, control valve (for tipper tray) in shed been checked out all OK. Already ditched the original 13” wheels for Karrier16” wheels.
BTW, have brand new 7.50 X 16” tyres, tubes, rust bands BUT what is the MINIMUM width rim that will accept that size tyre? At the moment, some of the tyres are fitted to two-piece 6.50 and 7.00 RIMS, look OK sitting on the rims, but the other Karrier 16” rims were shod with 7.00X16 on 5.00 rims, reckon that may be getting a little narrow.
That’s about as far as I can go at the moment, other than repositiong a few brackets, alternator, jockey pulley etc until I can sit the shed on as a trial fit.
Dave_64
