TK Bedford, needs a hole in the head

The bigger Stromberg carb off the 250 Falcon or 281 Inter should work fine, doubt these old girls rev as high as the Falcon.
Other than the 350 Holley, the 2 stage Webbers (I think also off the Falcon) would be an option.
Cheers Steve

Could you undo the tray and drag it back a foot or so to get access. ie no lifting gear required.

Well I've put a 160deg thermostat into it, overhauled my own water pump, built a custom 85a alternator, run a battery sense circuit for that, added a circuit breaker, 75a Bosch relay, thermo switch, ignition feed, fuse... and I didn't drill any holes at all.

Filled up the cooling system with cleaner and flushed the buggery out of it, tightened 20 hose clamps, dosed it with coolant and run it all again... seems to work well.

In the current mild weather the electric fans only run for around 6 seconds every half a minute, the control loop is quite short, with the fan sensor being threaded into the bottom hose just outside the water pump, it takes no time to knock the temperature out of it.

I guess the proof is in the pudding when the weather gets hot again, but for now I think we're winning.

Next mission is to get a 30ohm resistor from the electronics shop. Seems you can't buy a temp sender to suit this thing but I have established the gauge readings are about 75ohm hot - 105ohm mid - 330ohm cold. Scouring the VDO catalogue and matching up some numbers I did find a sender with an approximate spread in the right direction, 40-75-280 for memory, so if I can add some resistance to that circuit it should be really quite good. I'm glad VDO still offer proper specifications on parts even if the range isn't massive.

Thanks for your help blokes.

Aaaaaaannd I'm back to fixing the Bedford I think.

The last overhaul had worked a treat for 12 months(?) Electric fans meant it cooled like never before at low speed, alternator had heaps of grunt to keep the battery charged despite doing lots of stops and starts in the dark at seeding time. All good until the radiator sprung a leak at the top tank. The last repairer to look at it was dubious about the durability, so we weren't surprised, it just got topped up when used.

Sadly the chief farmer is very frugal with his words and so he's decided to tear it apart in preparation for seeding... right before we need it running of course. So without consulting me, has taken the whole cooling system apart because "it made a squeal when you built revs up sometimes" Yeah so some alternator belt tension would have fixed that. Shit you could just back the belt off and listen if you reckon the bearings are sus... but no... it's all in pieces.

It was also "overheating" after only five minutes driving... which I suspect means it has a blown head gasket that I can't diagnose because it's already been taken apart.

Are these old buggers prone to compression leaks into the water jacket?

Does anyone think a compression test will show this up before the brand new radiator and whole cooling system goes back in? Could we plumb some compressed air into each cylinder and listen for leaks into the water jacket?

cheers

Anthony

Yes a compression test will tell you a lot. Don't forget to have throttle wide open to allow full flow of air in.

If’ it’s a head gasket it would spew all the water out and with pockets of air in the system, I know the alternator being loose won’t help either .

So the compression test didn't say much. Between 110 - 125psi and they all lifted 10-15psi with some oil sqiurted in the holes.

We've hung it all back together and given it a run but I'm not convinced.

The temp gauge always used to read very low too b#gger all, however the AU falcon electric fans were -very- good and would happily cycle in and out.

I've fitted a new temp sender & balasted it with appropriate resistors to get it into range. It's very responsive.

Now she starts and runs steadily & quietly as ever, but, seems to build pressure in the cooling system faster than in builds temperature. ie it squirted hot coolant and steam/vapour out the header tank before the fans started cycling, and when they did come on they took longer to cycle off despite the cool ambient temperature.

We'll try again tomorrow but failing that, where do I go for a 300ci petrol Bedford VRS gasket set these days?

Cheers

You got a blockage some where in the system. Time to start taking bits off and have the radiator properly flushed out, remove thermostat open the heater up if fitted and jamb the hose up it and back flush. It is alos good to blast a low pressure shot of air into it as well as it causes a shock wave and will loosen stuff.

Auto Surplus for gaskets.

We fixed it... for now at least.




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They're brilliant.