A was for Austin, but now B is for Bedford

Could a clean 20 litre drum be used as fuel tank, could hook it straight to the lift pump and see the results, if any improvement at all would suggest it's further back up the system towards the tank

And possibly the carby base is warped as everyone just "nips it up a bit tighter" to try and solve a vacuum leak

Paul

Cobbadog,
The fuel leak is beyond me. It does not appear to be leaking outside the system and the only entrance to the bowl is at the top. (from the pump) I have put all new gaskets in carby and pump and replaced the valves in the pump. I have cleaned/replaced the filters and even cleaned out the tank. The connections on the pipe are not leaking. The weather has not been hot enough to blame evaporation.
I cannot think what the problem might be.

Morris.

Initial action: Took the carburettor off, all looks fine, pulling fuel through the jets cleanly when using venturi action by blowing air down the carburettor. Haven't pulled the jets at this point as they are probably working fine as is, but will probably do this anyway while its off. Waste of time, unnecessary?

Sidenote: The Holden and Humber carburettors are much wider than the J Type manifold, but closer to the early manifold that I used when I first had the engine running in the bare chassis (3 or 4 years ago!?). The Holden one might still work with a bit of filing. 

I then reflected on the figures recorded when I was doing my two trial runs with the GPS , , .
 
. . . and considering the low ratio diff in B for, 7.4:1  , this truck would have been good for about 35mph with a following wind (gale force). Interestingly the spare engine that I have brought home recently was regularly driven, fully loaded, to Adelaide (200km approx.) and the owner said the trip used to take him 4-5 hours at a steady 30mph as it couldn’t manage much more than that!

Hmmm? In hindsight am I possibly expecting miracles from mine? It was happy while puddling along at 56 kph which is the equivalent of 34.8mph . . so unfortunately I guess it is just woefully slow.    

It may be worth pulling the jet to check the little holes in the emulsion tube....
I usually find most / all of them blocked.

Jarrod.

Possibly similar motor and transmission in the late 40’s Bedford school buses we rode in about 1960 in country Victoria.
Some drivers wrung their necks in each gear getting them under way, sounded like they were flying. Maybe 40 to 45 mph.
Motors did an amazing job really.

PDU, even my 1972 Acco has a 7.1:1 / 9.01:1 diff (2 speed), and it has carted 3 loads of grain per day during harvest from Lock to Pt Lincoln, pulling an 8 wheel dog trailer...................  Petrol was obviously cheap back then.............!

I tend to think that by the time these trucks become our "toys", just accept them for what they are, what ever they are, and sit back and enjoy the ride.

Brett.

I guess that even towards the end of Bedfords in Australia they were never regarded as fast or powerful
They were regarded as a good old work horse that poked along

Even those Chev C60 and C50's from the late 70's were slow and topped out at 90 k's

So 35 MPH probably isn't to bad with a big streamlined box on the back for B for

Paul

Back in the 70s while operating Earthmoving equipment the break down / fuel truck was a J series Bedford. It had a tall closed in body like what the prisoners were transported around in I think they called them the Black Mariah. 
Anyway the engine was due to be done. Boss man wanted to put something bigger in it to get it moving quicker. Fitter told him that the boss is not going to change anything just replace like for like. Reason he said the original engines just kept going had a good torque range n were reluable. The fitter won.

Now I haven't been doing much with B for since my last post, but I have been checking out the recent spare engine that was "dropped" out of its engine bay with the truck upside down. 

Prior to doing that I removed the fuel pump, carburetor, distributor cap and rotor button (left the dissy in place to keep it where it was running) and shook the engine and gearbox free. Inspection revealed damage to the vacuum advance part on the distributor that appeared to be a simple repair - no doubt during the drop which must have been on that side. Pleasant surprise on pulling the plugs as all were clean, no carbon deposits and despite the outside appearance would be worth trying after a general clean up. Next move was trying the starter motor, which proved to be sluggish . . . but after some routine attention to maintenance issues (off the engine) spun freely again. 

With things looking promising I thought I'd do a compression check and see if there was any action at the points . . . I didn't get that far as turning the engine over with the starter motor revealed a distributor that was gyrating bodily as it turned!?  After setting the engine on TDC, number 1 (incidentally the first of three engines where I have actually found the small ball embedded in the flywheel)  the distributor was removed for further analysis.

Bent shaft and cracked aluminium casing, confirming it must have dropped on that side (hard) after all. 

At this point I turned my attention to cleaning the carburettor jets from this engine, and the spare D Type truck which remains in the carport still waiting for me to hook up a remote fuel supply to it. (Too many side issues and minimal incentive to address the situation?) This is easy enough to do as the fuel bowl detaches without removing the carburettor, giving access to them all. The jets were fine, but both had the small accelerator pump piston solid down the bottom of their bowls; these have been left to soak for a week/month or so before I make another attempt to free them. As a last resort I may need to drill a hole in the bottom of the bowl to allow a punch to pass through the casing, up through the light spring (that currently is unable to lift the piston) and then apply some inertia to the piston . . . hopefully.

Moving along I decided to fire up B for and take it for a second attempt to reach the next nearest town, a tad over 20 km. This time with no expectation to reach any great speed I started it ticking along at 50 - 55 kph while the tyres sorted out the flat spots from sitting. By the time I had left the town limits things had smoothed out and I continued at 55 for about 5 km, after which it was happy to extend itself to 58 kph for the outward journey. Please note I was not attempting to push it any harder as it felt happy enough at this speed, even floating occasionally into the 60 - 62 kph range without undue stress. This higher speed continued, even when climbing a long uphill stretch, after which I took it easy on things and dropped to 57 kph for the remaining 10 km home again. Wife was surprised to see me home again so quickly, ha ha, thought I hadn't even left yet!?

So I thought I should report back that I have succumbed to driving at a much slower pace than I usually drive at, and will endeavour to try longer runs as I come to grips with things. Currently a trip to Port Pirie (about 30 km) is only a remote possibility. Time will tell, just bear with me.

Pictures will be added later, sorry.

Good to hear of more progress and it will only run better the more you drive it. A longer trip to Port Pirie will be good to do just make sure its fuelled up before leaving. Glad you have achieved a more sedate driving pace, as it will also save on fuel burn rate.