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mike that was my cromwell coming back up from the chalke valley weekend. 580 hp scania tractor unit and fancy trailer guy told me the rig was worth 1/4 million. only trouble was it kept breaking down with a computer fault. much better to stick with the old trucks :)

 

 

been flat out tanking for last week or so and haven't had time to post any replies but yes the foden passed it's test and i picked up john's valentine from cannock yesterday (baptism of fire) everything went well and the tank is now at the ywe site.

i'll get some pics up next week

 

rick

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having a few problems

 

after i unhitched the trailer and left for home the foden broke down just down the road from the ywe event, luckily some helpful guys with a diamond t towed me back to the event. i'm just relieved it didn't do it while on my way from brum with a valentine on the back. (no breakdown cover so it would have been costly) !

anyway i think the bosch inline fuel injection pump is knackered but would appreciate any other opinion as to what might be the cause. it was running great but then a couple of days ago the engine started to surge on tickover and felt rough/lumpy when under full power, then whilst driving it just cut out and wouldn't even attempt to fire up. i cracked off 4 of the 6 injectors and got fuel, which made me think the pump wasn't giving enough pressure to open the injectors. before i try to source a new pump does anyone have any other thoughts. by the way the engine is a perkins tx

 

cheers

 

rick

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I'd perhaps check the lift pump first. Some I've come across have a gauze mesh filter across the inlet which gets blocked (older engines). Depending on the type of lift pump, it could be letting air in through the manual lift plunger (I've had this on newer engines).

 

Vince

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cheers vince

the thing is i'm getting fuel at the injectors and it looks great and the engine is not even attempting to fire, i can only think it's pump pressure, which means a new pump or service the old one

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Without knowing what the pump looks like, I've come across a few cases where the rack has become stuck (unlikely as you were driving it), and also had cases where the pump governor has failed due to a lack of lubrication (some CAV pumps required manual lubrication). Failure of the governor can result in the engine not running, or more excitingly leading to (usually catastrophic) pump and engine runaway.

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Another thing that can happen (certainly on Cummins pumps) is that there is a fuel return valve in the top of the pump, and if this jams open all fuel pressure is returned to the tank, thus preventing the engine from running.

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the run up is not the problem, its having b*lls big enough to attempt it, loaded a lot of stuff up steep ramps its not a good experience.

 

I think a HEMTT would be really nice for pulling tanks. They can be bought for around $14K US, many are in post overhaul condition, courtesy of Uncle Sam. I think they have a winch as well. They can probably pull whatever you throw at them. Articulated steering between the 2 sections makes for nice turns. Here is a link to a recent sale:

 

http://www.govplanet.com/for-sale/Trucks-HEMTT-Oshkosh-MK48-HEMTT-8x8-Tractor-Truck-Maryland/640957?h=5000%2Csm%7C1%2Ck%7Coshkosh%2Cpstart%7C60%2Cmf%7C1&rr=0.0137&hitprm=&pnLink=yes

 

 

 

528149_6002_159_0001.jpg

 

528149_6002_162_0001.jpg

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that would get me noticed on the M6 :) but i think i'll stick with the foden

 

vince the fuel return valve sticking open sounds like it might be the culprit. i'll have a look this weekend. cheers

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Rick,

 

I love a Roller!

 

I would put money on it being anything but the actual pump itself especially if you had just been using the vehicle effectively. Even more money on air getting in somewhere.

 

I would change / service all the filters. If you have taken the fuel tank level down low you might have sucked in muck. With this engine I would expect a primary filter / water separator on the chassis and a big filter on the engine.

 

Make sure that air is not getting sucked in at the primary filter.

 

The pump is pressure lubricated from the engine so there is no possibility of governors having run dry etc.

 

Also ensure that the fuel stack pipe in the tank is not holed or damaged.

 

 

The SEME précis for the Perkins 800 LM has the following quotes:

 

"The filter is not fitted with an air venting plug as venting is automatically achieved by an integral stand pipe."

 

"A fuel pressure relief valve is fitted in the low pressure system for the purpose of stabilising the fuel pressure in the FIP pump galleries, the nominal pressure being 19 to 26 PSI.

 

The relief valve is fitted to the body of the FIP at a point diagonally opposite the fuel inlet connection."

 

"The filter header bracket is also equipped with a tapping to enable the fitting of a pressure gauge if required."

 

Having done the filter change and other obvious checks I would check fuel pressure on filter bracket. If that is not up at around 20 PSI that might be the cause. I would not send the pump away if you have not got pressure there and are also confident that there is solid fuel in the pump.

 

The précis give full instructions as to how to remove, refit and time the pump and I can send it to you if nec.

 

I hope this is helpful.

 

John

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thanks john but i had another look at it over the weekend and it definately is the pump, possibly the fuel rack stuck in the closed position or has somehow become disconnected. i got a freind to bring the truck back to my yard and i'll see if i can sort it this afternoon

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