3B loosing power under load.. sometimes..

[brisveganbj42]

well.. this has happened once or twice before.. but not really in the middle of driving.. when you drive along you can rev the engine but its almost like the clutch has gone (there is no grip on the input shaft or something). i can still kind of drive but i have to change down heaps if i get to a hill.. and would have to go up in 2nd at like 2800rpm..

If i stop the car, turn it off and start again.. the problem usually goes away...

ive had this before but its usually been noticable after i start driving.. the first of the 2 times it happened tonight it just seemed to happen.. as if it had just got worst.. i pulled off to the side of the road.. shutdown, started up and she was all good.. the 2nd time i had just gone over a real rough patch and got mega steering wobbles (different story) and then the loss of power..

its like chalk and cheese between difference in performance. when its good you can give it a bootful and hear the exhaust note fire up.. when its doing this weird thing you can have your foot flatt to the floor and it just putts along and it can't seem to get enough drive or something..

thinking back im pretty sure the revs were accurate when there was no power (as in the guage read 2500rpm but it didnt feel or sound like it)..

the history on this motor is that it was supposedly rebuilt about 80,000kms ago but i dont have receipts or proof of that from the P.O.

any suggestions or places i could start looking would be appreciated.

[Joe Egolf]

My 2cents worth are , Check air supply -filter and system ducts for obstructions and or collapsing . Check fuel filter[s] and sedimenter?? Diaphram ok ?? My best guesses?

[Otterav]

I had the same thing happen to my 2 1/2 tonmilitary truck. The truck wasn't used much and had contaminated fuel from another owner, seems the intank fuel pump pickup would vacuum up all the rust flakes and crud in the tank when the fuel level got lower than 1/4 tank. Turning off the engine while coasting would slosh the fuel aroung enough to wash the crap off of the tank filter and when I restarted the truck it would run fine for awhile, repeat. When I finally removed the tank there was almost one qt. of solid crud in the bottom of the tank. Clean your sedimenter first, you may have to flush the tank also.
eric

[brisveganbj42]

interesting... with increase fuel costs i have been running closer and closer to emptying the tank.. (first time i was able to put 70lts in my 40!) so maybe this is it.. but i filled up yesterday.. but it could just be some residue in the fuel filter, as you suggest..

thanks guys i'll check it out

[joshoisasleep]

Sounds like maybe a sticking valve? I had a samurai once that four guys could hold onto to stop it driving away... got into the engine and had a burnt valve eliminating a cylinder. Maybe whoever rebuilt it did something bad and one of the valves is sticking open or closed? The similarity here is that since they're both 4 cyl engines, missing one cylinder is a big deal...

?

[brisveganbj42]

true.. i hope its not something that bad..

i have noticed a lot of smoke coming out of the blow by today.. i spent all day wheeling and didnt have any issues all day.. fingers crossed its just dirty fuel..

[brisveganbj42]

Got my 40 serviced today and chatted with my mechanic in regards to this issue and he reckons that the clutch is on its way out.. he said something like "it sounds like the diaphram is going" .. no idea there was a diaphram on a clutch... this is why I can turn off the car, and back on to get it working again..

anyway.. he's adjusted the shaft on the slave cylinder and its maxxed out so that suggests that there is no much meat left on the clutch..

anyway.. just thought i would update this thread for anyone else who might have similar issues..

[Turbo45]

the way i see it youve got somthing floating around in your fuel tank and it sucks up to the suction every now and then, this happens fairly regularly to the trucks i work on. Do you have a pyrometer? if you do you would notice cooler then normal temperatures when you have yer boot in it because the fuel cant get to the cylinders to make power and heat

[brisveganbj42]

yes i have a pyro but i dont have it hooked up to a constant -ve grounded 12v source (when i do the guage goes wierd) its currently hooked up to a 12v battery in the glove box.. (manually).. and ive been lazy so it hasnt been on..

i also have other clutch pedal issues (adjust to spec then 1.5wks later it requires multiple pumps to work properly. the slave cylinder shaft is maxed out in adjustment.

its weird.. i had a full tank when i had the issues the time that prompted me to post, and luckily i havent had any issues since.. if it was bad fuel wouldn't the issue have persisted for the live of the tank.

[2 Bees]

It sounds like you have a bad lift pump.

Classic signs of a bad lift pump are:
rough start, stalling, no power, air in fuel lines, next day it runs ok.

It will drive you crazy!

Here in the States we use the universal pump from Bosch 2 447 010 033 (Denso 09219-50).

If you can't find one, use the one that Mercedes uses on there 1980's diesels it's the same one.

$15 USD