3b 60 - only 18mpg? - Warning - math content... (1 Viewer)

[brownbear]

If I'm not on the floor I would never get out of first gear. I'm wondering if there is something wrong with my accelerator linkage...??

A BJ60 is not supposed to be like that amigo.

My Bj60 only needs to be breathed on for acceleration. It's only the 60 kph to 100 that is sluggish. The bottom end jumps right up and thru the gears with next to nothing for gas pedal pressure.

If I was you here is where I would look first.

- take the tube off the intake at the butterfly. have someone start to push the throttle(engine off) watch the butterfly. See that it starts to move right away, also see that it goes fully to open when your foot is all the way down.
-next have a really good look at the tubes that go down to the injection pump governor see that there is no cracks or holes. visually. They control the pump thru differential pressure.
-next if you have no clue as to when the diaphragm has been replaced in it's 23 yrs of service, just replace it. It's the main control mechanism from the butterfly.

If your injectors have not been serviced(removed and replaced with serviced ones) then plan on doing so.,

Also your injection pump may not be timed ideally. Which you can do, but I would be inclined to let a diesel injection shop do, with the nozzles too.

If you have to floor it to move the truck there is a problem.

 

[earabadj]

Beside the mechanical issues, injector pump/nozzles fuel filter air filter winter diesel etc ...
I noticed that my habit of driving changes in the Winter; I don't turn the truck off as often as in the warmer weather, and of course while not counting Kms the truck is still running/idling. I would think that counting hours of operation would be more accurate then one can factor in highway v/s "in town" driving.
Does this make sense (or just "me" self ?).

 

[SURVEYOR CRUISER]

Not bad fuel economy for winter. my 85 bj 70 with a axt turbo has been getting 19.5-20 mpg.
Summer it jumps to 22-25 mpg. I also live up some big ass hills with lots of curves. If you are concerned about injectors.
Go buy some lubrimoly diesel purge... pull the fuel feed hose off the injector pump and run it out of the can as instructed. This always helps things run smoother. I do it twice a year in addition to always running a cetane booster and injector clean per everey tank.
This method works... I have almost 400,000k and no injector problems

 

[MrMoMo]

Thanks Brownbear, I'll take a look at that. Perhaps I was exaggerating a bit, but I always found (from the first day I drove it) It really needs most of the pedal to get going. - acceleration through 1st, 2nd, 3rd is OK, but definately needs lots of the skinny.

Swapping on my 33's today I did notice that the drivers side front brake was dragging. I think I freed it up a bit but perhaps a caliper re-build is in my future.

Scarily I also found that the lower pad retaining pin on the passenger side was almost all the way out!! (the retaining wire broke) I think the only thing keeping it in was the rim! - it had not worn the head off so it must have just started coming out. (whew!)

 

[bj42turbo]

I just come back from a run up our state (for aussies up the hume and back), sitting between 100 - 120km and got around 16.5L per 100km, note this is aproximate as I run 34 inch tyres and speedo is out around 9km at a speed of 100km according to a overhead speed check we have just out of town.

BJ

 

[freebie]

FYI
Mrmomo, don't forget 4.54 L /Imp gal?? unless you are trying to convert to the US equivlent mileage???
that brings it up a little more.

 

[MrMoMo]

Who uses imperial gallons?!?!?!

3.78L per G in my mind...

 

[brownbear]

Who uses imperial gallons?!?!?!

3.78L per G in my mind...

Funny...but most Canadians use imperial gallons when they think of MPG. Why? Cause they are old and fuel was sold in gallons(imp) in their day.


US gallons... Nobody here uses that.

 

[lowenbrau]

Funny...but most Canadians use imperial gallons when they think of MPG. Why? Cause they are old and fuel was sold in gallons(imp) in their day.


US gallons... Nobody here uses that.

I dunno, count me as one of the others. If I'm talking gallons it's because I'm talking to someone who doesn't relate well to Litres. By definition that means an American.

I figure there are only two meaningful units of measure for things like fuel. Litre and gal/US

Imp gallons have gone the way of the Cubit, Stone, Rod, Circular Mils and Furlong as a way of measurement.

 

[Dougal]

Who uses imperial gallons?!?!?!

3.78L per G in my mind...

Considering there's only one country in the world who uses 3.78L gallons, maybe the question should be rephrased?

 

[freebie]

Hey
I was not wishing to start an International debate on historic systems of measurement!!
I was just pointing out that there is a difference and I have seen this mathematical mistake made before, having said that it is very common to compare vehicle mileage with the US system? and with great displeasure (brownbear) I now see the advantage of the metric system!!!
BTW (old) I resemble that remark!!

 

[brownbear]

I dunno, count me as one of the others. If I'm talking gallons it's because I'm talking to someone who doesn't relate well to Litres. By definition that means an American.

I figure there are only two meaningful units of measure for things like fuel. Litre and gal/US

Imp gallons have gone the way of the Cubit, Stone, Rod, Circular Mils and Furlong as a way of measurement.

Oh I admit if I'm on here I too will quote in US gallons just because of the audience.

But in my mind now I am a litre guy. I used to think in Imp gallons per mile, but that was because my father spoke in those terms. But with Kilometers on the signs and litres at the pump it doesn't make much sense to use gallons, or miles.

I keep a bookmark with a conversion calculator to get it making sense.....especially when Tapage starts talking gallons to the KM....LOL

 

[brownbear]

Hey
I was not wishing to start an International debate on historic systems of measurement!!
I was just pointing out that there is a difference and I have seen this mathematical mistake made before, having said that it is very common to compare vehicle mileage with the US system? and with great displeasure (brownbear) I now see the advantage of the metric system!!!
BTW (old) I resemble that remark!!

debates are what we do best on here.....so no worries.

Yah many Canadians who were schooled before 1975ish all think in standard units, such as imperial and what not.

I'm a mis match of units. I work on planes that have all measurements in inches, measure fuel in pounds, and feet for altitude. But in my car I speak KMs and litres.

But I consider my weight in lbs too. Kilos are not in my frame of thinking. Maybe my kids will think in all metric.

 

[freebie]

Hey Brownbear
When you see a metric road sign on the Hart Highway do you still mentally convert to miles??

If so Cool, were both in the 75ish bracket??

 

[brownbear]

Hey Brownbear
When you see a metric road sign on the Hart Highway do you still mentally convert to miles??

If so Cool, were both in the 75ish bracket??

No I am thinking in KMs really only. Have owned a few vehicles with a miles speedo, so I do convert then.

But I was born when the conversion for the country began....

Cheers, BB

 

[tntoyota]

Ok, now I'm starting to get really worried...

last fill up I put in 66L. Drove 520Km then put in 69L - safe to say I used roughly 69L to drive that 520km

520/66 = 7.879 km/L
100/7.879 = 12.7 L/100 km

OR

66/520*100 = 12.7L/100km


12.7/3.78 = 3.36 G/100 km
or 3.36G/62.5Mi


62.5/3.36 = 18.6MPG

31 series tires = 5% error, 18.6 *1.05 = 19.5 (ok, so it's not 18mpg)

Now, My 8Cyl, 7.3L F350 with 10 times the balls can get 18Mpg, WHY am I only getting this out of the little wimpy 3B?

I'm keeping it under 2200RPM, most driving is on the highway, I'm not lugging the engine.... I don't have a massive fuel leak, and I'm not towing. Where is it all going? - PLEASE help!
**EDIT** - Oh, there is no black smoke either.... incase someone thought I might be overfuelling **

My opinion, Disregard if out of line.


I think I've read allot of posts and nothing as to what gear you are running,


isn't that a factor?.....


1: For some reason I don't think you base line is accurate (looks like I saw some speculation, how do you know your tires aren't in fact accurate and your math off by 5%?).

and 2: I'm not Toyota Diesel savvy but ain't 2200rpm a little high?


You running a 31" tall tire?

 

[MrMoMo]

I dunno, count me as one of the others. If I'm talking gallons it's because I'm talking to someone who doesn't relate well to Litres. By definition that means an American.

Same here...

Circular Mils

HEY! I still use those! (wire size)

 

[MrMoMo]

I think I've read allot of posts and nothing as to what gear you are running,


isn't that a factor?.....

I have stock gears, so not a factor for me. Regardless though, I am comparing road speed to indicated speed (and hence odometer reading). Changing gears may change that ratio, and eliminate the needed correction factor.

1: For some reason I don't think you base line is accurate (looks like I saw some speculation, how do you know your tires aren't in fact accurate and your math off by 5%?).

My indicated speed to actual speed is not a calculated number, it is a GPS reading compared to a speedo reading....

and 2: I'm not Toyota Diesel savvy but ain't 2200rpm a little high?

If it is, please let my 3B know, so it can get back in line and start using less fuel.

As a reference, The marine Diesels I use rev the following...

4.2L redline = 3900 RPM
5.9L redline = 3000 RPM

I think the lil old 3.4L can handle it.

You running a 31" tall tire?

I was, but now I'm running 33's, and my error factor is now 10% (not calculated, measured with GPS). When my speedo reads 100km/hr - my GPS says 110. = 10%

Bruce

 

[brownbear]

and 2: I'm not Toyota Diesel savvy but ain't 2200rpm a little high?

nope!