Adjusting fuel on B engine (1 Viewer)

[Rusto]

My 75 BJ40 has been rolling coal for some time now when I "accelerate" at a "rapid" pace. I can feather the throttle and look in the rearview mirror to mitigate that somewhat, but I'd prefer to have more pedal to work with and not have it dump black smoke everywhere in my wake. It's really bad. It's bad mostly because I drive around at 6,500' and higher so the fuel/air ratio is off and I'm belching out unburnt fuel.

I'm working on getting an HAC installed and I've collected most of the parts, but that's probably a winter project at this point.

In the meantime, I've decided to turn down the fuel a bit until I can add HAC. The lowest altitude I'll be at is 6,500 at this point. With the help of MUD, I identified where I do that (see picture) and I turned it down a 1/4 turn yesterday. That, and a fresh air cleaner and I've seen a noticeable improvement. However, I want to turn it down another 1/2 turn and try again, but it's really tight, so much so that I felt like I was going to twist it off. And lord help me if that were to happen.

Anyway. My question to you... should I be able to turn down the fuel as much as I need to, or does it eventually stop and not allow me to turn it down any further?

 

[duncanrm]

That very much looks like the pump bleed screw.. not the wide open throttle fuel screw.

Do you have a much wider photo of your pump? It'll be the screw that the fuel control lever rests against.

 

[Rusto]

Thanks @duncanrm
Here's the pic and the arrow where perhaps it is?
I have the FSM for the B engine, but haven't been able to identify it in there.
A

I greatly appreciate the help. I did get OEM shifter knob, OEM windshield wipers and OEM radiator cap installed. I love those easy and cheap OEM updates.

 

[4Ruster]

Did you notice a bit of a power drop at all? I feel like if I were to drop my fuel screw a bit it would make the pedal feel “weaker” because you now have to push it farther to get the same fuel injected. Or am I wrong?

 

[Rusto]

@4Ruster - I fully expect to need to put more foot into the pedal. Right now, I'm about 1/3 of the way down before it starts pouring black smoke out, so I want to have more pedal to play with and also be able to accelerate a bit w/o it smoking.

With that said. Eureka! I have found it. I repeat, I have found it! The fuel adjust screw is tucked down in there to say the least, but I found it.
Looking forward to turning down the fuel a bit to compensate for the less O2 I get at 6,500.

 

[bj70bc]

or you could turbo it......

 

[Rusto]

Would love to add a turbo. Someday. Once that occurs, I'll know how to turn the fuel back up at least

 

[duncanrm]

Would love to add a turbo. Someday. Once that occurs, I'll know how to turn the fuel back up at least

Your B has been a solid performer over many years.. let her see out her remaining days without flogging her to death with a turbo

Well done on finding the fuel screw Any chance of a few more pump photos? Has it got an oil dipstick?

 

[Rusto]

Yeah, turbo is waaay down the list. Plenty of other stuff to do and I don’t really want to go faster than 100kph in this contraption anyway.

Here’s another pic. I love Toyota diesel porn, so lmk if any others you want.

And when I’m under the hood there are two dipsticks in there

 

[Rusto]

And pic

 

[bj70bc]

Yeah, turbo is waaay down the list. Plenty of other stuff to do and I don’t really want to go faster than 100kph in this contraption anyway.

dont worry .... you wont, i still cant, more of an efficiency and acceleration thing

 

[4Ruster]

dont worry .... you wont, i still cant, more of an efficiency and acceleration thing

If a turbo will let me hold my speed going up a hill then a turbo it is. Love going from 60km/h to 45km/h whenever I go up the hill to my parents place.

 

[duncanrm]

If a turbo will let me hold my speed going up a hill then a turbo it is. Love going from 60km/h to 45km/h whenever I go up the hill to my parents place.

See if they can move to the same altitude as you.

 

[Rusto]

That's a crappy picture. I hope to get some time tomorrow or Thursday night to adjust the mix, so maybe I'll get a better one then. Otherwise, it'll have to wait until this weekend.

 

[duncanrm]

That's a crappy picture. I hope to get some time tomorrow or Thursday night to adjust the mix, so maybe I'll get a better one then. Otherwise, it'll have to wait until this weekend.

Thanks.. a good set of B Pump Photos would be great to have on record.

 

[Rusto]

More pics! These two are better. And to answer your question again @4Ruster after thinking about it more. I don't think I'll lose that much power, if any. One, I'll be able to put more pedal into it, but more importantly, the black smoke is unburnt diesel that isn't giving me any power anyway. My thoughts are that if I get it to where it's smoking very little, it'll be burning more efficiently w/o losing much power. Maybe better mpg.

Anyway, to the pics!

 

[duncanrm]

Sweet little pump, thanks for the pics. Keen to hear back on how your smoke reduction efforts turn out.

 

[Rusto]

Operation Fuel Screw has been a success.
19MM socket and a long and short flathead screwdriver is all that’s needed.

The nut that holds everything in place broke loose easier than I thought it would, this caused me to to lose track of where the screw was a bit.
I think I turned it down about a turn and a half, initially. It really doesn’t take long, just a few minutes with most of that time trying to get the wrench on the nut.

(Be sure to disconnect the battery, work is done down by the starter and you don’t need a random spark)

Anyway. No smoke! And more fun with the pedal
It felt a little fuel starved so I went back a quarter turn (counter clockwise) and it’s better, but still lacks a tiny bit of power.

I’m going to add a little fuel 1/4 turn at a time until I get just a little smoke on hard acceleration and figure I’ll be there.

Hopefully be able to find a few minutes tomorrow.

It sure is nice to put the pedal all the way down, have it accelerate smoothly and not smoke out everything behind me.

(One more quarter turn of fuel and it’s the best it’s run since I bought it. Just a touch of smoke upon full acceleration. Enough to know it’s a diesel. )