2L Fuel adjustment screw (6 Viewers)

[keving]

Im working on an 84 2L 4WD pickup. 250k. Someone had messed with the fuel screw in the past to get some "more power" out of the poor little engine. Smoking more then it should now and high EGT's. I realize the injectors are likely due for a service, but I'd like to return the fuel settings to stock and see where that takes me.

Now, I would like to turn it back down but cannot seem to find it. I have had a few L series engines but never had to mess with the injection pumps too much.

Any tips would be great,
Thanks

 

[yotahed]

On the top cap of the pump at the back on the engine side, there will be a bolt with a 12mm lock nut. There might be a tamper cover still present, but if someone has already messed with it, should be easy to spot.
Undo the lock nut while holding the bolt/screw with a flathead driver, and turn out a 1/4 turn at a time to see what you get.
Take note of how many turns or youll be hunting for awhile to get it back. A little does a lot.

 

[keving]

Hey thanks for the tip! I will be checking it out in a couple hours

 

[yotahed]

Its the one sticking off the back of the top cover in the pic. Letter K.

 

[yotahed]

Just dont mess with any of the other screws or youll be....... Screwed lol.

 

[keving]

Turned er back a quarter turn and took it for a drive. There is less smoke then before and no noticable loss in power. This is where it is going to stay!!!

And thanks for that very informative photo of the pump!
Regards

 

[yotahed]

There you go. Glad to help Sir.

 

[DanRabey]

What is the result if it over fueling? I'm assuming loss of fuel economy and lots of black smoke

 

[seatosummit]

Anybody have advice on how the heck to get a wrench on that adjustment screw? Its really tight in there and my attempts thus far have failed on my '87 2L-T in a LJ70.

Assuming I am looking at the correct screw?

 

[GTSSportCoupe]

Anybody have advice on how the heck to get a wrench on that adjustment screw? Its really tight in there and my attempts thus far have failed on my '87 2L-T in a LJ70.

Assuming I am looking at the correct screw?

View attachment 3463780

View attachment 3463781

Why do you want to adjust it?

If you want more power, you're much better off raising boost a bit (boost controller), and making some minor adjustments to the boost compensator if needed. That way you still run safe AFR, clean burn, but make more power. But it's also hard to get at adjustments there.

If you do mess with the fuel screw, take some careful pictures, or mark with some paint so you can put it back how it was if you're not happy.

 

[seatosummit]

Less power, less fuel is what I am after. I am blowing black smoke under load and have already cleaned the injectors, replaced fuel filter, etc.

I'm fairly convinced that somebody has tightened the screw before more, so I would like to back it out and see if the over fueling persists.

Definitely wouldn't tighten the screw without EGT probe (which this truck does not have).

 

[Adam R]

I converted a 2L to a 2LT with an intercooler years ago. Still have the truck, although it's in storage for now in another state. That clips looks like an anti-tamper device that needs to be cut off. Also, It looks to be on the boost compensator. If I remember correctly, the fuel enrichment screw is on the side of the pump itself. If you are blowing smoke, I'd check to see what you are getting for boost first. I was running my 2LT on the hot side with 21-22 lbs of boost. I was well over what Toyota ever set them up for, but I ran that truck for 15 years at those boost levels without issue. It would smoke at low rpm/low boost, but would quickly clean up once on boost. EGT's were kept at 1200 F or below.

 

[Erenik]

I converted a 2L to a 2LT with an intercooler years ago. Still have the truck, although it's in storage for now in another state. That clips looks like an anti-tamper device that needs to be cut off. Also, It looks to be on the boost compensator. If I remember correctly, the fuel enrichment screw is on the side of the pump itself. If you are blowing smoke, I'd check to see what you are getting for boost first. I was running my 2LT on the hot side with 21-22 lbs of boost. I was well over what Toyota ever set them up for, but I ran that truck for 15 years at those boost levels without issue. It would smoke at low rpm/low boost, but would quickly clean up once on boost. EGT's were kept at 1200 F or below.

Hello Adam, can you tell me what kind of intercooler and brand did you install in your car? I have a LJ70 1988 2.4 TD I’m im trying to get a intercoller online.Thanks

 

[Adam R]

Hello Adam, can you tell me what kind of intercooler and brand did you install in your car? I have a LJ70 1988 2.4 TD I’m im trying to get a intercoller online.Thanks

I built a custom bumper for my truck and incorporated an audi intercooler from the junkyard. I would try to fit the biggest one you can with the space you have available.

If you search by my user name, you can probably find some older posts from me related to this truck.

Good luck!

Adam