FJ60 2F Only runs smooth with the Choke on it (1 Viewer)

[DutchFJ60]

Hi i'm Robert from the Netherlands.

I have a FJ60 with the 2F engine in it but i got a problem. Because here in the netherlands they are not known with the 2F engine i will try it here.

My FJ60 is backfiring al the time when i dont use the Choke. When i use the choke it really runs great! But if i turn the choke back and the engine
is idling at 700 RPM it just keeps backfiring. Does somebody here is known with the problem?

Sorry for the bad english!

Thx

 

[OSS]

Backfire and After-burning are two different things with opposite causes.

Backfiring is when an explosion happens in the intake manifold and almost always is caused by a vacuum leak which creates an overly lean air-fuel mixture.

After-burning (which most people call backfiring) happens in the exhaust pipe and is always caused by unburned fuel getting into the exhaust then igniting on the hot metal. It often sounds like a gun shot.
It’s caused by an overly rich air-fuel mixture.

If you’re hearing popping out the exhaust pipe at idle, the idle mixture is likely set way too high. There’s an idle mixture screw on the inboard side of the carburetor that’s used to set the idle mixture — but you shouldn’t touch it until you’ve read the Toyota 2F manual for instructions.

There were different carburetors used on 2F engines depending on the country, so it’s hard to make a precise suggestion without seeing pictures of your carburetor and engine compartment.

 

[fjc-man]

Can you post pictures of the engine?

 

[Spike Strip]

What OSS said ^^

Most likely you need a Carburetor rebuild or new carburetor.

If you pull the choke all the way on and it runs smoothly, then petrol is coming from the idle circuit only. You may have petrol somehow leaking out a venturi or a port when choke is off.

Toyota still sells a new World-spec carburetor for the 2F. There are also some cheap Chinese copies as well as Japanese-made ones. You should check you local sources first, or look for a rebuild kit if you want to try that first.

Pix so we know what carb you are running. The USA spec carb is quite different from the rest of the world 2F due to smog.

Welkom

 

[DutchFJ60]

Wauw! Thanks for al the information. The fj is from the USA and the smog system is still working.

@OSS the car is firing in the exhaust there are flames coming out. So I think it gets to much fuel.

 

[OSS]

At this point in the game (35 year old vehicle) everyone who owns a FJ60 should ideally own two carburetors: one new (or rebuilt) sitting on a shelf ready to go and the current one in the truck.
I’d definitely take @Spike Strip ’s advice and install another new carb. Then with time permitting, get the original one rebuilt.

 

[Spike Strip]

Looks like an unmolested USA truck - How did it end up in NL ?

If you can remove the smog equipment, it is a good thing at this point and you can then run a new carburetor. Are you at sea-level or under 4K Foot elevation? Plenty of threads here on how to properly desmog that engine.

Also, that large pipe coming off the top of the air cleaner looks unplugged. It's allowing unfiltered (dirty) air directly into the engine. Very bad.

 

[fjc-man]

There is a tag on the carb secondary diaphragm the says “carburetor exchange rebuilt”. How long ago I wonder.

 

[DutchFJ60]

@OSS and @Spike Strip Thanks for the the info and the help.! I'm going to search an original one . Do you think it will help if i try to adjust the mixture for the time being? And do you know where to find the 2F Manual for adjusting the Carburetor? I saw a Youtube Video but this was an FJ40 i dont know of this is the same?

@Spike Strip - i bought it from a guy in Belgium it was standing in his garage for 10 years and he imported it from the US. He wanted to restorate it but he didnt had time for it. And now i'm the happy owner. I didnt run when i bought so it is running but nog how it supposed to be .

@fjc-man Yeah i see it now! I'm wondering if this one is rebuilt ones because it looks kind of original and the screws look like not toucht.

 

[cps432]

Cruisermanuals.com should have all the factory service manuals you will ever need. I believe you will find the carb tuning information in the 2F engine service manual. Originally, for the USA trucks, Toyota made the adjustments in the factory and put a plastic cap on the adjusting screws to meet government regulations and keep people from tampering with it. I doubt the cap is still in place after 30+ years. It’s a fairly easy process, but it’s more of an art than an exact science.

 

[OSS]

And do you know where to find the 2F Manual for adjusting the Carburetor?

Here’s a link to a spot where someone uploaded several 60 series manuals. Download all of them because stuff like this has a tendency to disappear.

FSM - Google Drive

 

[Spike Strip]

@DutchFJ60

That carburetor has been rebuilt: There's a white 'Exchange' sticker on the secondary diaphragm housing. My guess is it's a bad rebuild.

Adjusting the carb mix screw will probably not do much, if there is so much unburned fuel that there are flames out the tailpipe, it's something else. Fuel is dumping.

You won't find a direct replacement for that USA spec carburetor in Europe, unless you get very lucky; It's USA only with smog controls. Someone here may be willing to ship you a carburetor as a spare.

If you want to keep it stock, you will have to rebuild or have rebuilt.

Have you checked the TIMING ?

 

[ntdb]

Make sure your engine fuse is good and your idle control solenoid is working. It’s simple to test and can cause the behavior you’re experiencing. It’s on the carb and it should click audibly when you cycle the key on and off.

 

[DutchFJ60]

@DutchFJ60

That carburetor has been rebuilt: There's a white 'Exchange' sticker on the secondary diaphragm housing. My guess is it's a bad rebuild.

Adjusting the carb mix screw will probably not do much, if there is so much unburned fuel that there are flames out the tailpipe, it's something else. Fuel is dumping.

You won't find a direct replacement for that USA spec carburetor in Europe, unless you get very lucky; It's USA only with smog controls. Someone here may be willing to ship you a carburetor as a spare.

If you want to keep it stock, you will have to rebuild or have rebuilt.

Have you checked the TIMING ?

Yes the timing was the first thing that I did.

 

[fjc-man]

 

[Skellibert]

I got a replacement carb from ebay for mine (3F carby in Australia) - apart from an issue with the vacuum hoses not fitting the "new" carby base (ended up swapping the base back to the original) it has been running well.
Can't remember the provider, but I am almost certain it is a Chinese copy. Should be available though.
Sounds to me like an adjustment won't do much worthwhile. You need to at least give the thing a serious clean.
But "service kits" are available.

 

[DutchFJ60]

Hi Guys,

I'm back! I put the car to the side for a month because i had other things to do. But i replaced and a just some parts the last week but its stil not running perfect!
The problem of the the after burning is fixed! . @ntdb the solenoid was the problem i think! It didn't click but i also dit not got any power on the cable. So i made a bypass and now the solenoid clicks but its ON for all the time, i dont know of this is a problem? It stopped after burning now when the choke is off! So i'm happy with that.

The car runs now perfect but there is still 1 problem!

If i drive the car and it doesn't matter what speed but if the engine is warm and i keep the car on a same speed like 40mph then the car
shocks a little bit! So i took the distributor cap of and the rotor and they were old. I thought this was the problem but it didn't helped.

because the engine is running great when its idling and when i give it full throttle i don't think the problem is in the SMOG system? But maybe
i'm totally wrong!

I will make a list what i did till now! :

1. Set Ignition Timing Correct
2. Replaced Distributor cap and the rotor.
3. Adjust the mixture of the carburetor (But the CO what comes out of the exhaust is still to high on the tester)
4. Ultrasonic cleaned the carburetor and replaced al the gaskets.

Does anyone has some more tips and tricks .

 

[Gretsch]

If i drive the car and it doesn't matter what speed but if the engine is warm and i keep the car on a same speed like 40mph then the car
shocks a little bit!

What's this mean "Shocks a little bit"? Like bucks as if its stopping and then going?

 

[DutchFJ60]

Sorry for the bad english! Right thats what i meant.

 

[Gretsch]

You mention re-wiring your ICS somehow with a bypass. I've had this sort of bucking happen with bad grounds on the factory ICS wiring. The ICS in a factory setup is designed to hold open when energized to allow fuel flow and close to prevent unburned fuel from travelling into the exhaust system on decel and help prevent run-on after ignition shutoff. If the ICS opens and closes intermittently while driving, it can temporarily cut fuel flow causing the engine to start and stop the way you describe. Not sure on the details of how you wired it up but maybe something to look at. Maybe your bypass wiring is faulty closing the ICS as you drive? When it happened to me it was quite a violent experience. Literally like hitting speed bumps at highway speeds. I have also had a similar experience when my coil gave up the ghost at highway speeds. That was more a loss of engine power and an after-burn situation. Similar but different. Just my experience.

So i made a bypass and now the solenoid clicks but its ON for all the time, i dont know of this is a problem?

When you say 'ON all the time', I am assuming you mean while the key is on and not wiring straight to the battery somehow.