Carb NOT Tuning (1 Viewer)

[dannyvp]

I've been messing with this issue for over a year now, and I've finally had enough.

2F engine - desmogged - City Racer Carb

My Issue:
Carb will not tune and the truck seems to run lean. At 70% peddle and higher the truck runs ok, at lower RPMs (under 2500) and peddle depressed around 70% or less the truck stumbles a lot. It runs horribly which includes low power and lots of bucking or surging. Sometimes when you let off the gas you will hear a backfire.

What Ive done:
Otramm style carb tuning. When you adjust the fuel screw on the back of the carb the RPMs do not increase. You have to adjust the idle screw to adjust the RPMs.
Timing is set to ~11.
Unhooked the charcoal canister because I had pressure in the tank.
Had a new manifold gasket put on because of a vacuum leak. The vacuum is around 20-22.
Reset carb and started over several times. (adjusting screws back to normal)
New fuel filter
New fuel cap
New fuel pump and gasket
Carb has fuel in the site window, Fuel filter has fuel flowing through it.
Engine idles great.

Ideas on how to fix this?

 

[OSS]

Not to say that the following suggestion is the issue with your carburetor, but not a couple members here found metal swarf filings/debris inside their brand new (yet malfunctioning) City Racer carb.
I wouldn’t rule out that possibility.
Just because that carburetor is made in Japan instead of China doesn’t mean it’s exempt from poor quality control.

 

[dannyvp]

Not to say that the following suggestion is the issue with your carburetor, but not a couple members here found metal swarf filings/debris inside their brand new (yet malfunctioning) City Racer carb.
I wouldn’t rule out that possibility.
Just because that carburetor is made in Japan instead of China doesn’t mean it’s exempt from poor quality control.

This is my 2nd city racer carb. The first one had plastic all in the screen when I had issues with it and tore it apart. City racer did send me the second one bc of the issue.
How do I rule something like this out, without....tearing it apart?

I can't think of a lot of issues that would cause something like this....but I'm not a cruiser guru either.

 

[OSS]

How do I rule something like this out, without....tearing it apart?

You know the answer - and it’s expensive

(hint: everyone who owns an FJ60 at this stage of the game should own two carburetors)

 

[dannyvp]

You know the answer - and it’s expensive

Is that a sniper? Im worried i will still have an issue for some reason if I do that.

I did just dig out my OEM carb and I'm going to install it and see what happens. (I took it off bc of a small fuel leak and I was updating other items so I installed a new carb)

 

[CruiserTrash]

@BrownPig Might be able to provide some guidance. He's been round and round with non-OEM carbs.

 

[OSS]

I did just dig out my OEM carb and I'm going to install it and see what happens

Good idea. Definitely report back here with the outcome.

When I said “expensive”, I meant another functioning carburetor.

 

[FirstFJ60]

Have you torn down the carb to investigate? While you are in there might was well rebuild it. easy to do.

 

[bhsdriller]

Yep you already have the OEM i'd do a rebuild

 

[cps432]

No smog? Sniper. No brainer. Especially if you’ve been chasing it for a year and have no emissions. SNIPER TIME!! Seriously. It’s a better upgrade than an OME lift and an H55F with a diff re-gear. But if you combine all those with 33” tires you’ll be very happy.

 

[dannyvp]

Have you torn down the carb to investigate? While you are in there might was well rebuild it. easy to do.

Its a pretty new carb, i didnt want to tear it apart.

 

[dannyvp]

No smog? Sniper. No brainer. Especially if you’ve been chasing it for a year and have no emissions. SNIPER TIME!! Seriously. It’s a better upgrade than an OME lift and an H55F with a diff re-gear. But if you combine all those with 33” tires you’ll be very happy.

my luck i would be the guy plagued with problems. But I'm really really thinking about it.

 

[ro11dice]

You know the answer - and it’s expensive

(hint: everyone who owns an FJ60 at this stage of the game should own two carburetors)

CityRacer carb wouldn't be an option for me since I'm in California and it's for desmogged 60s. But as a 2nd carb, would I be able to use it as a temporary solution even with my 60 smogged?

 

[OSS]

Yes.
Install a new CityRacer Japanese carb and use it exclusively between tests. Then get your original Toyota carburetor rebuilt and fully checked out and tested by a professional 2F carb guru and use it only for tests.

Is one solution.

 

[cwwfj60]

my luck i would be the guy plagued with problems. But I'm really really thinking about it.

Look up the “green wire mod” I think it’s called…. you might be losing your power signal to the carb fuel solenoid…the only thing electronic involved here. You can easily bypass this for testing….I’d highly recommend double checking this before proceeding.

 

[ChaserFJ60]

I've been messing with this issue for over a year now, and I've finally had enough.

2F engine - desmogged - City Racer Carb

My Issue:
Carb will not tune and the truck seems to run lean. At 70% peddle and higher the truck runs ok, at lower RPMs (under 2500) and peddle depressed around 70% or less the truck stumbles a lot. It runs horribly which includes low power and lots of bucking or surging. Sometimes when you let off the gas you will hear a backfire.

What Ive done:
Otramm style carb tuning. When you adjust the fuel screw on the back of the carb the RPMs do not increase. You have to adjust the idle screw to adjust the RPMs.
Timing is set to ~11.
Unhooked the charcoal canister because I had pressure in the tank.
Had a new manifold gasket put on because of a vacuum leak. The vacuum is around 20-22.
Reset carb and started over several times. (adjusting screws back to normal)
New fuel filter
New fuel cap
New fuel pump and gasket
Carb has fuel in the site window, Fuel filter has fuel flowing through it.
Engine idles great.

Ideas on how to fix this?

Here's a list from a manual i had

fj60 Carb adjust screws, what do they do?

There are four of them. I have till Wed. If cant do it i will bring it to MArk in Burbank.

forum.ih8mud.com

 

[dannyvp]

Here's a list from a manual i had
View attachment 2929090

fj60 Carb adjust screws, what do they do?

There are four of them. I have till Wed. If cant do it i will bring it to MArk in Burbank.

forum.ih8mud.com

I think everything points to my carb, my reasoning for that thought is, the fuel mixture screw does not raise the RPM's in any way.
I also wonder if the vacuum to my carb could be incorrect. I hope Friday is nice outside so I can check that.

 

[dannyvp]

Yes.
Install a new CityRacer Japanese carb and use it exclusively between tests. Then get your original Toyota carburetor rebuilt and fully checked out and tested by a professional 2F carb guru and use it only for tests.

Is one solution.

After i do this this replacement test, this may be the route I go, rebuild the original and use the CR for in between time..

 

[dannyvp]

Look up the “green wire mod” I think it’s called…. you might be losing your power signal to the carb fuel solenoid…the only thing electronic involved here. You can easily bypass this for testing….I’d highly recommend double checking this before proceeding.

I do have a new solenoid on the truck, however I'll try this and make a plug connection and ground the green wire, just to see what happens.

 

[klinetime574]

This sounds more timing related to me. I’d double check your timing. Mine has been set to factory and that’s where I leave it. Desmogged, ran my OE carb that way and now my Sniper. I didn’t even recheck my timing before I finished the install and drove to CO from IL.