1987 FJ60 Won't Stay Running/Idle After Start-Up (2 Viewers)

[socalsixty]

SOLVED! (Kind of?) See post on 2/17/22.

Hey guys,

First post here in the tech section. Quick background to better understand what I'm dealing with:

I bought this nearly all-stock '87 60-series about 3 years ago from the original owner's family here in San Diego, CA. Truck currently has about 290,000 miles, which is up there but still a strong runner. Drove it for about a year and a half (with zero issues) before it failed emissions and has been off the road since. I would start it weekly and drive it around the neighborhood to keep things fluid. One day it would not start, and decided to have a reputable Land Cruiser company perform a rebuild on the carb. Now that I've had some time (and money) to dive into it, a few issues have come up that have left myself and my Toyota tech buddy pretty stumped.

NOTE: The choke issue below did not arise until the carburetor was rebuilt.

With everything connected and normal, the truck starts immediately (regardless of engine temp) and runs strong for about 5 seconds, before quickly dying. The majority of my troubleshooting has been done in 60-80 degree weather, which I understand can have an influence on the lower (pink) bi-metal vacuum switching valve that is coolant-temp operated, at 41 and 66 degrees fahrenheit. Essentially, it seems that the choke opener (not to be confused with the choke breaker) is opening immediately upon startup and overriding the manual choke due to an unknown reason. Is this normal? When removing the choke opener vacuum line, the truck will run for about 15-20 seconds before the choke breaker kicks in and causes the truck to die. With BOTH the choke breaker and choke opener vacuum lines removed, the truck will run fine at a higher idle with the choke manually closed. Once the choke is open, whether that be vacuum or manually controlled, the truck dies. However, it WILL idle with the choke fully open while spraying starting fluid into the carb. Fuel is getting into the carb and sits at the center of the sight glass on the front. At this point, we still believe we have a fuel delivery issue based on the troubleshooting performed. We went through the majority of the emissions manual testing the valves, switches, etc with no luck.

I recently replaced:
- Fuel pump
- Fuel filter
- ALL vacuum lines (referencing the factory 2F emissions control manual in the process)
- Carburetor Rebuild
- Fuel cut solenoid
- Both bi-metal vacuum switching valves
- Distributor vacuum advance diaphragm (old one did not hold vacuum)
- Distributor cap and rotor
- Spark plug wires
- Spark plugs
- Ignition coil
- Re-timed the truck to factory spec

I know the folks on this forum are a plethora of information and tech knowledge, so any and all comments are welcome and appreciated. PLEASE feel free to tell me I'm a dummy and overlooking something simple! Thanks!

 

[g-man]

The 2f Emissions FSM shows how to check the choke opener and choke breaker systems. If you want me to copy and paste the pages here I can.


sounds like a fuel delivery issue or a vacuum leak large enough to stall the engine. It's rare but there is such a thing as an internal (to the carb) vacuum leak caused by a crack in the carb housing. There are vacuum passages inside it. Also if your rebuilder omitted a piece internally this can cause a vacuum leak and stalls without the choke closed.

the easiest thing to do at this point is to use a known to be good carb and install it and see if that works. If so, go back through the offending carb and go though the FSM one step at a time and make sure everything is there and in the right place. Check the fuel jets, the float setting, the needle and seat, EDIT: make sure the vacuum passage bolt is in place with a new gasket.

 

[g-man]

 

[OSS]

I’m with @g-man on this.
Just because a carburetor got “rebuilt” doesn’t mean it’ll function properly. There’s like 37 ways to screw up the carburetor when taking it apart and putting it back together.
If you didn’t have the carburetor rebuilt by a well known land cruiser carburetor specialist who works on these for a living and has plenty of good references, (Jim C) the carburetor is still suspect.
And even still - something can go wrong.
A 2F that starts fine then conks out after a few seconds is starved of fuel. Since spraying starter fluid down the carb throat will keep it running- that’s definitely fuel starvation (vs ignition problem).

At this point I’d go for the nuclear option since you’ve already replaced a lot of stuff.
I’d buy a brand new Japanese (non USA, non-smog legal) carburetor from City Racer, install it and get your truck running.
Then get your malfunctioning USA original carburetor fixed properly.

Aftermarket 2F / 1.5F Carburetor for Land Cruiser FJ40 FJ60 - Made in Japan

High quality aftermarket 2F / 1.5F carburetor for desmogged applications. Same as OEM part # 21100-61012. Made by Fuji Japan. Notes: If your vehicle is 1976 or newer and your vehicle is registered in California or other areas with smog check requirements, you cannot use this carburetor. We...

www.cityracerllc.com

 

[socalsixty]

Thanks for the info guys! Much appreciated. Do you know how soon the choke opener is supposed to pull vacuum and open? It seems like it’s instant in my case, even from a “cold” start (in 70 degree weather). Next step is going to be ensuring the choke breaker and choke opener are working correctly, and then using a smoke machine to determine where any vacuum leaks may be. Not sure if this will show any leaks internal to the carb, but it’s a start. I have a hard time believing a massive vacuum leak developed during the time the carb was rebuilt, so I’m almost certain the issue is internal to the carb (poor rebuild). Either that or the choke opener is operating too soon.

 

[CardinalFJ60]

I had a similar issue and it turned out to be gunk in the little screen/catch thingie inside the carb. (?) it was fine under load, but the stuff would settle in and limit the fuel at idle.

 

[OSS]

Since you said that the engine will die after starting even if it’s warm, that pointing to it not being a Choke Opener issue. When the stock 2F engine is warm, the Choke Opener opens the choke plate the instant there’s any vacuum, disabling choke but allowing increased throttle.

If the Choke Opener was opening too quickly, it wouldn’t affect warm starting at all, because it’s supposed to open very fast when engine is warm. It also wouldn’t affect subsequent idling because the choke would automatically be pulled open.

The Choke Opener is a stupid device (like almost everything in the 2F). It’s only triggered by the BVSV located in the thermostat housing when the coolant is above 66°F.

If you want to see for yourself, you can rule out the Choke Opener as a suspect when the engine is cold or warm just by pinching off the vacuum hose that connects to the CO vacuum actuator on the carb.
That’ll take it out of the equation.

Definitely get a vacuum gauge hooked up to your manifold.
Required equipment on this vehicle.

 

[socalsixty]

I had a similar issue and it turned out to be gunk in the little screen/catch thingie inside the carb. (?) it was fine under load, but the stuff would settle in and limit the fuel at idle.

Gotcha. I have the issue at idle, and as soon as I touch the throttle it wants to die. Regardless of the position of the choke. Do you happen to remember where that piece may be? Going to dig into it again in the next day or two.

 

[socalsixty]

Since you said that the engine will die after starting even if it’s warm, that pointing to it not being a Choke Opener issue. When the stock 2F engine is warm, the Choke Opener opens the choke plate the instant there’s any vacuum, disabling choke but allowing increased throttle.

If the Choke Opener was opening too quickly, it wouldn’t affect warm starting at all, because it’s supposed to open very fast when engine is warm. It also wouldn’t affect subsequent idling because the choke would automatically be pulled open.

The Choke Opener is a stupid device (like almost everything in the 2F). It’s only triggered by the BVSV located in the thermostat housing when the coolant is above 66°F.

If you want to see for yourself, you can rule out the Choke Opener as a suspect when the engine is cold or warm just by pinching off the vacuum hose that connects to the CO vacuum actuator on the carb.
That’ll take it out of the equation.

Definitely get a vacuum gauge hooked up to your manifold.
Required equipment on this vehicle.

I’ll try this out as soon as I’m back under the hood. I think because of the climate I’m in, the BVSV that controls the choke opener is irrelevant since the coolant temp won’t drop below 60 degrees or so. If that’s the case, it’s definitely a fuel delivery issue. I’ll report back! Thanks again everyone

 

[2mbb]

both the choke breaker and the choke opener only operate on the choke plate. Neither one will effect the fast idle adjustment. You consistently use the word "idle" and it 's hard to tell if this is at the fast idle setting (with choke knob pulled out) or the normal idle setting.

So, after installing the rebuilt carburetor, did you make any attempt to adjust the idle mixture, idle speed, and fast idle speed screws. Without a proper mixture and idle speed (or fast idle speed with choke knob pulled out) the carburetor may not keep the truck running. It almost seems like your idle circuit is not providing enough fuel and the engine is relying on the primary circuit to provide the fuel via closing the choke plate. do a search for "lean drop" and you will find instructions how to adjust mixture and idle speed.

While you are at it, you should also check that the fuel level is correct by looking in the sight glass.

Registering your truck in California almost requires you to have a copy of the 2F emissions manual Toyota publication RM36043. You can purchase a reprint from some of the Land Cruiser vendors or find a PDF version to download here on MUD.

 

[socalsixty]

both the choke breaker and the choke opener only operate on the choke plate. Neither one will effect the fast idle adjustment. You consistently use the word "idle" and it 's hard to tell if this is at the fast idle setting (with choke knob pulled out) or the normal idle setting.

So, after installing the rebuilt carburetor, did you make any attempt to adjust the idle mixture, idle speed, and fast idle speed screws. Without a proper mixture and idle speed (or fast idle speed with choke knob pulled out) the carburetor may not keep the truck running. It almost seems like your idle circuit is not providing enough fuel and the engine is relying on the primary circuit to provide the fuel via closing the choke plate. do a search for "lean drop" and you will find instructions how to adjust mixture and idle speed.

While you are at it, you should also check that the fuel level is correct by looking in the sight glass.

Registering your truck in California almost requires you to have a copy of the 2F emissions manual Toyota publication RM36043. You can purchase a reprint from some of the Land Cruiser vendors or find a PDF version to download here on MUD.

Thanks for the info! The fast idle was adjusted to 1500rpm after the truck came to temperature. The idle I’m referencing is with the manual choke engaged (lever pulled out), as I’m not able to get it to run otherwise. Even so, it dies as soon as the choke plate opens up within 5 seconds of firing.

I have the mixture set at a base setting now of two full turns out, with the regular idle (as best I can) set at about 650-700rpm and the fast idle at 1500rpm. To my knowledge, this is the factory setting for idle and fast idle (as best I can tell). But I’m going to start over regardless to ensure everything is within spec.

The fuel level is dead center in the sight glass, and (thanks to this forum) I was able to find the factory emissions manual since I knew it would be necessary living in CA. Fuel is definitely getting into the carburetor, but like you said either the mixture/idle setting is way off or something else internal to the carburetor is at fault.

 

[2mbb]

OK. two full turns out for the idle mixture screw is the starting point. From there you fine tune the mixture using the lead drop method (only requires a tachometer) or based on tail pipe emissions, intake vacuum, or something else. However, before you can do the fine tuning, the truck does need to idle with engine warm and choke disengaged. So you do have to solve that problem first. In my experience with my truck, the fine tuning adjusts the mixture screw farther out, making the mixture more rich.

I would recommend to remove the idle mixture screw to inspect it for damage, then screw it all the way in until it is lightly seated, then unscrew it 2 1/2 full turns...I would expect the truck to be able to idle. If not continue trouble shooting the other items.

 

[2mbb]

maybe at this point some pictures would help.

 

[socalsixty]

Thanks again for everyone’s help. Had a bit of time earlier to do some more troubleshooting, and found that the secondary jet was heavily damaged. Spent more time trying to remove it safely than anything else. The primary looks to be in good shape and neither looked clogged, but after seeing this I’m having my doubts about the quality of the rebuild.

Also, does anyone have any insight on which jet goes in which port? I assume the “primary” 1.47 jet goes in the left side of the bowl, and the “secondary” 2.00 jet goes in the right side? Looking from the front of the truck. Anyways, I have two new jets on order and will report back with what I find as soon as they arrive.

 

[2mbb]

Yes. That is correct. The secondary diaphragm connect to the secondary throttle plate on the frond side of the carb. That throttle plate is on your right when facing the carb from the front of the truck.

Where did you get new jets from?

 

[socalsixty]

Yes. That is correct. The secondary diaphragm connect to the secondary throttle plate on the frond side of the carb. That throttle plate is on your right when facing the carb from the front of the truck.

Where did you get new jets from?

Okay, got it. I sourced them from partsreloaded.com. They aren’t an exact match, but the only difference is the depth of the head and the primary jet being 1.475 instead of 1.47. I doubt the thousandth difference will change much.

 

[g-man]

Doubtful that a damaged secondary main jet would be causing your issues. Vacuum comes through the vacuum passage bolt at the bottom of the carb and works with the power valve. I think there is a small screw at the bottom of the power valve. Make sure it's there.

 

[socalsixty]

SOLVED! (kind of?)

Hey guys,

Thank you again for all of the tips and help with the issues I’ve been having with the truck. I recently purchased a used carburetor with about 150k miles to use as a troubleshooting tool. I installed the carburetor earlier today, and the truck immediately fired up, idled, and ran exactly as it should.

I’m not sure exactly what aspect of the “rebuilt” carburetor is to blame, but I will report back once I continue with that mess. I won’t bash the name of the company that “rebuilt” the carburetor just yet, until I see how they handle some sort of repair or refund (if I’m lucky).

Anyways, felt great to drive it around the block and let it warm up for the first time in a while. Pictures attached include the used carb installed, and the “rebuilt” unit on the tool cart.

 

[Dekeman]

Had my original carb rebuilt by my local shop in the fall, truck still ran like crap. Bought another "rebuilt" carb, ran a bit better, but still off.
Sent my original to Jim C back in Nov. while using the rebuilt, got the original back Monday (Jim's notes showed 8 things wrong with it) and installed.
RUNS LIKE A DREAM now. Always knew it could run like this after eliminating the cadre of other suspects. Finally.
Jim said if it a truck is still having problems after one of his rebuilds, it's not the carb.
Send your other to him, just be prepared for it to take a while.