Advice needed. (1 Viewer)

[cruiserboy14]

I know many of you have more experience than I so I ask, should I break down and get fuel injection or stick with a carburetor?

Here’s my info and conundrum. I have a 77 us spec fj40. I have had the carb professionally rebuilt (don’t remember who) and without to much use, it is not running right. I have rebuilt a new carburetor but don’t know how to tune it properly. I was never taught and I don’t know a good manual. I’ve looked on YouTube but I’ve only found one and he uses the rpm to gauge it. I don’t know how to check my rpm.
On another note I know the carb is running rich (I can smell it bad! And it’s dieseling). I’ve tried the mixture screw but no real luck.

Sorry for the rant, but I’m getting frustrated with my lack of knowledge and stagnation. I just feel like I’m wasting money on the carb at this point that I could put towards a fuel injection system.

Thanks for any help everyone.

 

[B y r o n]

I would suggest finding a good local mechanic. He/she should be able to straighten out your carburetor issues.

It sounds like you may be weak in the mechanical arena so you would need a good mechanic to install your EFI if you decide to spend the money and go that way.

There are benefits to EFI over standard carburetor setups, it is just a matter of if you want to move away from OEM or update to a more modern EFI setup.

 

[cruiserboy14]

@B y r o n thank you. that’s another avenue I’ve thought. I’m just not sure of a decent one that deals with carburetors. Many don’t mess with them. I like to think I’m mechanical minded, but even though I’ve rebuilt on, carburetors still mystify me.

 

[Skreddy]

It could be more than just the carb. Diesel I g could come from throttle blades too far open (which may explain why the mixture screw has no impact), or could be timing related, or it could be float level too high. If it’s points, could be weak points, dwell more set correctly, etc. then there’s potential vacuum leaks, valve adjustment, condition of wires, cap, rotor, fuel filter/lines/tank….
I’d imagine someone is local that could help? I’d start with seeing what the timing and vacuum is, and go from there. The members on this forum can walk you through anything. EFI is great, I just did it. But it would really suck to go through all that and still have the same issue because it was ignition related, etc

 

[h82crash]

Carbs are a simple machine. Air is pulled through the venturi (narrow part of the throat), which creates a vacuum that sucks fuel out of the bowl through metered jets. If they're already properly jetted, the calculations for the mixture is done for you. The only real adjustments are idle speed and idle mixture. But you need to make sure everything else is correct. Timing, valve lash, clean points if you are still running them. You need to identify the adjustments on your particular carburetor, the location of the idle speed and mixture screws. IE, are you sure you're turning the mixture screw? And your engine must be at operating temperature.

Since the adjustments are idle speed and mixture, it only affects idle. But idle affects transition. The following are common symptoms.

If your idle is rich, it will burble, idle rough, sometimes stall after awhile. The transition to higher rpm will struggle until you burn the excess fuel out.

If your idle is lean, it will miss, run rough, stall. If it does keep running at idle, the transition will cut out when you open the throttle. Slowly pushing the pedal helps but you may have to pump the pedal, which adds extra fuel from the accelerator pump, to keep it running. These are extreme examples so the symptoms may be more subtle.

So, adjusting idle is balancing the fuel (idle mixture) with the air (idle speed).

Yes, you should have a tachometer, an old diagnostic instrument you attach to the coil. Experienced folks can do it by ear. Many timing lights have a tach built in. You need a timing light to ensure your timing is correct before messing with the carb. Can you borrow a timing light? Rent one?

I hope these tips and info help you understand what is going on and the procedures in the FSM or in threads on here will start to make sense.

 

[Mean One]

I also have a 77 and live in Tucson. I do most of the maintenance on my 40 and know how to tune a carb (self taught) and have the equipment required. I’d be happy to help. PM if interested.

 

[TheHardWay]

Dude, if I was you I'd jump at that offer.

 

[Catching Neutral]

Times 2, If you stick with the carb you absolutely should learn how to do a valve adjustment, tune the carb, and set the timing. All three are key to a happy 2F

 

[cruiserboy14]

@Mean One pm sent

 

[fyton2v]

Info and advice on Mud are very, very helpful. However, people often take their knowledge for granted. Also, the factory service manual is incredibly helpful, but it also leaves out A LOT of contextual info. It presumes knowledge that's needed to fill in gaps. Another thing you need to consider is that tools are often taken for granted. A timing gun, vacuum gauge, and a gauge that can display RPMs are essential tools, and pretty cheap to acquire. But the rest of the toolbox can get pricey. Most of us have been amassing stuff over many years and we have all the foundational things needed to dig into a motor. That said, perhaps the biggest factor to consider is your time and motivation. If you have, or are willing to get all the right tools, all you need is motivation. Anyone can learn how to work on these motors. Anyone. But if you generally prefer to pay someone to change the oil in your vehicles, finding a good, independent mechanic is probably the way to go. You'll really want someone that has worked on older Land Cruisers. This person will exist in Tucson.

 

[h82crash]

Info and advice on Mud are very, very helpful. However, people often take their knowledge for granted. Also, the factory service manual is incredibly helpful, but it also leaves out A LOT of contextual info. It presumes knowledge that's needed to fill in gaps. Another thing you need to consider is that tools are often taken for granted. A timing gun, vacuum gauge, and a gauge that can display RPMs are essential tools, and pretty cheap to acquire. But the rest of the toolbox can get pricey. Most of us have been amassing stuff over many years and we have all the foundational things needed to dig into a motor. That said, perhaps the biggest factor to consider is your time and motivation. If you have, or are willing to get all the right tools, all you need is motivation. Anyone can learn how to work on these motors. Anyone. But if you generally prefer to pay someone to change the oil in your vehicles, finding a good, independent mechanic is probably the way to go. You'll really want someone that has worked on older Land Cruisers. This person will exist in Tucson.

I'll add 2 more cents. If you own one of these machines or any BMW, you need to learn how to maintain it. If you don't, be prepared to drop tons of money paying someone else to do it.

 

[cruiserboy14]

I’m not afraid to maintain my 40. I find it enjoyable even! I’ve fixed and adjusted many parts. It’s a part of owning a 40 and being able to be self sufficient that I love. There are certain procedures and part that i feel are over my head at the moment, sadly. I’m not a fan of taking my cruiser in to the shop for work. I have! I won’t lie. But my goal is to do it all myself.

 

[dmaddox]

Add to the fact that if you can...

1. Lean/drop and adjust a carb.
2. Set the timing/"dial in" your engine.
3. Adjust the valves.

You'll feel the urge to chop wood, whittle a canoe out of a pine tree and toss a stetson on like Sam Elliott.

 

[SteveH]

With apologies to Heinlein....​

“A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, rebuild a Land Cruiser carburetor, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.” ​

― Robert A. Heinlein

 

[Pighead]

I’m not afraid to maintain my 40. I find it enjoyable even! I’ve fixed and adjusted many parts. It’s a part of owning a 40 and being able to be self sufficient that I love. There are certain procedures and part that i feel are over my head at the moment, sadly. I’m not a fan of taking my cruiser in to the shop for work. I have! I won’t lie. But my goal is to do it all myself.

Good. This is 'Mud, not Angies list. We are much better at telling you how to do something than telling you where to have it done.
You say you have an old professionally rebuilt carb, and have rebuilt a new carb. Which carb is on it now?
Tuning a carb starts with tuning the engine. You must learn/know how to adjust your valves pretty
well. You must know which directions to rotate your dizzy to advance and retard timing.
While rebuilding a carb, you should have learned the names and functions of the screws. If not, review your work.
How does one rebuild a carb without a manual?
Everybody here has tackled a procedure that, at one time, seemed over their head. But with the help of 'Mud, an FSM, and a toolbox, we pulled it off.
Show us pictures of your carb, your dizzy and your toolbox.