Rebuilt Carb - First start attempt is a no-go (1 Viewer)

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Ok- I got it to start... kinda... It's sputtering and I have to keep pumping the gas pedal. When I stop it dies. But definitely not even close to an idle.
 
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Ok- I got it to start... kinda... It's sputtering and I have to keep pumping the gas pedal. When I stop it dies. But definitely not even close to an idle.
What are your settings at on the carb? IM, (idle mix, in back closer to valve cover) and the other... haha, I can’t even recall now, the one closer to the facing right side base area. The third thats further out to the facing right is for your fast idle w/ choke pulled, should be set at about 1,800.
 
What are your settings at on the carb? IM, (idle mix, in back closer to valve cover) and the other... haha, I can’t even recall now, the one closer to the facing right side base area. The third thats further out to the facing right is for your fast idle w/ choke pulled, should be set at about 1,800.

I'm not sure how to go about adjusting anything on the carb. I just had it rebuilt.
 
I just tried adjusting the 3 different screws and nothing is changing. All I'm getting is a very weak sputter that dies immediately.
 
IM on the back should be screwed in fully but not crazy right. Then back it out 2-3 turns. On mine I had colored half the head of the screw so I could have a better visual for counting. Idle Speed, inner base, similar, screw it in fully but not crazy tight then back it out a couple turns. Fast Idle out to the far side, would be adjusted w/ choke pulled as I said before to 1,800.
Are you trying to do all this w/ the air cleaner cover on or off? Make one of these so you can adjust the carb w/ the cover on. And have a pen light handy too.

726DE0CA-CF75-456A-8360-5316C6A73C1E.jpeg
 
ICS connected and working properly? Can you hear it clicking with key on and off?

This is interesting. I did some light reading and my symptoms seem aligned with a bad ICS. It is connected, but not sure if it's functioning.

What is the clicking I should be listening for? And if I am seeing fuel enter the carb, when pressing the gas, is that as all related?
 
Clicking is just that. A click when the Solenoid is opening. What you can do to see if its working is with the engine off turn the key on in the cab then plug and unplug the connector where the ICS connects. You should hear a 'click' sound as you plug and unplug the connector if its working properly. The o-ring on the end of the plunger sometimes can get sticky or disintegrate and cause the solenoid to stick not allowing it to open. The solenoid is ground switched I believe and grounded at the emissions computer and the grounds there can go bad over time not allowing the Solenoid to operate. I am not sure thats your issue here but you may just want to just make sure that its working properly to rule it out as a potential cause. If you hear a click, then you are prolly good. If not then would want to find out if its electrical or something else. You can bypass the EC and ground the ICS directly to rule out the EC grounds as a cause.

Having said all that its prolly more to do with carb tuning. Since the carb was recently rebuilt it would make sense to focus on that. Maybe check out OTRAMMs videos on tuning the carb on a 2F. Some of the same stuff @NeverGiveUpYota was mentioning previous:

(4) Toyota 2F Aisan Carb Idle Mixture Adjustment - YouTube

There are prolly numerous ways to do this but I thought this video was a good starting point. HTH.
 
bring a temporary constant 12V from the battery to the ICS and ground the other terminal, then try to start. When you connect up the ICS to the battery you should hear it click or not. If no click then maybe the ICS is bad. If it does click and it still won't run, I would check the distributor again (are you sure you were at TDC on the compression stroke when you installed the distributor). IF the ICS clicks and the engine runs with it jumpered but not with it connected, then you have a problem with the ICS circuit. Good luck.
 
Just checked the ICS and it is clicking when connecting the plug. I will next dive into tuning the carb in hopes that is the problem.

I have my power steering gearbox off, but hoping to have that back on in the next day or two, and then will proceed to the carb.
 
Just checked the ICS and it is clicking when connecting the plug.
IF the ICS clicks and the engine runs with it jumpered but not with it connected, then you have a problem with the ICS circuit.

You may still want to try @2mbb's suggestion. That's prolly a better overall test. You could have an issue with your EC not causing this to run properly even if it clicks. I had issues with the solder joints on my EC, and every test I ran got the ICS to click. I hard grounded the ICS to the carb for a bit and issue went away for me so I knew I had a grounding issue that wouldn't show up when I did the click test. I reflowed the solder joints on the EC board and problem is gone for me. The test @2mbb is easy enough to try. There is a lot of stuff that can go wrong to cause the Idle cut circuit to not work properly as to be something other than just electrical. I think there is also a vacuum switch in there as well that tells the EC when to electrically open/close the ICS. This test would rule all that out and if it still doesn't work then you can move on. But if it does you can then see where the issue is with the IC circuit. Not trying to tie you up in senseless tests but trying to be thorough.
 
Forgive me, I am very novice (read dumb) when it comes to electrical work. As in, I don't know how to "create a temporary constant 12V from the battery". How do I know which wire on the ICS is power vs ground?

The ICS is clicking when I connect the plug to it. Is the idea that it could have enough power and ground through the wiring to make it click, but not function properly?

I reviewed the Otramm video, but I can't even get it to start in order to tune it. I tried matching his starting point, and then working it out testing various phases.
I tried putting the air filter on and attached all associated vacuum hoses. This video shows my best yet. Heavy sputter, extremely rough and low idle - maybe 200rpms (I don't have a digital tach). It also sounds like there is a loud exhaust leak, but full exhaust is hooked up so not sure if it's from the rough idle/sputter or not yet. Sounds like a misfire, or as if its not firing on all 6.
Distributor was definitely installed at TDC on the compression stroke. Could it even be possible to adjust the valves on the right stroke? I couldn't even I did that, but it was so long ago I can't say for sure, but would the adjustment range even allow for that? And would that cause this?
 
Just finished rebuilding my head, and the carb.

Forgive me, I am very novice (read dumb) when it comes to electrical work. As in, I don't know how to "create a temporary constant 12V from the battery". How do I know which wire on the ICS is power vs ground?

The ICS is clicking when I connect the plug to it. Is the idea that it could have enough power and ground through the wiring to make it click, but not function properly?

If you look at the ICS plugs, there should be two colored wires coming off the ICS side of the ICS wiring. If memory serves the wire colors are different between the ICS plug and the vehicle harness side. On the ICS side plug you should see a white wire with a black stripe and a black wire. The white wire with the black stripe is ground and the black wire is hot. So if doing @2mbb's test, you would just unplug the ICS plug, create some jumper wires from the battery to the ICS side plug. + from battery to the black wire on the plug and - to the white/black wire on the plug. Then connect the jumpers from the battery to the terminals in the ICS plug (plug closest to the ICS itself). Hopefully that makes sense.

What this system does is prevent unburned fuel from entering the exhaust during decel by temporarily cutting off fuel flow. It also allows the engine to not diesel after shutoff. As mentioned its controlled by the Emissions computer which is basically a PCB. The ICS is ground switched through the EC based on input from an electrical vacuum switch. So doing this test @2mbb suggests effectively bypasses all that to force open the ICS. Your video sounds like what you hear when you unplug a working ICS with engine idling. But it could also be caused by other things so you really just want to rule out the ICS as being this issue and move on to the other things. I had an issue with my ICS where I could get it to click with engine off but still caused issues during engine idle. So just bypassing all that stuff to see if you can get the engine to run with it bypassed. If engine does run with the bypass in place, then you know the ICS system is your issue and can figure out whats wrong with it. If it still doesn't run then you can move on to other things.

Here is a good video of showing the ICS system actually working:



Diagram of the setup:

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Have you hooked up a vacuum gauge to the truck? What sort of vacuum readings would you see when the engine is idling rough? Was the carb rebuilt by one of the carb gurus on mud? Since the head was rebuilt, I assume you replaced all the intake/exhaust gaskets with Toyota OEM ones? Any leaks there? Just rule out the ICS bit and move on to basics. Double check the firing order, check for spark as suggested (I didn't see where this was done yet), Dizzy position, initial timing, etc. HTH.
 
I mentioned the distributor installation because I come across folks that don't understand the difference between TDC and TDC compression (I'm not saying this is you, though). The four-stroke engine has the piston at TDC at two times, once on the compressions stroke and once on the exhaust stroke. Just because the timing pointer is aligned with the TDC mark on the flywheel doesn't mean the the engine is at TDC compression. You need to confirm you are on the compression stroke either by checking the position of the valves, confirming the piston is pushing air out the spark plug hole, or some other means (since the distributor was removed you can't go by the position of the rotor). At TDC compression both the exhaust and intake valves for the cylinder should be closed and, if adjusted properly, the rockers will be somewhat loose. Or, with the spark plug removed, and while turning the engine to achieve TDC, you can put your thumb over the spark plug hole and should feel air pushing past your thumb. If you did this, great. The other think I would check is to make sure your spark plug wires are connected properly for the 2F firing order: 1 5 3 6 2 4

I'm not sure about your question on the valve adjustment. If you didn't adjust the valves correctly, I suppose you could have similar symptoms. Below is a link to a post about valve adjustment...you do have to find TDC compression vs. TDC exhaust. Use either the hot or cold gap numbers, it shouldn't make a difference just to get it started. Either way, you should check again once the truck is running and the engine is hot/warm. Remember to have fun!

 
Thank you both for the in depth information.

I ran a constant 12V to the ICS and it's clicking just as it does when plugging it in and nothing has changed.

On the distributer, I definitely set it at TDC when air was pushing out of the #1 spark plug hole. Would it matter which way I was turning the crank? If I set the valves on the wrong stoke, couldn't that be an issue?

Should I go after the valves next?
 
OK. It sounds like you were TDC compression when you installed the distributor. If you are not convinced that you set the valves correctly, then go back and check them again. You can use the table I linked earlier. At this point it's not so much getting the valves exactly perfect, but making sure they are open and closed when needed. When a valve is closed you should be able to fit the feeler gauge between the rocker and the valve stem. When it is open, the feeler gauge won't fit.
 
OK. It sounds like you were TDC compression when you installed the distributor. If you are not convinced that you set the valves correctly, then go back and check them again. You can use the table I linked earlier. At this point it's not so much getting the valves exactly perfect, but making sure they are open and closed when needed. When a valve is closed you should be able to fit the feeler gauge between the rocker and the valve stem. When it is open, the feeler gauge won't fit.

We confirmed TDC on the compression stroke. Dizzy was correct, as were all the valve adjustments according to your guide.

I'm at a total loss now.

Is there anything else on the carb I can check out. I had pulled the EGR system and reinstalled it. Is there anything I should be looking at there?
 
Fuel just isn’t getting all the way to the carb? Or
I can't even get it to start in order to tune it.
Have you checked your engine fuse? I had some no starts once and that’s what it was...

ignore all that. I listened to the video. Why is the battery light fired up?
Choke is pulled?

IM is open at least 3 turns? Idle speed screw is at least turned 3-4 so it’s pressing the metal below it?
 
Fuel just isn’t getting all the way to the carb? Or

Have you checked your engine fuse? I had some no starts once and that’s what it was...

ignore all that. I listened to the video. Why is the battery light fired up?
Choke is pulled?

IM is open at least 3 turns? Idle speed screw is at least turned 3-4 so it’s pressing the metal below it?

I pulled the #1 spark plug out and it smelled of fuel which leads me to believe it's no longer a fuel issue?

Choke is pulled, that's the only way to make it barely sputter start. Doesn't even do that without the choke pulled.

I'm not sure about the charge light. The battery was out of the car for 8 months and I've had a tender on it charging. Figured that's what is was but tender is now green and I still have the charge light.

Please remind me which adjustment the IM is? Idle speed screw is the brass one on the valve cover side correct? What is meant by "so it's pressing on the metal below it". How can I gauge that?

Not even aware of what an engine fuse is
 
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I pulled the #1 spark plug out and it smelled of fuel which leads me to believe it's no longer a fuel issue?

Choke is pulled, that's the only way to make it barely sputter start. Doesn't even do that without the choke pulled.

I'm not sure about the charge light. The battery was out of the car for 8 months and I've had a tender on it charging. Figured that's what is was but tender is now green and I still have the charge light.

Please remind me which adjustment the IM is? Idle speed screw is the brass one on the valve cover side correct? What is meant by "so it's pressing on the metal below it". How can I gauge that?

Not even aware of what an engine fuse is
Oy. IM is on the back side closer to valve cover. Idle speed is closer to the right side tucked in at the base of the carb. The screw seats down on a metal linkage. You can see the linkage move as you tighten the screw in.
 

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