LUVTruck.com

Hey everyone!, I bought a 1980 4x4 stock as heck luv a few weeks ago, I am in California, so I have to keep this thing smog legal. This truck is from CA as well. I am not a mechanic but I am willing to tinker with the truck until I get this fixed. It runs pretty well, just has a rough idle. I have been trying to play with the carb to get it better but no luck. This carb is really clean, (Have not pulled it out) the guy I bought the truck from said it was recently rebuilt. So far I cannot find any vacuum leaks. I have been reading every post on this board about carbs that I can find. Seems like these stock carbs are lemons. But hopefully there is something that can be done! Something that I read was to check the anti-dieseling solenoid to see if it is functioning properly. With it removed the truck dies, but what I noticed is weather it has electricity or not does not effect the idle, is that normal? Also it sounds like there is supposed to be a spring in it, that does not seem to be there, could this alone cause a rough idle? I heard about the Weber carbs being good, but it seems like a lot to throw down for a carb that is not smog legal here. Any help would be much appreciated!!

Here are some pictures of the truck

Your vacuum lines maybe crossed I can't tell by your last pic. If you lines are wrong your eng will not idle right.
It would appear that you have a Calif smog truck if so here is a diagram to help. The two vacuum ports below the carb. on the battery side (right side of the eng.) the one on the left side go's to the Transducer, and the one on the right go's to your distributor.
Hope this helped.

sorry, dont have any information for you, but just wanted to say that is one sweeet looking truck!

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To the Oquirr hills for awesome thrills! Go-go 4wd, Activate!

Nice truck.

Your spark plug wires look really old in the pics. Check the resistance and get yourself a good set and it could be the problem. Get some new spark plugs, cap, rotor and points while your at it.

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Thank you!! I will try to go through all of the vacuum lines when I get home from work. That would make sense... That would be nice if that's all it is... does look like its time for cap, plugs, and wires too so I will try that as well. Anyone know how the anti-dieseling solenoid should work? And where to buy a new one? The replacement ones that I have found online do not look to be the same part.

The anti-dieseling solenoid is that hexagone looking thing with the red wire on it in picture #4. Should be 12volts on the wire when the key is on, 0volts with the key off. There is a plunger/needle on it that is pulled in when power is applied, with power removed the needle is pushed out by it's internal spring and blocks a port in the carb shutting off the gas flow to the idle circuit in the carb.
I suspect the carburator may just need adjusting properly.
Make sure there are no vacuum leaks and every vacuum line is in it's proper place. Start by warming up the engine to normal operating temperature, then shut it off. Turn in the carb mixture screw (right one in picture #4) and lightly seat it. Then turn it 3 turns to the left as a starting point. Start the engine and note the speed and set it to 900 rpm with the idle speed screw (the left one in the picture), then go back and slowly turn the mixture in or out a half turn at a time to find the fastest, smoothest idle place by also keeping idle speed at 900 rpm. Go back and forth between these two screws as needed. When this best point is found slowly turn the mixture screw (right one) in about 1/4 turn so the speed drops just slightly to 850 and you are done, and the truck will meet emissions too.
Sorry for the long post but I could do it in a minute but it is hard to explain. Hope this helps.

Okay so I checked the vacuum lines, they all seem to be in order. Does anyone know if the transducer is supposed to have a open hole on the bottom? I noticed there is a nipple on the bottom of it that looks like there should be a pretty thick hose hooked up, but I cannot find anything that would go there? It sucks air from that hole pretty good, but seems like that might be what it is supposed to do. Also from what was posted earlier it sounds like the anti-dieseling solenoid would need the spring in order to work correctly, does anyone know where I can order a new one? The ones that I have seen online do not look right...

Last night I noticed that if I plug the fat hole inside the air filter (Looks like it goes to the smog pump) and the truck runs way better, is that a bad thing? I assume come smog time in two years I will have to unplug it provided there are not added consequences from doing so...

Yes the transducer hole at the bottom connects to a metal tube with a rubber sleave on the transducer end. The tube should go to the EGR crossover/EGR valve area at the bottom of the intake manifold. Looking down at the transducer kinda underneath it and down and to the left. This tube samples exhaust pressure at this point.
From what I can see in the picture it looks like your smog air pump is kind of non-stock and hosed up. On my 79 the diverter valve was mounted on the pump itself, not over on the right side above the distributor with hoses running across the engine, etc. Of course mine was a 79 and not an 80, maybe that was changed I don't know. Maybe someone on here knows for sure. It almost looks like someone had to scrounge up a system maybe from a Toyota or something and tried to adapt it to the Luv. Anyway the attachment diagram above from woodmanhc shows how the transducer valve is connected. More help I hope.

egg, that was a beautiful explanation of carburetor adjustment.
So, I'm going to mark this so the search will find it easier.

Stock Carburetor Adjustment
Carb Adjustment
Setting the carb
adjusting the idle
adjusting the mixture

Anything else that somebody could search for when they're looking for this?

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1980 4X4 LUV daily driver, as stock as can be.

From what I can tell from compairing to the Haynes manual I have all of the smog equipment looks stock.. The smog pump matches the oe on rockauto.com... hmmm... question about the transducer, just so I am not mistaken the transducer mentioned above is a plastic canister near the battery?




My truck has a vacuum routing diagram under the hood that looks pretty different from the one posted on here. Must be a difference with a 1980 California 4x4.

The transducer is in picture #5 off the corner of the battery in the photo but mounted on the intake manifold. Looks to have some white letters scrawled on the top. The plastic canister in your latest photo is the fuel tank vapor canistor.
Yes you are correct, some things have been changed and added since 79 model, and it looks like you do have a California model which is probably the major difference. More complicated I'm sure.