Dudes!

Been a longtime lurker bummed my first post has to do with a problem on my truck. I own a 1983 4x4 Pickup SR5 with 160,000 miles and its in great shape with no rust or major problems.

But I was getting on the highway today and my engine totally cut out.

I checked the oil, it was very low on the dipstick. I know that I have to replace my main crankshaft seal because there is a leak but before I can get around to it I have been just checking and topping her off with a bit of oil (I drive the truck maybe once every 10 days and not far). The oil wasn't that low before I drove today but I didn't see a bunch of oil dumped out on the highway on ramp that I stalled out on.

Thinking the oil was the problem I ran to a gas station and bought some so I could at least get home. That didn't work, so I called the tow truck and got her towed to my garage.

Once i got my truck home I did some more inspecting and noticed that maybe I am missing a belt on the air pump? All the tech diagrams I look at in the FSM didn't really show that belt diagram, but upon searching and looking at other peoples engine bays it looks like that maybe broke when I was driving and the engine stopped?

The engine will turn over and it will start for a couple of seconds and I can keep it going by revving the gas pedal but if I take my foot off the gas she immediately dies.

I am a fairly good mechanic in the sense that I know how to use tools and can fix something if I have a guide or if someone points me in the right direction but I am pretty terrible at troubleshooting when it comes to car troubles. Any help is greatly appreciated. Glad to finally be an active member of this forum.

Cheers,
Zach!

 

What you are looking at in the picture is the air conditioning compressor.

Judging by the apparent lack of shine, or polish, on the compressor sheave, there has been no belt on that pulley for a long time.

The existance of, or lack of, an AC compressor belt likely has nothing to do with whatever caused your truck to quit.

 

Thanks, that was concise. My Ac doesn't work but came equipped with it. Can i remove that then? I dont use AC anyway.

The previous owner of the truck did tell me he removed smog equipment as well, but looking at the de-smog tutorial i dont see anything that resembles the removal of vacuum tubes or the entire emissions control unit.

If the truck fires, it runs for a second but stops is that an issue with timing or carburetion. Its getting a spark and its getting fuel if it starts, not enough air?

 

it may have the fuel cut solenoid on the carb. it would kill fuel to carb if it were malfunctioning. sounds like a fuel problem regardless.

 

Thanks msane99. I took out the solenoid and tested it based on the troubleshooting suggestions from weber:

"With the solenoid on the carburetor and ignition on and engine off,
disconnect the wire from the solenoid and listen for a click; then with the
engine idling, disconnect the wire leading to the solenoid. The engine should
stop. If the engine does not stop the solenoid is likely defective"

I did not hear a click when I tested it with the engine off and the engine wont run regardless.

This is what the solenoid looks like:



Does it seem like the solenoid is faulty and a replacement is necessary? Should I go ahead and rebuild the carb while I am at it?

Thanks again.

-Z

 

Do you have a Weber carb?


...I didn't think they had those solenoids.


I think you can test that thing by grounding the threaded part and applying 12V to the terminal end and removing it. That little part to the right should move, it's what causes the click you were listening for. I don't think the test you did would work unless you had the key in the run position, even if it wasn't actually running.

 

EnigmaT120 I do have a Weber 32/36 carb with electronic choke (installed by previous owner) in my truck. I tried seeing if the solenoid moved when it was out of the carb but didn't see anything, but this was when the keys were in the ignition in the on position but not fully turned to start.

 

That solenoid should be energised, and pulling back off the seat in the carb any time the ignition switch is set to 'run'.

Did you check for 12v on the solenoid wire when the ign switch is on??

 

Webers have them, it explains the 2 different idle jet physical sizes. the ones with a big one and little one originally had the provision for the fuel cut solenoid.


It would not have ran without it. you can just get the big jet seat screw and bypass that thing all together.


pull the jet from the end of it and make sure its not clogged. ground the base of solenoid and hit the blade with positive12 volt should feel or hear a click.


jets look burnt(shouldn't be a problem unless clogged though) rebuild might be good idea make sure you note what jet went where and the sizes they are. the one in tip of that solenoid will pull out, and in very tiny writing on side will tell you the size. there is another idle jet on other side of carb that also can be checked without tearing carb apart. it don't come into play till you are mid throttle..so might be how it is running sometimes.

 

also smog pump would be under your ac compressor, unless that is a idle pulley for ac, I can see it under AC in pict..

 

If properly tuned, you do not need that fuel cutoff solenoid. Typically they are needed on high volume performance applications where the carb is tuned more towards performance at a higher RPM range which would cause "Dieseling" during shutdown due to the rich mixture at idle. That's not to say that you can't use a fuel cutoff. I had a solenoid for my 32/36 that I was going to use just as a precautionary measure, but the design of the manual choke housing prohibits the use of a fuel cutoff solenoid so I went without and never had a problem. When I switch over to the 38 I still didn't use it and still no problems.

A well tuned carb/engine should should fire right up when warm and shut down immediately. Whenever I get a carb tuned and engine timed to where I want it, I always go back and test out how it starts and shuts down when warm. I make sure that it starts up with just a bump of the ignition (no gas at all) and immediately dies from idle when I turn the key off. If it doesn't do that then I know I still have some tweaking to do.

 

Msane99, thanks for the help! It definitely doesn't "click" or move when I do that.

Kawazx636 I looked up the term "dieseling" and my truck definitely was doing that before she stopped completely working and I noticed the last time I got it back from a tune-up that she smelled rich. I plan on rebuilding the carb and just buying a manual choke anyway (cause who can't pull a darn cable?). Also your build thread is freaking awesome and totally inspiring.