I'm starting to notice the small issues now that I have the truck together. One problem I can't seem to correct is the idle. When the truck is cold it idles very high. When the choke releases after warm up it drops a few rpm. Then when it gets hot(normal temp) it idles very low. I have the carb's choke, air, and fine air/fuel settings tuned for the best of both worlds so when it is up to temp I can turn the a/c on without the engine stalling. This doesn't seem to be the way it is supposed to run though. I have checked the flap for winter running and it is closed to the exhaust feed, meaning it is set for summer, but there is no vacuum through the hose on the little motor that operates it anyway(I need to check this). I need some pointers. Either this is how these trucks run, or I need to look at something else. The air cleaner is good. The engine runs smooth, but has a slight tremble at low rpm's. I have not checked the timing or messed with the distributor. There are no vacuum leaks (checked with a vacuum tester as well as a can of WD-40 around all the hoses). The plugs and wires are good. There are no leaks in the intake manifold. What else am I missing? How do you tune these engines to run the smoothest and how does the choke/carb work together normally, meaning is it normal to change rpm that drastically from cold to hot? Any other pointers? Thanks, cdover73
Okay here's my update. With engine cold I pulled the valve cover to check valve adjustmen. Everything was spot-on per factory specs. Replaced valve cover and moved to carb. Per fupabox's youtube video on carb adjustment (thanks fupabox!) I started with the high idle adjustment. Cranked the truck and made a few turns in both directions...no change in idle. I put it back where it was and moved to the air/fuel setting since the engine was now warm. There was plenty of instant response from this adjustment, but it I still couldn't find a sweet spot. I put it back where it was and started looking at the choke adjustment. I noticed the set screw was run all the way in. I screwed it out a little and the idle started dropping. I compensated for this by adjusting the air/fuel. However, if I backed the choke screw out more than 1 turn it would die. I checked the pre-wound spring around the choke shaft and it seemd very loose. After getting no where with this, I moved to the timing. The first thing I noticed was the distributor was maxed out at the counterclockwise end of the adjustment slot. The timing mark on the front was about 2 inches from the pointer, and the flywheel marks wasn't visible. I tried to keep it running while adjusting the timing and the crank marks would come closer to alignment but still no visible marks on the flywheel. After all this I basically ended up right back where I started. The engine cranks with a bump of the key and doesn't run hot, but sometimes will stumble a couple of revolutions when I kill it. This tells me the timing may not be right. It runs good like it is but stil idles lower and lower the hotter it gets to the point of stalling when I come to a stop or turn on the a/c. I can keep it running by feathering the throttle. I have searched and read all the posts I could find on this issue with no final resolution. Can someone please give me some pointers? Thanks, cdover73
If I remember right your dist. has just 2 cogs rather than a fine toothed gear. If this is the case you may need to check the timing belt to see if it's off a tooth,that's what it sounds like to me. You really need to get that figured before you can adjust the carb. I've found that if you hook up a vacuum gauge when your adjusting the air/fuel and set it where the vac. is highest it works pretty well.
I did change the water pump which required removing the timing belt. I called myself being extra careful. Didnt move the gears, marked the belt and gears before pulling it, and put it right back the way I took it off. This doesnt mean it couldn't be a tooth off, but it did line back up with the marks I made. I will double check it. I have had belts slip a tooth before and the engine ran very erratic and wouldn't stay running at all. This one starts right up and purrs smooth as long as rpms are above 1000. Definitely got me scratching my head.
Okay im about ready to sale this darn thing!!! Now im having issues at the other end when it gets hot. The more I run it the more it wants to rev erratically and die. I cant understand why after it gets hot the auto choke wants to over rev the engine every time I step on the gas pedal. I can just touch the pedal and it literally runs away while the choke settles back in. Why does it do this? I thought once it got to temp the auto choke worked less, not more??!!! I checked the timing belt and it is fine. I still cant adjust the timing from max advance without it dying. I have played with the carb choke setting (the small screw to the rear of the carb that works the geared linkage). I screwed the cold idle setting all the way out with no change in the revving. It runs fine when cold but higher idle than I would like. But when it gets hotter it makes me want to set a match to it! Can ANYBODY please pitch in with some advice? Is Leon still around? Somebody has to have an idea.
Try to pm fupabox,him and Trax&Horns, Terry,are pretty much the Hijet guys.I appreciate your frustration but don't have a clue. As far as I know Leon is still around for at least another year but only one day a week,either Tues. or Wed.
Two questions... 1. Ive read elsewhere on here about the black box behind the glove compartment maybe having something to do with the idle and such. I thought it was the computer, or brain box. What is it exactly? I havent tried unplugging it to see if it would run without it. 2. As I said, the hotter the engine gets, which it never exceeds half way on the guage so I assume its normal temp, the more the choke seems to govern any throttle input. I can lightly step on the gas and it revs away and slowly returns to idle. There doesnt seem to be an adjustment for this. What controls the choke to make it do this? Is it one of the solenoids on the carb, vacuum, the wax thingamajig??? Im at the point of considering a new carb, but this has to be something simple. Anybody??? Thanks, Cdover73
Have you seen the thread TRAX&HORNS has in the Honda Acty section? That's more than likely the kind of thing you're going to find with your truck,something really simple but hard to find,that will have you cussing when you locate it.If you decide to do something with the carb. Terry has had good luck with an outfit in Ohio called Hite rebuilders or something like that.They run a little over $300 or Don at Yokohama Motors will sell you a new one for about the same price.I hate to see you spend your money with out being sure that's the problem.
Been there brother a number of times with theses carbs. The number one thing is checking for vacuum leaks. But if the carb was sitting around for a few months + There could be some varnish buil up, floats hanging up ect. Most of the time a good couple doses of sea foam will clean it up. But sometimes you have to bite the bullet and send to Hite Parts and let them Do their voodo. The best thing about them is that they do a 100 % tear down, cleaning then they do a flow test and preset Everything. Basically a brand new carb. It appears that you have done everything so far. Hite Parts folks are as good as they come and I highly recommend them. They will keep you from pulling your eye lids out.
So are you thinking it may all be in the carb? Im leaning that way but im still trying to figure out the automatic choke and what makes it work. Can I disconnect it and see how it runs or will that cause other problems? Im in south Louisiana so cold weather is definitely not an issue.
On my S80 the choke was dis connected by the previous owner and it works fine. There is no high idle warm up but, like you,I'm in a warm climate so it doesn't matter.I've always believed that automatic chokes have the potential to cause a lot of grief especially if,like us, you don't need them.
Alright, so with nothing to lose I pulled and tore down my carb today. It was filthy. I went through it completely, had to make a couple gaskets and change an oring, and preset the adjustments to where I thought was a good starting point. I also gave it a good bath in carb cleaner and seafoam. Also added seafoam to fresh gas in the tank. I reinstalled it and fired it up. It runs a lot better but still a little erratic. I didnt feel like messing with it more tonight. The one thing it isnt doing is running away with the choke any more after it gets to temp. Im glad to see that! I still cant get any response from the cold idle adjustment no matter which way or how much I turn it. The air/fuel is responding better though. I will fool with it more this week to see if I can smooth it out. There is one thing that keeps happening that is puzzling. For some reason the coil wire is being blown from the distributor. I snap it in tight and all of a sudden when I turn the engine off I hear a spark and the coil wire is hanging loose. It doesnt do it all the time, maybe 4 or 5 times since ive had the truck. Ive never seen or heard of this before. Anybody else?
I tinkered with it more today. Tried a combo of things and in the end its running better than it ever has, but still not right. I pulled a vacuum test at various points. Didnt think it would matter where I connected but apparently it does because I got different readings at different points. One was obvious, the hose from the carb to the advance on the dist. There is a pin hole in the carb fitting that restricts the amount of vacuum there. Im not sure if its working properly inside the advance but there was a steady .5" vacuum. The other readings were in the normal range from 18-22". I was also able to adjust timing without it dying as it would before. I set it to ear and adjusted the carb from there. I know im gonna hear again that I have to get the timing right before the carb, but at least im back to a solid starting point. I can put the timing light on it now to fine tune. It still has a dead miss, or cough, while its at the lower rpm range. With the coil wire blowing off im gonna get a new set of plugs and wires. The cap and rotor is new. Im also gonna start replacing all the vac lines just to eliminate any oversight. They hold steady vacuum and dont respond to the wd40 test but all it takes is a pin hole sometimes. Nobody ever answered the question about the black box behind the glove box. Is that the main computer? I have a right hand foreign truck but the speedo cable was cut off at the tranny and that box was unplugged when I first got it. Speed limiter by chance? If so could that be some of my problem? Thanks,
I don't know anything about the black box but the speedometer box at the tranny sounds like an S80 or 81 that was governed that way for U.S. import.Does your carb have 2 solenoids? If so one of them is connected to that box at the tranny and designed to close at 25 mph.My S80 is set up this way and to get around it the p.o. just ran the cable direct to the tranny and zip tied the box up out of the way.If you have the solenoids they have a tiny O-ring on the end of the plunger that can make it run rough. Sounds like you're closing in on it,I know how frustrating it can be, especially when you have a mixture of components like you're dealing with, but they sure are a kick once you get it going .
According to the tag under the seat its a 93 S83P with the ef-cs engine. The black box is behind the glove compartment and has a multi plug wiring harness plugged to it. On most normal vehicles this would be the PCM. The speedo cable or tranny doesnt have a box. They just cut the end off the cable where it screws into the tranny for some reason. Could be unrelated to a speed sensor. The carb has two places where wires attach. One is a plunger type solenoid with two wires at the rear of the carb. The other shares the same plug in but only has one wire. This one is at the right side of the truck just in front of where the air box hose connects. I found the drawing and parts identification on here so I will have to look at it again to give the proper names of these. Btw, it doesnt change how the truck runs with these wires unplugged. That may be a problem in itself.
On the S80/81 one of the solenoids is the speed limiter and the other is a fuel shut off that closes when the key is turned off to prevent dieseling. I think that all of them have the fuel shut off one. On my truck I lost the O ring on the end of this one and it really ran poorly.As far as I know if this solenoid doesn't have power when the key is on it shuts the fuel off.I'll try to attach a pic of the S80 carb on the EB engine.OK the site won't let me upload for some reason,sorry.
I pulled the dist cap and found the coil receptacle to have a lot of crud in it. Cleaned it up and put everything back together. The truck ran for a while then acted like it was not getting fuel and died. I removed the new fuel filter and connected the line straight without filter. The truck cranked right up and ran great. I took it for a few laps around my field with no problems. I let it idle while I went inside for a few minutes but when I got back in to take off it started dying again. After fumbling with the coil wire to no success I pulled the fuel line to see if I had gas to the carb. Nothing. I put the fuel line in a plastic bottle and turned the engine over. Nothing. Now I have the mechanical fuel pump off and trying to figure out how to check to see if its bad. It looks like the plunger rod has beat a good indent into the pump arm so im wondering if its just not getting a full stroke. Either way, im gonna get an in-line low pressure electric fuel pump and plug off the mechanical to see if that solves it. If it does I guess I will spring the $150 for a new pump, just because I want to keep it as stock as possible. I am still having an issue with the carb. When it gets hot the spring on the choke setting with the plastic gear gets a lot of slop in it. Even adjusted all the way in it wont hold the choke completely shut for starting. I may say the heck with it and get a new carb that has tighter tolerances.
Okay...fingers crossed. I think I finally have it all fixed!!! Installed an electric fuel pump and all the stalling issues have gone away as well as some of the carb issues. I guess the weak/failed mechanical fuel pump was causing the carb to have to suck in what gas it was getting, basically assisting the pump on its last leg. I just completed more driving than I have done yet, it fires right up, idles smooth and at the proper rpm's, and has plenty of power. It's been a long haul, and reading back through this post makes me shake my head. I guess it was more of a diary than anything, but hopefully my path to success will help others in the future. Now I'm not counting my chickens, this thing could not crank tomorrow. But for now I am happy!!! Thanks to everyone that pitched in also! now where did I put that for sale sign.... cdover73
Congratulations !! As so often happens it's something pretty simple but a real pain to find. You sure paid your dues so enjoy it before digging out that sign.
Yeah it's been a long one. I have had the truck about two months and have touched literally EVERYTHING on it. There is absolutely nothing I did not touch. The problem is, I don't feel like I know the truck any better now. I'm sure I do, but it doesn't feel like it. I hope to take it to our camp for the 4th and see how it does. Maybe even put it through a little mud, just to "test" it.... Hopefully it does good. The only two things I know I still have problems with is the 4wd button not activating the front axle in high and the a/c stopped blowing cold but the compressor is running. I think I may have ruined the compressor. Put 134a in it without converting it. And I'm not sure it took an adequate amount of oil when I pulled vacuum. But the windows do roll down! And, they clear the door speakers!!!
Arghhh!!! It started doing the same thing again today! Didnt make it out of my driveway and it went dead. Got it back to the shop and checked the fuel. Wasnt getting any with the new fuel pump. Then it dawned on me...pull the tank. Yep...about 2 inches of rust and crud in the bottom! Drained it, threw a few rocks in it from the driveway, called my daughter out to help and we shook it good. Got it as clean as I could and put it back. Then blew out all the lines with air and seafoam and pulled the carb for good measure. With the filter at the pump and a new inline filter there was still gunk in the main jet. I also checked the fuel shut off switch with 12 volts and it wasnt clicking. I happened to push the plunger inside the end and it suddenly popped like it was stuck and came free. Checked again with 12v and it was music to my ears...click, click, click! With a couple minor setbacks today I am rolling again. I expect a couple more bouts with the fuel but at least I know where to look. And I have gotten so good at pulling the carb that I dont even need pics to remember where everything goes. The coil wire is still blowing off the dist cap though. Very weird...
