I have a '91 S83p, which I love. I bought it in Chicago from a couple of hillbillies who didnt treat it very well. Dont know how many miles are on it, the odo doesnt work, I think they tried to force it back and broke the 1000s digits. I've had it 5 years and it ran pretty well until a couple of months ago. I have a Danko manual. At first it started performing like it was only running on 2 cylinders with a distinct burble in the exhaust and smelling of gas. Not producing much power and making me shift down to 2nd to get up the (steep-ish) hill on my driveway (3rd used to work fine). Accelerates slowly in neutral, but revving smoothly once it got there. Wanted to debug it, but seems like I always had higher priority stuff to do since it started and ran. Then last Friday, (just as I needed it to pick up hay bales!) it failed down to a mode that sounds like its running on 1 cylinder. Almost like an old hit-miss stationary engine. Impressive, actually that it will idle that way. Anyway, now it will only run at all with painstaking feathering of the throttle, and wont take a load. I can slowly work up to maybe 10 kph in 1st gear only on the level part of my drive with lots of clutch, but any slope at all and it dies. It smells strongly of gas, but no smoke visible in exhaust. I have to admit, I am daunted by the amount of vacuum lines this thing seems to have, this is probably the highest length-of-vacuum-line to CID ratio Ive ever seen. Also, I havent worked on an "analog" car engine in probably 35 years, and none have needed more than basic maintenance in 25 or so; accordingly I've gotten rusty. My first thought was ignition system, partly because in the past just about every problem Ive ever had with a gas engine has been ignition system related and partly because I cant think of anything else that would affect 2 cyls but not a 3rd. Last night I took off the distributor cap, figuring it was loose or cracked, but other than wear, couldnt see anything obvious amiss. The rotor has free motion. Was going to try the use a vacuum pump to check the advance but it was getting dark. I hooked up a timing light, but cant find a mark on the pulley to compare to the arrow its next to. All 3 plug wires do trigger the light though. The wires appear in good shape and were snugly connected, although I disconnected and reconnected them just to make sure. I figure I will get a tuneup kit with new wires, plugs, points etc just because its due. Anybody with more experience with these things have thoughts on what might be the actual problem or have troubleshooting suggestions? I would appreciate it.
Timing marks are on teh flywheel. The pointer on the front is for the cam timing, unless of course someone added a mark. G&R has a good trouble shooting guide on their web page, that does a good job of going through step by step to figure out what is wrong. https://www.grimports.com/maintenance-tips
Fly, You got me with the hillbilly part!LOL I inherited the same type of situation. I didn't see anything where you might have checked the cylinder compression. Your right about the vac. lines, it really is a crazy system in that way! If you don't have a compression tester, you can rent and return for free from most any of the local auto parts stores. (in case you didn't know) Jigs is right, the G&R sight is a real nice refresher coarse, and they do a great job explaining. Good Luck! Keep us posted! Limestone
Thanks! Yeah, I overpaid for it. The CV boots are shot, the water pump drips and the driver door window doesnt go up properly without guiding it by hand. Oh, visor is missing too. Pretty sure they had put some "stop leak" into the radiator because the first thing I did when I got it home was change all the fluids and it IMMEDIATELY started pouring coolant out of the water pump. But it slowed to a drip (residual stop-leak?) and for the last couple of years its steady at <2oz per month loss. I keep waiting for it to really break before I replace it. But at that, it was the nicest one I had seen in 100 miles, so I went with it. Besides my wife's brand new VW Jetta leaked about the same amount when we bought it and the dealer said it was fine that way whenever we complained... Anyway, I dont have a compression tester, but was looking at them on Amazon when I got the new timing light. Most of my tools were my dad's, and as I need them I dig them out - then frequently find out they don't work anymore. For example, his prized Sun timing light. Which he probably paid a week's take home for in 1973. Hooked it up the other day - nothing.
Son, this is sounding more and more like a country western song! lol!!! Just Kidding! Sorry! I had to do it! A little elbow grease and you'll whip it in shape!
Just a hunch, but from past post's maybe the timing marks are hidden by mistake , because the timing is probably advanced too far! I know, sounds crazy but it's been done! Just to find the timing sweet spot! I guess! Take a look! Limestone
OK, so it turns out if you scrape off some dirt, there's a little rubber flap on the top marked "S" such that if you remove it you can see the flywheel. Well, part of it anyway. So, the distributor is rock solid at 6DBTDC at what I am guessing is about 500 RPM, and if you rev it it moves ahead, so that seems proper. Didnt realize I would need an allen wrench to loosen the distributor, so I didnt twist it any. Next time I suppose. Checked the air filter, had a reasonable amount of dirt for a vehicle that never sees paved roads, but by no means clogged. Looked for a charcoal canister per the grimports website directions listed above, guessing the carb version doesnt have this cause I couldnt find it. Did find a vacuum tank under the pax seat and it still had lots of vacuum in it for having been off for several days, so at least some vacuum hoses arent completely shot. I pulled the plugs, they were soaked in gas, but no real carbon buildup. #3 plug maybe less gas than the other 2. Didnt think to put my laparoscope inside the plug hole while open, may do that just for kicks, dont really expect to see anything, but I guess if there's hole in 2 pistons or the valves wont shut that would would be something to know. After these steps, still only runs on 1 cylinder. Never realized how much I used this bugger til I didnt have it. Found a shoestring firmly embedded in the transmission linkage. Odd. Also, the oil smells like gas. Due for a change, anyway. Anybody have a good reference for "here is how to adjust these carbs"?
Sounds like it is flooding, badly. The oil smelling like gas indicates that there is so much gas it is running through the ring gap and into the crankcase.
Mine the purge valve on the charcoal canister gave up the ghost. It would not vent. The tank would make pressure with the vapors that would force fuel out of the tank and into the carb past the float needle. If the truck sat a Couple days it would out fuel into the gas. If it sat a month it would fill the oil pan with fuel.
drivers side ahead of the tank/ after the transmission has line that goes to the top and a line into the frame. if your tank is pressurizing you will get a gusshh when you open the fuel cap
OK, got it working again. Did a basic tuneup (distributor, rotor, wires, plugs) and it runs better now than it ever has since I owned it! Thanks for the assistance!
Oh, for F-s sake! Now the radiator fan doesnt come on! @#$! I must have knocked something loose when I changed the plug wires.
I love to see progress--good for you Flybob! (I have your exact truck, and my problem with flooding turned out to be the carb specifically the accelerator pump). You are right though---change your oil and filter. All that flooding probably dumped a lot of gas into the crankcase.
So i think i would first check the spark plugs. Then do a compression test.. But depending on what the plugs look like, Might just pull the rocker covers and look for bent push rods. maybe spin it over to see of everything appears to be moving properly. If it looks ok check for loose rocker arms.. You might get lucky with only a valve adjustment.. AND stop dogging your Little truck your just killing the engine running the piss out of it like that.. Now you sound like the Hillbilly . Paco
vacuum leaks are 85% of carb and idling problems, use a vacuum gauge or carb cleaner, carb cleaner will send the engine to high idle if you have a vacuum leak, make sure the vacuum port in the air cleaner canister is working properly, also check that your vacuum advance hose isn’t cracked coming off the distributor to the vacuum manifold tree. The vacuum manifold tree is brass on the bottom to go in to the block and plastic on top. Plastic wears out with time and will break or leak, which causes a vacuum leak. Some manifold vacuum trees are 3 or 4 port, make sure to replace it with a new one. When I buy parts I buy 3 at a time that way I have them on hand or in case they can’t get them any more. The vacuum manifold tree is located behind the carb. If you looking at the carb from the right side of the bed, it will be to your 1 O’clock tucked down inside. Remember to use a marker or different colored tape to mark the vacuum lines so you know where everything goes back too! Good luck!’
