I recently posted a thread detailing the new Jeep J-20 I purchased. It’s a 1982 and does not have the Stock 5.9l V8, instead it has a 4.2l 258 cid straight 6 in it with a Borg Tranny.
I knew upon buying it that it would need some work. The guy I bought it from was a mechanic and had several nicer jeeps and other vehicles in his little shop - and just wanted to be rid of this one.
So, on the way home after about 10 miles it began to chug.chug.chug…then stop. So I opened the hood and there was no smoke…he had mentioned that it does this so I was kind of prepared for it - I let it cool off a bit then started it and kept going. Everything in this engine is right there so when I got it up to my house I noticed some things that were a little alarming, but nothing too horrible - I hope.
The fuel pump was mounted on the frame close to the engine and NOT back by the tank…odd but not too terrible.
The radiator leaks like a sunofabitch so I changed the hose and that was that. But for the issue of the stopping only after a few miles still happens…so I am thinking there is a vacuum in one of the lines, or the carburetor needs to be fixed or cleaned…I do live at 8200-ft so that could be an issue too!
Anyway, I brought it to a mechanic buddy of mine and he corroborated that there was indeed a vacuum in the fuel line because it was replaced with substandard line, so when it heated up it would eventually give and the vacuum would close it off. So he is replacing that and all the belts - new battery etc…
My questions are this: I have not had an 80’s vehicle for a long, long time and am wondering about up keep? This engine is great because i can see everything right in front of me, unlike our little audi where everything is covered…
It’s been a while and I really want to make this jeep into a daily rider…what kinds of things ought I look out for? regular oil changes, keep an eye on the clutch, clean-up the engine really nice and watch for oil leaks or gasket leaks… Anything else? What about the drive train? Do I need to do anything on the maintenance of that?
oil leaks are a bigger one. Gasket/sealing technology wasn’t so hot back then, so engines of that vintage will tend to start seeping before too long. I don’t know if the 258 has one (I think it does) but a common place for oil to start leaking is the gasket for the lifter galley cover on the side of the block.
Check the coil and ignition module. On their way to complete failure, they often fail hot. I would flush and replace many of the fluids, perhaps going to more modern ones. I have Mobil 1 synthetic 0W-30 in my 77 truck. Unless you know they have been worked on, I would rebuild/replace the brake calipers and wheel cylinders. Also the brake hoses and clutch hose if hydraulic.
I have owned and maintained my own cars since the 60’s. I do appreciate the greater reliability of the electronic ignition and FI. Other than that, I don’t think that much has changed.
Is the 258 of similar vintage as the vehicle and, maybe more importantly, do you know what if any emissions equipment is still on it? It’s quite a different beast, diagnostic-wise, if the previous owner just slapped an old Rambler carburetor on there and called it good versus it actually having the smog-control rat’s nest intact. If the engine still has a “vintage” electronic ignition system, I’d suggest scrutinizing that with the problem you’re having right now.
With the altitude-tuning, I’ve never lived quite as high as you, but I’ve moved a couple old pieces of Detroit iron from sea level to about 5300 and was always able to get them running just fine doing normal tune-up type external carb adjustments. The prevailing back-alley wisdom was that altitude-tuning was something that was done to finicky imports, not good ol’ American trucks. But then, some seemed to hold that same attitude about tune ups and oil changes…
My last carburetored engine was an 81 Pontiac Phoenix with the cut down SBC V-6. They hung everything on it trying to meet emissions and drivability. I didn’t have too much trouble with it. My brother had an Olds with the same engine. The dealer replaced the carb due to a leaky float bowl. It took them a year to get it running right after that.
Is it vapor lock? I had a similar issue on my jeep ('78 CJ7). There should be a three-pronged in-line fuel filter just before the carb. The line coming from the fuel pump should go into the end of the filter with just one fitting. On the other side, the lower of the two outlets connects to the carb while the upper outlet is the vapor return line that goes back to the tank (so the fuel vapor can cool and re-liquefy). Since I tracked this down I have had now issues with engine sputter (now, to be honest, I have a host of other problems…welcome to jeep ownership!).
Also, I don’t know how the 258s were originally set up but if they are anything like the 401 I have, they were originally fitted with a mechanical fuel pump mounted up along the driver’s side of the engine. If you have an aftermarket electric pump, it should be mounted at the rear of the vehicle as close to the tank as possible (I have mine mounted on the frame rail just inside the rear wheel well. Those pumps push fuel much better than they pull.
As far as routine maintenance goes, my biggest problem has been with the wiring. Lots of corroded old connectors, gummed up wires, and bad splice jobs. I don’t know how comfortable you are with that kind of stuff, but I would much rather tear into the guts of the engine any day of the week than mess around with the electrical.
The 258 has 50k miles on it, so it is not as vintage as the vehicle itself.
The back brakes were just done, I’ve only inspected them but they seem good. All the brake hoses and clutch hoses have been replaced.
The carb was just “rebuilt” and when i looked at it I was impressed that it looked good, but as for the emissions stuff - I know it has a new catalytic converter, or at least a newly attached catalytic converter. I am pretty sure this was a rock-hopper, and the people who had it before me didn’t care much about the emissions.
All good stuff! I told the mechanic to move the fuel pump to the rear of the car and mount it basically right where you said to. Also, I’d much rather mess with the engine than the electrical, but sadly, I have a new dash on the way and I’ll have to mess with the electrical for that nasty can of worms. As a matter of fact, I’ll probably go to a friends house who knows electrical really well and just get it all done in one day. I hope! I don’t live close to a Napa or Checker Autoparts so I will have to make double sure I have everything I need beforehand.
