I bought an 85 with the straight six and a c5 a few months ago. It was a one owner 84k miles no rust or dents type of truck so I couldnt pass on it.

I'm slowly in the process of building a mild 302 for it as its going to be a street truck and no hauling.

It looks like its been hacked on a bit, but me and friend went over it when I first got it, found some vacuum leaks and fixed them. Put a nut/bolt in the carb on the screw that always backs out on straight six. Did a bit of tuning to get it to run a bit better. It still was hard to start and keep running. Ran decent after it warmed up. Drank gas like crazy and didnt have any ***** at all.

So I put a new cap, rotor, plugs, pcv and the other typical stuff. Seemed like it ran a little better, still felt like 50hp though. And was still hard to start and gas mileage was still crap.

I've messed with it along with a few other people, seems like it idles way too low, but if you turn the idle up even a hair more it wants to keep running after you kill it. Mess with the air/fuel and you can get it to idle a little smoother. First start up in the morning and you cant do anything to keep it running. Second time you might. Third time you can keep it going usually. Sounds like its got a huge lopy cam in it until it warms up. The choke isnt hooked up but I've been told by numerous people that I dont really need it around where I live.

Any ideas? I just want a smooth running motor to last me til I get my 302 built. And hearing all the fans of the 300six here makes me wonder if we are talking about the same motor. 0-60 is probably what most people can run a half mile in, it drinks gas, and runs like crap for the most part. And its a low-mile truck that was driven by and old man! And on top of that I've got a lifter making noise and some other noise from the motor. Already tried the ATF for the litfter and that didnt work.

I'll take some pictures tommorow if I get a chance to see if you guys can tell if theres anything that sticks out like a sore thumb that would be making it run like this.

 

Well, that's your starting problem-no choke. Have you set the timing? If you have a light go ahead and see where it is for a reference, and then loosen the dist and while it's running, turn the dist a little bit in the direction that increases the idle speed. Just a little bit, and lock it down and see what it does.

 

Sounds like you need to thoroughly clean the carburetor and put a "kit" in it. Follow the "kit" instructions exactly and pay special attention to the adjustment instructions. There are several emissions components such as the EGR valve that can have major effects on performance . P.S. you might want to check in on the 300 engine forum for other hints.

 

problem with buying a vehicle from an "old man" is it probably didn't get driven far on any single trip so you probably got carbon build up, and sludge like crazy in the motor. change all the fluids and filters, including the tranny. pour some seafoam into the gas tank, down the carb, and down the brake booster vacuum line into the intake. if that doesn't make a significant difference look at rebuilding the carb or buy a new one.

 

Thanks for the help guys. I'm going to try seafoam tommorow. I'm pretty sure too it has lots of buildup. I took a hammer and beat on the muffler a bit the other day and I heard all kinds of junk breaking loose and rattling around in there. If that doesnt satisfy I'm going to look into rebuilding the carb and blocking the EGR off maybe and getting rid of the rest of it.

 

The running on, running like crap at idle, lack of power and bad gas milage sounds like exactly what my problem was when I bought my '85. It turned out to be two problems. #1 was a worn throttle shaft which makes putting a kit in useless. Wiggle the shaft back and forth while it's idleing, you'll see what I mean. #2 was the harmonic balancer had slipped on the rubber which made a timing light useless.