quinn132

Where else you gonna park?

Not sure how well I did on the tuning, sounds good but this is my first carb experience, anyone got any specific rochester varajet tuning tips/idle screw turn amounts/ what it should sound like?

Update, went around the engine spraying just about every vacuum connection I could find and didn't notice any changes in rpm. HOWEVER I did notice depending on how rich the carb is (it was running richer a few days ago before I got in there and tuned it) applying the brake affects the idle. Some days sitting in park and pressing the brake the rpm would go up and others it drops a little, but it doesnt go away.. makes me think theres a leak in the booster brake, the master cylinder was replaced back in November however the booster is original to the truck (Almost 40 years old!). Tried all the testing you can do with it, it still works but I think even a small leak could be enough to make the carb flood when rich. Either that or float valves a little high. The pedal also makes a hissing sound when I press it down (only time it does this). And it's not hard at all to get the pedal to the floor, in fact you have to push it in an inch or two before you even get brake response. Thoughts before I go drop $100? I'm thinking it should be done anyways as its so old

The secondary choke stays wide open as soon as the car starts. I say secondary because I believe my varajet has two chokes and I'm pretty sure the electric choke only controls this one. So it's definitely running lean while it warms up but as to whether it's causing the warm stalling I'm not sure, definitely think this is whats causing cold start problems though because a couple pumps of gas and it won't die in idle.

Said it was running last year when he parked it.. A year of weather exposure... Trying to decide if its worth buying and rebuilding then putting it in. Sounds like it would take me a long time and I need something that can get me to and from work now haha.

Thanks! Found a 94 3.4 for 300.. not sure if it will run. He said the only thing missing is the compressor and alternator. Worth the investment ?

Also, I realized yesterday the electric choke is not plugged in. Maybe this is causing the choke to stay shut? can't figure out which wire is supposed to hook up to it, is there a simple way to wire a new connection to the choke?

I do have a running 4x4 4.0l sitting in a 2000 cherokee in my drive way atm... don't need the car anymore because it got side swiped pretty bad. How hard would that swap be/ is it even worth it with 180,000 on the engine? I've read a couple threads on it but seems to me they aren't very detailed or just skim over the swap. I heard about needing to adjust the firewall with a hammer lol

I'm a little ambitious, is it a project that can be tackled in a week for someone whos never swapped an engine? I need something to get me to and from work (30 minute drives tops) I need to take the cheapest route atm but if an engine and fuel injection out of a junk yard can be swapped for the same price as a carburetor I'm game, sounds like its inevitable with these engines eventually anyways.

Set the idle a little high on the carburetor, kinda helps but it still dies once the engine is warm when you decelerate quick and won’t start up when it’s warm.. starts when cold though. I think the choke may be getting stuck/old carb parts are just worn down. Anyone know any edelbrock bolt ons or any other carbs that would work better on this engine? I’m thinking I should trash the whole thing as I’m getting fuel and spark.. tips?

Haha very true, appreciate the positivity :)

Wouldn’t happen to know which vacuum lines are the only ones I need? I’ve got a mate coming over today that’s a lot better with carbureted engines as I’ve only ever worked on the in-line 6. A good cleaning of all the fuel lines and gas tank wouldn’t hurt right? Who knows what’s built up in there the last 30 years

Whoops haha. Will check the vacuum lines today!

Oh good to know😅 is there a schematic of where the hoses go anywhere? The last person definitely took some hoses off and trashed what didn’t turn the car off as I can see where some are supposed to go but no hose... anyone have any pictures of what the engine is supposed to look like/ where hoses go?

Read somewhere on another forum this is where the fuel pump ground is (rear drivers side tail light). It was nasty so I cleaned it up. Got under the car and cleaned all the connections I could find. Car starts right up and no high/low idle.. yet, haven’t taken it for a long drive yet. Seems to die more when it’s warm. Next step is cleaning the egr and iac valves and tuning the carb!