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goodoldboy
09-08-2015, 07:29 AM
So I have searched and reviewed the manual, and I am looking for someone to explain what each adjustment screw actually does.

The Mikuni carb on my 2.6l is giving me some problems. When it's warm it functions great, smooth idle, good throttle response. On cold startup it is a completely different story. I have to give it about 3/4 throttle just to get it to start, and it runs very rough. The engine shakes and will not stay running without giving it gas. If the choke plate is propped open, it will idle up to about 2k rpm though.

I have adjusted the screws with little to know affect on how it runs. I have also followed the advice on this post:
http://www.mightyram50.net/vbulletin/showthread.php/3812-86-Ram-50-2-0l-Carb-adjust-for-smog-Help
Which made it run better, but still have the cold start problem.

So I was hoping to find out what the sas1, sas2 etc actually control. And does the mixture screw act as a air bleed screw? Does that enrichen or lean out the a/f mixture?

pennyman1
09-08-2015, 06:25 PM
the choke is not setting up and operating at all - common with the mikuni carb. The choke has a thermowax element that fails, then the choke doesn't work. Finding a good one is about impossible, and not worth the trouble. Either rig up a manual choke cable, or put on a weber - that is why Geronimo has had a weber carb since 1983. Look in the manual section for the info on setting the other carb adjustments until you fix the choke issue.

goodoldboy
09-08-2015, 06:47 PM
I am not planning on finding another Mikuni or attempting to fix this one. Just wanted to see if it could be made to work until I get a Weber. I have already read how to adjust the carb in the manual section but it was very vague. I will look into rigging up a choke cable for now.

camoit
09-08-2015, 09:21 PM
You can get away with a BIG STRONG cable tie on the lever on the side of the carb to hold it open for a while, or use wire. You need to pull the air cleaner and look for the lever with the gear teeth on it. It touches the choke plate gear. Then pull that thing back real hard (it has a real strong spring) and open the choke up. It will be a pain to start but it won't suck the tank empty every 3 days.