All,

I was digging in the basement, and came across my factory 'Technician Skill Guides' pertaining to overhaul and adjustment of every Mikuni used by Mitsubishi.

The first one (and also the one 'most intact') is the carburetor adjustment procedure (12 pages). Remember, 12 pages covers ALL of the Mikunis (with feedback, w/o feedback, with ISC (cars), etc., so don't let the size fool you. I scanned it into an Acrobat file and sent it to Phil for posting in the Tech Section.

Once I get the overhaul instructions reassembled, I will scan and forward to Phil.

I can honestly say (assuming you don't have another problem such as a leaking intake manifold gasket or a broken vacuum line here or there)the factory adjustment procedure is the only way to go to ensure both driveability and emissions are met.

The Mikuni's main falldown is it's relatively small throttle bores; anybody who has ever installed a 38mm Weber on a Gen I will agree that alot of the engine's available performance is 'choked off' by the 28mm primary/32mm secondary...but such is the life of mid '80s emissions regs when every manufacturer was moving from extremely expensive feedback carburetion to relatively simple fuel injection.

Use this adjustment procedure, and it 'sets up right'...follow it verbatim (you will need an analog voltmeter---get it at Radio Shack for $8.00--and an analog tach from Sears for about $15). Also, DON'T FOLLOW THE FACTORY PROCEDURE FOR REMOVING THE IDLE MIXTURE SCREW PLUG. Buy a new 'hardened' 3/16" drill bit and drill into the plug's center (don't drill through it). Screw an appropriate sheet-metal screw into the plug and pry the plug out using needle-nose pliers under the screw head to act as a puller. By doing this you avoid the possibility of fatiguing/cracking the aluminum throttle body casting ($$$).

More later,

Rob in Hell <img border="0" title="" alt="[Smile]" src="images/icons/smile.gif" />

Thanks Rob,

Here is is:Carb Adjustment procedure

If your browser doesn't have acrobat internally, just right click and hit "save as..."

PHIL

How in the world did you find a procedure? I've been looking for one for years and the ones in the Haynes (and other generic P.O.S. manuals) really don't have what it takes to troubleshoot and adjust this carb.

I still would like to have a chart of all the vacuum readings at idle and at 2000-3000 rpm (this is the rpm range that the emissions are checked at in CO.). I would also like to have more info on the computer for a number of emission related problems. If we could get 5 or 6 people to take measurements, we could get an idea as to how well our carbs/motors are running.

Any takers?

Wow, Thanks !

I little knowledge is a dangerous thing.

- Bill

A few of the pictures came out black; is there any way to post those so that they are better?

Has anybody ever thought about using two Mikuni's, by hacking up two carb manifolds for carb bases and feeding two cylinders with one carb. Put a balance tube between under-carb chambers. You'd have to decrease the mechanical primary jet, but the ecu controlled jet should automatically compensate, and the secondary is vacuum controlled, so rejetting is unnecessary.

My scanner doesn't do the best when it comes to pictures...I'll try a rescan and see how it turns out.

Rob in Hell