5 replies to this topic

[fujii13]

can someone refer me to pics of exactly where the points of adjustments are on a USDM CVCC carb for a 1.3L? my technical manual literally says "bring the carb to dealer, the only ones who have the equipment to adjust it".

i find that hard to believe and would like to adjust some of my settings to get a better ride (esp in the cold), but i have no place to begin and could really use some direction.

thanks in advance.

[Omega Mugen]

Are you sure you don't have a Hitachi? I know the 1987 1500 CVCC carb is a Hitachi. I don't know about the 1300.

Hitachi Tuning Guide

[Fennec]

Does your carb look like this? (This is JDM CVCC keihin carb but almost exactly the same as the USDM carb)

Yours should have more "stuff" on it like electric choke and float vent, but this carb is the only one I have off the car for picture taking.

That means it is a Keihin and not a Hitachi. The reason why the tech manual says to bring it to a dealer for adjustment is that they need to cover their a$$es because messing with the carb will mess with emissions compliance.

The main things you can adjust is idle speed, idle mixture, and fast idle. You can adjust other things too, like accel pump stroke, float level, aux throttle angle, choke angle and dashpot/idle controller speed. But I think the main things you wanna mess with is the idle speed/mixture.
This is the back of the carb (facing firewall):

Again, this carb will look a little different from yours but the adjustments are in the same place. See circled yellow? That is idle speed, I always like to bump it up a little (800 to 900rpm) to keep these older engines from stalling sometimes in cold.
The circled red is mixture setting. On the USDM carbs, it is covered by a plate that is only removable by taking the carb off the car. The website that Omega listed above (Hitachi Tuning Guide) will give you a primer on how to adjust idle mixture...

Hope this helps

[fujii13]

Are you sure you don't have a Hitachi?  I know the 1987 1500 CVCC carb is a Hitachi.  I don't know about the 1300.

i thought it was but i could be wrong. this is on a 2G civic, but carbs are so similar and the guys at civic1200.com all refer to here anyways.

[Chris_12v]

My 87 1.3L US came with the 3bbl Keihin. I might be able to round up some pics, if so, i'll post them.

Chris

[fujii13]

it looks VERY similar to that. the idle speed knob is EXACTLY the same for sure but i'm going to have print these pics out just to make sure.