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CV Carb Idle Trimming Problems

Hi Guys, Thank you! I will do what everyone suggests. It's great to hear constructive suggestions. Helps a lot!

Thanx!
Doug
 
Hello again, Well, pulled the carb off & turned it upside down. Removed the mixture screw and found the spring & O ring. But, not the flat washer that goes between them. So...ordered those from CV Performance!
Also, another issue...When removing the carb, found the usual oily mess from the head breather hose, attached to air cleaner.
The cases on the motor are Early Delkron. So, A couple of months ago, I unplugged the breather port(by oil pump) put a fitting in it with an I.D. of 5/16"...Ran this to a Catch Can. Now I'm breathing from there plus the heads! Looking at the mess...think I would like to plug the head breathing function! How can it be done? I have the 2 large chrome bolts with the ports in them. Also the chrome tube that joins the head ports together. Do they make a "solid" large bolt for these? My thoughts are...."plugging" the holes in the bolts with a 2 part Clay Epoxy(which I have). Would there be any adverse effects to closing off the head breather system, & just running the case breather system?
Thanks! Doug
 
Check your breather inside the cam chest, is the spacing right and if it is plastic check for scoring
 
It's not a problem running breather heads on earlier crank breather cases. However, you can't run the earlier non-head breather heads on the 93-up cases. My opinion would be to check the breather gear timing as Jack suggests. Also check the heads umbrella valves to make sure they're in working order. Excessive blowby would be the only other thing I can think of that would create such a mess of puking oil if the breather gear is indeed timed correctly and the umbrella valves are working properly. JMO
 
Adding to Al's info. in the above post. Engines built to be head breathers most often do not have the case breather valve (that's why the case was plugged). Not good to be sucking air into the cases, it upsets the whole scavenging system. You mentioned Delkron cases, so I don't know what your setup is.
 
Don't want to start an argument but at closed throttle, the slow jet and the A/F adjustor are the only sources of fuel; the main jet does not come into play until the throttle is open.

You mentioned that the carb has been modified with the CV Performance kit. I would return the carb to OEM configuration and start from there. I would also be looking at a Yost kit to improve the preformance once I got the carb in OEM configuration and dialed in. You might need the 48 but I am thinking the 46 should work.

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Just throwing out some info here. I agree that normally the mixture screw and slow jet produce the only fuel at idle. I have worked on lots of carbs and have always believed that statement.
But, I bought a 99 softail last year to play with, the previous owner said the carb was outfitted with a Dynojet kit but it ran very rich, I could see that by the sooty exhaust and plugs. It ran terrible rich at idle, it would make your eyes burn. I couldnt get much of a response by adjusting mixture screw so I tore into the carb expecting to find a much too large slow jet. To my surprise I found the jetting was still stock with a 42 slow and 170 main. I scratched my head for a bit, then thought maybe enrichener valve leaking by but that wasnt it either. What I did find is that the needle on the slide had been improperly installed, there was significant up/down movement of the needle when everything was put together (slide stationary). Upon disassembly, I found that no washers were used on top of the e-clip on the needle as needed to remove this movement with a dynojet needle. I installed 3 washers above the e-clip and reinstalled the spring seat, this took all movement out of the needle. Re-installed carb and it ran properly with no rich idle and I could set idle mixture properly. What I think was happening, at least in my case, was the needle would "lift" pulling a little fuel out of the main at idle due the the major play in the dynojet needle which has a much different taper than a stock one. Maybe OP can check for play in the needle. Sorry for the long post, just tryin' to give some ideas.

Now, I just finished installing an EV-27 so let the re-retting begin..........:s
 
Great point Stroker. I would also add that idle rpm's is very important. I've seen idle speeds adjusted to high to compensate for other issues. That make tuning at the "idle" condition impossible.
 
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