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Wed Mar 19, 2008 5:28 pm

I know you guys can help. I'm replacing the 30pict carb with a rebuilt 34pict3. Not a factory reman, just rebuilt. When I first ran it, it flooded over when I tried to idle it down. I pulled the top cover off, removed the needle/seat unit, cleaned it out and reinstalled. No more flooding, but now it won't idle. It does for about 45 seconds or so, then drops rpm's and dies. It will start right back up, but won't idle. I've messed with the fuel/air mix screw and the larger idle screw. What's next?
I'm not much on carbs. My idea is to run the 34PICT with an SVDA dizzy, which I have a brand new one ready to install once I get this buggy to run right. Oh, it's a 1600dp all stock.
Thanks, fellas.

Wed Mar 19, 2008 5:59 pm

I forgot to mention that the buggy ran fine with the 30PICT carb on it, just has that awful dead spot that's common with that carb and the 009 dizzy. I want the 34PICT/SVDA set up. [ I really, really want dual Kadron's, however, I still have a front end to rebuild, single master cylinder to convert and disc brakes to install---someday!!!] Money-money-money.

Wed Mar 19, 2008 7:05 pm

OK I'm no expert but I do seem to be able to tune my cars so they run well.

Where do you have your fuel/air mix screw? Idle screw?
Change only one thing at a time, and work slowly. Start with the air/fuel screw. I'm trying to remember the base to start at. Turn air/fuel all the way in and then come out 4 full turns? I can't remember.
Adjust the screw until the car runs at its highest idle (with out staling). Give the car time to adjust again work slowly. Once you have this achieved this then play with the large idle screw to bring the idle down. Hopefully the timing is set to where it was running good before and you don't need to bring this into the equation.

If you can't achieve this then I would start looking for a plugged idle circuit.

Wed Mar 19, 2008 8:07 pm

Is the fuel cut-off solenoid hooked up? From the back of the car it would be on the left hand side of the carb. It has a spade connector and the hot wire for it usually splits off of the wire for the electric choke.

Wed Mar 19, 2008 8:12 pm

Quote: Is the fuel cut-off solenoid hooked up?
Bingo, I'll bet we have a winner. Totally forgot about that. :oops:

Thu Mar 20, 2008 5:55 am

Choke and solenoid are both hooked up. Initial setting on the mix screw [ small screw ]was all the way in, then back out 2 1/2 turns. Initial setting on the idle [ large screw ] was in then out 1 1/2 turns. Throttle screw was set to just touching the lower step on the stepped cam. I may have to take the carb apart. Might be some crap still in there somewhere. I'm not the one who built the carb. I bought it.

Thu Mar 20, 2008 6:06 am

Vacuum leak?

Thu Mar 20, 2008 6:10 am

Thought about that. I'm still going check that out, however, I had no problem with the 30PICT that's been running on it. These forums all seem to agree that the 34PICT works best with the SVDA dizzy on a stock dual port. I'm getting rid of that dead spot and the 009, one way or another. It'll get ya killed.

Thu Mar 20, 2008 6:50 am

With a vacuum leakthe engine will run with the choke on as it restricts the airflow. One way to check would be to carfully (emphasize carefully), restrict the airflow into the carb and see if it idles. If so, the air is coming in somewhere. Watch out for the possible backfire through the carb tho. If you have a leak a propane torch appears to be a good diagnostic tool (although I have never personally tried it). Just turn it on a little and pass it around some possible vacuum leaks sources and listen for an idle improvement.

Thu Mar 20, 2008 8:19 am

My guess is a vacuum leak, most likely at the throttle shaft. No worries, it can be rebushed.

Also make sure that idle cutoff solenoid is actually clicking when you put power to it. If the gasket that goes between it and the carb body is too thin, the plunger won't retract (no click). If this is the case, back it off a few turns and try it again. If it works this time, put a thicker gasket in there. I also put a SMALL DAB of blue Locktite on the threads, as they like to back out, which causes the engine to die on deceleration.

Lee

Thu Mar 20, 2008 8:23 am

By they way, the 34PICT 3 / SVDA is a GREAT combination! Once you get it all tuned in, there should be NO flat spots or hesitation. I think you will be very happy with it. If you want even more power, I suggest installing a CDI module for improved ignition.

Lee

Thu Mar 20, 2008 9:36 am

Will do. All this is very good advise and that was exactly what I was looking for. At least it narrows things down a bit. I have my new SVDA setting there waiting to be installed, once she'll idle on her own.
I never though for the propane idea. That would certainly be alot safer than the starting fluid I've heard people using. That's just plain scarey.
See you fellers later, and again, thanks so much.

Mon Aug 25, 2008 10:15 am

Maybe this will help,
http://www.aircooledtech.com/34pict3_modification/

Mon Aug 25, 2008 10:55 pm

rebuilt...are you sure it was done thoroughly?

I had a similar problem (wouldn't idle) with my non-rebuilt-been-sitting-for-some-time 34PICT, problem was plugged low speed jet which didn't clean out even with carb cleaner & air hose. Finally got it cleared with the smallest size tip cleaner for my ox/acetylene welder. It would then idle but still ran like $%&&**! until I did the mods as in the link above. I plugged the hole in the throttle plate with a #8 or #10 screw & nut (peened the nut over REAL good so no possibility of it coming off). I also did not drill out the low speed jet until later & noticed a real difference when I did.