new engine runs too rich HELP!!

PV is original and it has back fired so as soon as my new one gets here I will change it out. Also, when I screw the mixture screws in it keeps running as if nothing has changed. Hopefully the new jets and pv will arrive tomorrow. Also I will reset the timing and adjust it up a bit. It's strange because when I first started the engine up after the rebuild, it would idle fine and rev up good. It has only been run in for an hour or so.

Ken do you belong to the Penn-Ohio group? I met some of those people last year up in New Phillie or in that area.
 
I belong to the NOMAC (Northern Ohio Model A Club) based in the Cleveland area.
I have several customers in Penn-Ohio.
We will be having several tours this year, perhaps you could make it up for one.
 
BTW, the intake manifold you are running is the best single carb manifold on the market. My Tudor's engine was used as a dyno mule to test the various intake systems.
At this point, see if you can borrow a Stromberg carb to try. Bolts right on.
K
 
Don't forget plug gap can affect timing . Gap too close --plugs can get sooty , above .035 --advance or hotter plug .
My A was showing hot plugs & timing etc was right on , but plugs were around .037 to .039 whereby gapping them to a tight .035 brought a nice light brown color .
W/ all of your mods, maybe plug gap should be non standard ?
 
FWIW, I once had a PV that had the threads on an angle. The valve itself was good but w/the crooked threads it didn't seal when screwed in to the body.
 
94's use vacuum secondary's which look for low vacuum to indicate you are doing 30 and want to be doing 70 which is where the problem lies. Model A's are a low vacuum motor. Have people run 94's on them absolutely some block the secondary completely and choke down jets so she runs right but then no secondaries when you do need it. Whats a fellow to do? Stromberg 97, buy set .44 jets and the secondaries are mechanical (Yeah problem solved) I pretty much have same engine as you I just bought the BIG97 stock jets are .45 which another friend of mine runs and he ended with the .44's. I bought a pair when I got mine, my friend bought from .33 up to .45 and tried them all. Now I don't have to, and neither do you. 94 and 97 use same manifold bonus!
 
Re: new engine runs too rich HELP!! Up date111

Well, after looking at everything and trying most suggestions from here, I got to rethinking the symptoms. What I thought was a rich condition was actually a lean condition. When I first fired the old girl up, it ran well. After playing with the carb and timing, it started to change. It would only idle with the air cleaner on or when you partially hand chocked it. Plugs were black as soot, burned your eyes and hard to breath.

I reved motor up and closed the butterfly 8-10 times. What ever was plugging up the idle circuits must have broken lose. It now idles at 450 with no help. I did change main jets out to .045.
Didn't check the vacuum but intial start up show 16-18hg. Still have more work to do but making progress. I can see a 97 in my future.

Thanks again for all the suggestion and help. I will update as I make changes.

Jim
 
Call Don Baxter at Baxter Ford Parts in Lawrence, KS. Best Stromberg carb guy anywhere

If you need his #, call me

Steve Becker
Bert's Model A Center
800-321-1931
 
Y is correct I used wrong term
the 94's use vacuum actuated power valve that needs to be blocked/changed to keep it from opening too soon. It's not rocket science, but it can be a pain in the *** to get set up so the setup works right. 97's have a mechanically actuated PV that opens when the accelerator pump plunger reaches the bottom of the bore. No guesswork about when the PV opens! Otherwise, they're both just 2bbl carbs...
 
"Well, after looking at everything and trying most suggestions from here, I got to rethinking the symptoms. What I thought was a rich condition was actually a lean condition. When I first fired the old girl up, it ran well. After playing with the carb and timing, it started to change. It would only idle with the air cleaner on or when you partially hand chocked it. Plugs were black as soot, burned your eyes and hard to breath."

When you first said the exhaust burns your eyes, my first thought was a lean mixture. I've been behind cars that had vacuum leaks and the lean mixture can really stink and burn your eyes even if you are behind them a car or two at the stop light.
 
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