Poor idle

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Update again:
Did the valve lash while running hot again, and did timing again and it seem to run a bit smoother. Engine ran really smooth at 8 BTDC. As I was starting the lash on 5 or 6, it back fired a couple times and then after adjusting it didn't do anything. Can't find my vacuum gauge anywhere though :( . It seems to run a bit better, smoother, but under load it still bogs a bit. Like the rpms go from 800 to about 500. What causes the rpms to drop that much?

I also removed the ring spacers on the spark plugs as suggested elsewhere .

Still sputters a bit though so hopefully the new ignition will help burn the gas.
 
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Here's the idle screw I swapped out of the carb... could that screw being tightened up damage the idle metering hole carb side?

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Still betting sinking float or needle and seat worn.

Pull economizer while running and use a measure.

27/32 give or take a bit from the gasket surface to fuel level.

Or...with the air cleaner lid off do you see fuel dribbling into the throat of the carb?
 
Still betting sinking float or needle and seat worn.

Pull economizer while running and use a measure.

27/32 give or take a bit from the gasket surface to fuel level.

Or...with the air cleaner lid off do you see fuel dribbling into the throat of the carb?


I will check fuel height tonight. I don't see fuel dribbling when I shine light down the throat. Needle and seat are new.
 
Checked the fuel height. When I opened the economizer there wasn't much in there. Started it, ran it, checked it, is was about 15/16 down. I put the vacuum gauge on the motor and it ran actually pretty smooth. I stuck it on the vacuum port for the choke pull off.
I also used the snorkel port and gave same result. Funny thing is, hook the lines back up and it ran worse.

Used a vacuum pump with a gauge on the snorkel, choke pull off and distributor. Everything held....except the distributor lost vacuum fast. It isn't the hose either. Dammit. That's 1 issue is guess.

Know anywhere to get a new piece for the distributor anywhere for a decent price?

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My vacuum advance checked with a Mity-vac didn't hold vavuum either. (52 years old when i rebuilt the engine.) I kept the original distributor but freshened it up with a new gear, etc. Then just bought a new vacuum advance unit and installed it. Can't remember where I got it, probably Rockauto, but NAPA for one has them for about $20.
 
Ok I feel like this damn thing has me beat :( . Can't seem to find the issues. Things done:

-pertronix unit and coil
-fuel pump
-fuel filter
-new diaphragm on the distributor for vacuum advance
-timing
-valve lash while running

This is what gets me. The flap in the snorkel closes on idle but revving it to, say 2000rpm, doesn't seem to open it up. Tons of vacuum as seen in above photos and the vacuum choke pull off has tons of vacuum BUT the vacuum advance hole has almost no vacuum! Is my carb gasket flipped??

Also sprayed some carb clean around with no difference seen, except: spraying in the snorkel causes it to slow down, spraying in the strong vacuum ports causes it to speed up. Spraying in the vacuum advance port slows it down. Does that help with anything ? Sorry for the verbal diarrhoea , no one near me knows anything about these cars.

My oil light flickers, probably because my idle isn't high enough I think. And putting in gear lights it right up. Something isn't right somewhere.

Also, if I pull spark plug wires the engine does shutter and shake a bit

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Sorry,
The above photo was of the fuel filter while running with the new pump.

I did a search and found that these motors pull vacuum off idle, checked that and it pulls to over 20.

I haven't driven the car since I put new plugs and pertronix in it so I don't know if it bogs still yet. So until I drive it, the complaint I have is the oil light coming on in gear. BTW, my oil pressure wire is pretty knarly and it's outside cover is splitting from the wire. I don't know if that has any meaning.

On the plus side, replace the points and coil have allowed my radio to come in super clear :)
 
Vac advance port wont have much till rpm rise.

That float setting is a bit high. But not obnoxious.

Try pulling the metering block and pulling removing the aluminum plug on top and clean the emulsion tube with good carb cleaner and compressed air . Wonder if its dirty.
 
Might as well pull the whole metering block and familiarize yourself with it. Holley 1920s are super simple carbs.

Is the spring under your float?
 
Yeah id try to really clean that emulsion tube and associated ccts.. Make sure you blow air and use a good strong carb cleaner in those passages.

Im really grasping at straws here. But rule it all out. Your choke plate is open when the engine is hot ?
 
Update :

Drove the car for the first time since the new pertronix , coil, and fuel pump install. Accelerated not bad!!!
Oil pressure was ok until the engine started getting hot. Then the light started flickering in drive. Wasn't fully lit though. In park it was ok.


When standing being the car you could hear the exhaust pffft a bit but I'm wondering if the car is try to burn off the excess build up.

I tried playing with playing with the curb idle and idle mixture screw to see of I could get something working. Was very surprised that the car accelerates not bad now.
 
If you can find it up here. I happened to find some on clearance at princess auto. Its a fuel / oil additive.

But of youre hearing pfft. It usually means an exhaust valve isnt closing...or.burnt.
 
Final Update??? Maybe for a while...unless I have another issue lol. I let the cab metering block and Changed the oil and drove the car in 35 degree Celsius (95 Fahrenheit) humid heat for a good 15 mins at 60 MPH. wow did it ever drive good compared to before. No oil pressure issue either! :) Good cooling of the coolant too. Next thing to do.....body work!
 
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