Uremco’s Holley 1920. Just don’t do it.

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J

Joseph James

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I know carb rebuilds are iffy. My original leaked. I rebuilt it and it leaks a little. Decided to buy a rebuild from Rock Auto. I could see fuel pouring from the bowl vent. Shut off car. Could hear fuel filling carb throat and verified with flashlight. Won’t buy another. Put old carb back on and the “new” one is going back. Old leaks a little when shut off but no waterfall down the manifold like the Uremco rebuild.

FWIW I use only non-ethanol mid grade.
 
First of all many times (most?) leaking carbs are NOT THE CARB

Dirt in the system getting "caught" (imbedded) in the neoprene needle/ seat and causing leakage. "Bowl vent" is the big trigger, means needle/ seat is leaking BAD

This can of course be

Leaking brass float or "gas logged" cork / other float
misadjusted float level
worn/ bad needle/ seat or missing parts or improperly installed
bent float arm dragging on internal parts of the carb
 
There is a simple fix for that called a pressure test. When you go to buy a rebuilt, you take your pressure tester along and test the carb before you buy it; just invert the thing and pressurize to 5psi.It should hold that for a minimum of 20 seconds.
If it doesn't, move to the next one.
 
Brooks James said:
The 1920 is a factory piece of crap.
Click to expand...
IDK if I would go that far;
they worked fine when everything was new.
But after a few years, engines with them installed do get to running crappy . But part of that is also the crappy retarded timing they run.
If you take the time to fix the timing, clean out the plugged cross-over, and clean the carb out, it ain't so bad. Plus they are really borderline too lean to start with; so a lil drilling here and there and then Presto!, back in action.
It's just a carb; and heaven knows we spend hours and days tuning 4-bbls.........
 
If fuel is coming out the bowl vent then either the float is set too high or stuck. If the carb had been flipped the float needle is stuck.
 
AJ/FormS said:
There is a simple fix for that called a pressure test. When you go to buy a rebuilt, you take your pressure tester along and test the carb before you buy it; just invert the thing and pressurize to 5psi.It should hold that for a minimum of 20 seconds.
If it doesn't, move to the next one.
Click to expand...
Can’t test one from Rock Auto. You pays your money and takes your chances.

I agree it’s probably a stuck float or needle/seat problem. However, this is advertised as a bolt on and go carb, not a buy and spend a day making adjustments Uremco claims to have done.

I may keep the new one and send it to Woodruff.

The old one is a bit rich running even with mixture screw all the way in but it is drivable. My Dart is a daily, so I will run the old carb for now.

I didn’t tighten the needle seat but when I put the fuel line in. I know what can happen to the needle tip.
 
Joseph James said:
The old one is a bit rich running even with mixture screw all the way in but it is drivable. My Dart is a daily, so I will run the old carb for now.
Click to expand...
At the stock timing spec? That would be very odd unless the float level is very high. My experience is the opposite; very lean.

If you have messed with the IdleTiming, then you probably had to turn the idle speed down. And if you did, then the throttles would be too far down on the transfer slots, and you would need to enrichen the mixture screws.
But if you left the high idle, then it will be getting TOO MUCH fuel from the transfer slots, requiring you to lean out the mixture screws. That's if,
If you messed with the Idle-timing.

But if you left the Factory timing alone, then probably the fuel level in the bowl is just too high.
Here's the test;
With the engine fully warmed up and idling, clamp the fuel supply line off. And wait.
One of three things is gonna happen;
1) the engine will slow down and stall; indicating already too lean
2) the engine speed will stay the same for a long time maybe flare a lil and then make the run to a stall. This is normal.
3) the engine speed will increase steadily, then plateau, then again, make the dash to a stall. This indicates rich.
If yur looking for performance with this carb, extra Idle-Timing is NOT the answer.
As a tuner, without getting into the carb circuits, your first job is to get the transfer slot to mixture screw ratio reasonably-correct at a reasonable idle-speed;
that doesn't hesitate when you tip the throttles in,
doesn't stall going into gear, and
doesn't bang either;
and daymn the IdleTiming. Let it be what it will be. Get that done.

Then you can work on your other timings which are;
PowerTiming
StallTiming, and
CruiseTiming
 
AJ/FormS said:
At the stock timing spec? That would be very odd unless the float level is very high. My experience is the opposite; very lean.

If you have messed with the IdleTiming, then you probably had to turn the idle speed down. And if you did, then the throttles would be too far down on the transfer slots, and you would need to enrichen the mixture screws.
But if you left the high idle, then it will be getting TOO MUCH fuel from the transfer slots, requiring you to lean out the mixture screws. That's if,
If you messed with the Idle-timing.

But if you left the Factory timing alone, then probably the fuel level in the bowl is just too high.
Here's the test;
With the engine fully warmed up and idling, clamp the fuel supply line off. And wait.
One of three things is gonna happen;
1) the engine will slow down and stall; indicating already too lean
2) the engine speed will stay the same for a long time maybe flare a lil and then make the run to a stall. This is normal.
3) the engine speed will increase steadily, then plateau, then again, make the dash to a stall. This indicates rich.
If yur looking for performance with this carb, extra Idle-Timing is NOT the answer.
As a tuner, without getting into the carb circuits, your first job is to get the transfer slot to mixture screw ratio reasonably-correct at a reasonable idle-speed;
that doesn't hesitate when you tip the throttles in,
doesn't stall going into gear, and
doesn't bang either;
and daymn the IdleTiming. Let it be what it will be. Get that done.

Then you can work on your other timings which are;
PowerTiming
StallTiming, and
CruiseTiming
Click to expand...
Thank you for that information. I have not adjusted anything since I bought the car. It was regularly serviced at one particular garage by the previous two owners. I have some receipts going back to the early 1970s. For that reason, I haven’t messed with anything. The car runs well other than some soot out of the tailpipe when it’s cold. It clears up after a warm up. Small gas leak from float bowl. I have rebuilt the old carb and it was leaking worse before the rebuild. Other than that, I haven’t done anything other than drive it 24 miles a day for the past couple of months.

It’s at 96k miles. Is it time for a valve adjustment? Timing chain? I will try clamping off the fuel tomorrow evening.
 
AJ/FormS said:
IDK if I would go that far;
they worked fine when everything was new.
But after a few years, engines with them installed do get to running crappy . But part of that is also the crappy retarded timing they run.
If you take the time to fix the timing, clean out the plugged cross-over, and clean the carb out, it ain't so bad. Plus they are really borderline too lean to start with; so a lil drilling here and there and then Presto!, back in action.
It's just a carb; and heaven knows we spend hours and days tuning 4-bbls.........
Click to expand...

I would go that far, especially when 50 plus year Carter BBS carburetors still run great.
 
I love my 1920. But yeah, it took a lil work to be loveable.
but yes you should always do a valve adjustment on a solid-lifter slanty that you just acquired. I set mine cold to .018/.023, cuz that's where it idles nicest.
But slantys are tricky.
Mine have always had ruts wore in the rocker pads by the valve stems, so have had to trim my feelers to get into the ruts.
Check the timing and put it back to factory specs. There should be a decal under the hood or on the apron, detailing the specs; usually TDC to not more than 5* advanced.
The Slanty will be more responsive with more PartThrottle Timing, but I put that into the rate of advance and PowerTiming, cuz if you put it into the IdleTiming, that messes with the Transferslot exposure.
You will know it's right when you can touch the key (engine warmed up) and it springs to life with NO fuss and NO help from the gaspedal.
 
Maybe someone can tell me why fuel would be overflowing out of a vent or leaking out of a carburetor because of improper timing ?
 
RustyRatRod said:
I would go that far, especially when 50 plus year Carter BBS carburetors still run great.
Click to expand...
I dunno. I've had great luck with all of the 1920's I've had to deal with, even the glass bowl ones. I've probably touched a couple hundred 1920's and the only thing I've ever had issues with is the throttle shaft bore wear. Less than an hour of time to fix tho.
 
oliver said:
I dunno. I've had great luck with all of the 1920's I've had to deal with, even the glass bowl ones. I've probably touched a couple hundred 1920's and the only thing I've ever had issues with is the throttle shaft bore wear. Less than an hour of time to fix tho.
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I have a couple. Their in the junk pile. It might well be me. I just cannot stand the design.
 
oliver said:
Cmon. The bbd has way more moving parts and even more that are intricate small parts.
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If you like them so much, pay shipping and I'll send you both mine. One is a new reman that was a POS right from the rip I robbed some part off of.
 
RustyRatRod said:
If you like them so much, pay shipping and I'll send you both mine. One is a new reman that was a POS right from the rip I robbed some part off of.
Click to expand...
Never said I like em so much. Just that they aren't a bad carb. Only reason I touched so many is the few on vehicles I have owned and all of the ones I've worked on for customers in the past. They put em on everything.
 
oliver said:
Never said I like em so much. Just that they aren't a bad carb. Only reason I touched so many is the few on vehicles I have owned and all of the ones I've worked on for customers in the past. They put em on everything.
Click to expand...

Well, I'm fully ready to accept it's me. LOL I've just never cared for them when the Carters are so much easier "for me".
 
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