mid teens carburetor rebuilder

[John Kelso]

Any recommendations  on a good carburetor rebuilder for a high end car?

[Larry Schramm]

John in Missouri.  He is on this forum under carbking.  https://forums.aaca.org/profile/81337-carbking/

[JACK M]

I think Jon is good for info these days.

He has made it clear that he doesn't work on them any more.

[John Kelso]

That is correct he is not rebuilding, I checked.

[John_S_in_Penna]

However, since carburetors are his specialty,

he may know others who expertly rebuild them.

Maybe he can refer you to someone, if you ask him.

[John Kelso]

I did John and he had no recommendation.

[nickelroadster]

The Old Carb Doc in Nebo N. Carolina redid an old Schebler for me that works real well.  We also had some good discussions about an old teens Johnson carb and he seemed to be quite well informed.

[John Kelso]

thank you

[TTR]

On 11/17/2021 at 11:18 AM, JAK said:

Any recommendations  on a good carburetor rebuilder for a high end car?

What type/year of car and/or carburetor ?

Edited November 23, 2021 by TTR (see edit history)

[John Kelso]

1917 Pierce 38

[edinmass]

If it's not missing parts, there isn't much to it. I would recommend taking it to a shop thats familiar with brass cars, and can jet it for you. What makes you think it needs a rebuild? If it's leaking your fuel pressure is probably too high.

[Grimy]

Those carbs have an adjustable main jet, controlled by the knurled round knob on the steering column.  No need to re-jet for ethanol fuels.  Just clean the carb and main jet out out, replace the packing around the main jet's gland nut (consider using a refrigeration [non-oil-sensitive] o-ring).  These carbs also have flat, spring-steel "reed valves" at the fresh air intake which must NOT be mixed up, and you can merely clean each set with aerosol carb cleaner and reinstall exactly as found.

 

Hopefully you're still using the pressurized fuel system rather than an electric pump.  My 1918 48 needs 1-1/4 lb psi on the dash gauge for a cold (or hot) start.  If you have trouble getting to that level of pressure, check the gas tank cap seal, which was originally lead but most have now been replaced with refrigeration o-rings (LARGE ones).  PM me for more info.

[Walt G]

Isn't it just great that we have P-A guys like George and Ed here to walk you through the proper way to sort out things step by step on your own ?  Be very thankful that the opportunity to read and then digest all you see here that you select to do is available from the comfort of you home with your car most likely a few steps away. It is worth the annual dues for AACA just for a months worth of a "good read" about all the topics , much less a years worth.

[edinmass]

George, by jetting it, I meant using a five gas to tune it properly. In this case, adjusting the main jet. Obviously, checking the entire ignition system top to bottom would also be included. On this system, I didn’t remember the adjustable main.......I just work on too much stuff........but over pressure is a common issue (I did remember that part.) for the cars dumping fuel and running poorly. There are a bunch of ways to deal with that.......some easy, some not.

Edited November 24, 2021 by edinmass (see edit history)

[Grimy]

56 minutes ago, edinmass said:

George, by jetting it, I meant using a five gas to tune it properly. In this case, adjusting the main jet.

OOOOKKKAAYYY, Ed 🙂  I'd really like to have a 5-gas readout on the dash...  Of course, we have to tune it as we drive.  Adjustable main jets are found on all (at least--I don't know enough about pre-1915) 1915-1928 P-As except for 1928 Series 81.  Cold start enrichment in my balmy area is 1/8 to 1/4 turn CCW (towards "heavy" = rich) using your right hand (i.e., viewed from RH side of the car), then lean out as it warms up.  These cars, especially the dual valves 1918-1928, need to run richer than a 5-gas analyzer will tell you.  Above 35 mph and when pushing to half-throttle or beyond for climbing hills, richen it up a bit more.  As a test, at 30 mph on the level in top gear, suddenly floor the accelerator; if it pops back or doesn't immediately respond, another 1/8 turn--or more-- rich is needed.

 

On the 2018 Glidden, we climbed up to Sun Valley (6,000 ft) and periodically leaned it out, while fixed-jet cars were belching black smoke.  Conversely, down the hill necessitated enrichening the carb.  And Cedar Pass on the Modoc Tour has a summit at 6,205 ft.

 

1 hour ago, edinmass said:

but over pressure is a common issue (I did remember that part.) for the cars dumping fuel and running poorly

The pressure pump should deliver 1.5 to 4.0 lbs pressure when the engine is running, per the manual, but 2.0 at a run is plenty.  If it's consistently too high, you need a weaker spring in the pressure pump.  In my experience, the Series 32/33/36 pressure pumps need much more frequent periodic cleaning than those thru 1920.  I've only had to clean mine once in 8,000 miles.  Be sure to carry a telescoping magnet (small diameter) to be able to remove the check ball.  A shot of brake cleaner or carb cleaner, with nozzle, will fix that problem.

 

I've developed the habit of cranking down the gas tank cap by hand (I don't use the factory-furnished "wrench") before starting the car, especially after a trailer ride, as the cap seems to vibrate loose just a hair but that's enough to stop you.  If you don't do that, all your pumping of the pressure plunger will have been for naught.  That's probably due to the refrigeration o-ring that forms the seal.  These are NOT vented tanks!  Keep at least half a tank or you'll wear your arm out doing the initial pressurization. 

 

The most frequent cause of a leaky carb is the deterioration of the packing in the gland nut which retains the adjustable main jet.  You MAY be able to tighten the gland nut a bit (there's a locking tab), but if that works prepare to replace the packing soon.

[Walt G]

OK, the last two posts you just read certifies what I stated - this is the place!

Two good guys and great advice about great cars, and how to make them work the best so you can DRIVE THEM.

Walt

[edinmass]

George, they make five gas machines that are portable.....IE for running down the road. That said, I’m surprised you have to adjust you 1918 that much under normal driving conditions. The Rolls Royce cars also all have mixture adjustment from the steering wheel. Unless changing to a significant amount of altitude, we almost never adjust them. Obviously you want to keep it running rich.......melted pistons and burnt valves tend to get expensive. I have driven a bunch of Pierce cars from 1910 to 1928..... usually only a short or medium distance......not the thousands of miles you have run in them. I expect that your basically live at sea level, and I’m sure you tend to get into the hills and mountains and have elevation changes that come much faster than we do back East. I find most early cars cold blooded and thus I tend to fast idle them till they are at full operating temperature. Next August, I’m going to visit you again before Pebble, and probably before the Pierce meet. Looking forward to a ride in the 18. 

[Grimy]

31 minutes ago, edinmass said:

That said, I’m surprised you have to adjust you 1918 that much under normal driving conditions

Well, I admit to a little OCD to keep it plenty rich--as you know, dual valves can develop hot spots that can result in a cracked valve seat.

 

Next year, give me a day's notice so I can have the 1918 in the yard when you arrive--not like this year's 20-minute notice 🙂 .  And we'll do lunch....

[edinmass]

Will do, I figured half the adjustments to the mixture were “the joy of tweaking the car for your enjoyment, more than performance.” Hot spots around four valve cars was a common issue......in my White, they angled the valves for better flow AND better cooling and it also allowed for a higher compression engine.......it’s stated in their announcement of the engine. It must have been common for cracks to develop in the mid teens with the multi valves, because they felt it necessary to announce they had solved the problem. 

Edited November 24, 2021 by edinmass (see edit history)

[Grimy]

9 minutes ago, edinmass said:

Will do, I figured half the adjustments to the mixture were “the joy of tweaking the car for your enjoyment, more than performance.” Hot spots around four calve cars was a common issue......in my White, they angled the valves for better flow AND better cooling and it also allowed for a higher compression engine.......it’s stated in their announcement of the engine. It must have been common for cracks to develop in the mid teens with the multi valves, because they felt it necessary to announce they had solved the problem. 

The Pierce dual valves, especially through 1920 with detachable jugs, were a modification to existing castings because the Packard Twin Six and the Cadillac V8 had much better volumetric efficiency than the single-valve Pierces.  Dual valves greatly improved the VE.  So they crowded two 1.5-inch valves per side, and there's very little meat between the valve seats and the deck at the top of the cylinder bores.  That worsens if the engines have been bored over the years, resulting in essentially a sharp edge at the intersection of the bore/deck/valve seats.  Best Practice for rebuilding a dual valve engine is to sleeve it back to standard (4.5" on a 48) or even 1/16 smaller than standard (you won't feel the difference), and then chamfer the top of the bore to a 45* angle with the deck, so that there is no "sharp edge" to quickly heat up.

Edited November 24, 2021 by Grimy
fix typo (see edit history)

[Walt G]

 A lot of what you are reading in the discussion between George and Ed may be "over ones head" so far as understanding exactly what they are talking about BECAUSE we don't have that particular car and carburetor in front of us or have had the opportunity to look at one ( I only wish as do most here I am sure) but just reading what they say- several times for me! - starts to get you to think , that alone is so important, and draws you into the conversation. Thanks again Ed and George for you taking the time to share what you know with all of us. Preservation at its best, indeed.

Walt

[John Kelso]

Grimy and Ed thanks for the information. This is an original car that has not been restored and I don't think run since the 50's. The chassis is covered in

grease and grim from day one in 1917.  The three blocks are broken from freezing and need repaired. The carburetor is thick with varnish. I am doing the

basic rebuild and 20 years ago would have done it all myself but due to the limited time I have left wished to move things along a bit faster by contracting the

accessories to other competent people. I want to drive this car this summer. Thanks again.

[edinmass]

JAK - Who you choose is very important, pm me with your phone number. Best, Ed

Edited November 24, 2021 by edinmass (see edit history)