Starting with a Tillotson Model X Carb?

[29ModelA]

Are the adjustments the same as when you start it with a Zenith? I cannot get mine to idle without the choke, if I shut the choke off it starts backfiring through the carb and dies. If I lean it out to 1/4 turn after I turn the timing to about the halfway point and turn the choke off it dies.

I have a rebuild kit here for the carb, and that is my next step, but I want to make sure I am trying to start it correctly with the Tillotson.

My first Model A, and I don't have a clue apparently

[1931 flamingo]

Tillys are prone to warping, it's possible yours is and you have an air leak where the two halves meet. Others will chime in I'm sure.
Paul in CT

[PepeLoco]

I absolutely agree. I spent 2 hours sanding and filing mine to get the warp out and have a clean straight edge.

[Purdy Swoft]

Its a real good chance the flange of the Tillotson is warped, where it bolts to the intake. You can remove the throttle shaft, tape a piece of sand paper to a piece of glass or some other flat surface. move the carburetor flange back and forth over the sandpaper and it will show the high spots and in some cases the flange can be sanded until it levels up.. Any gaps between the flange of the carb and the manifold will cause a vacume leak. The engine depends on vacume to draw the fuel and air mix, up the manifold to the combustion chamber. A vacume leak would probably be the reason that you have to use the choke for it to run at all. Most tillotson carbs that I have run usually needed more opening on the GAV. After checking for and correcting any vacume leaks, I would probably try opening the GAV a full turn off the seat for first start. After it warms up or begins to lope you can close the GAV as needed. If it doesn't have vacume leaks and all is well it should run with the GAV closed to 1/4 turn off the seat.

[Dave in Boise]

look for warp and open up the gav.. Tilly's seem more sensitive to GAV settings in my limited experience

[Paul from Maine]

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Originally Posted by 29ModelA

Are the adjustments the same as when you start it with a Zenith? I cannot get mine to idle without the choke, if I shut the choke off it starts backfiring through the carb and dies. If I lean it out to 1/4 turn after I turn the timing to about the halfway point and turn the choke off it dies.

I have a rebuild kit here for the carb, and that is my next step, but I want to make sure I am trying to start it correctly with the Tillotson.

My first Model A, and I don't have a clue apparently

I found my worn out Tilly Model X ran better than a rebuilt Zenith I bought! Someone posted Tilly Model X installation and operation instructions on this site a year or two ago, perhaps that person would post them again or maybe you could do a search for them. I just got my Zenith Model 13922 in the mail when I got home tonight. I'd have it installed now, but I have to go to the hardware store in the AM to to get an adapter fitting for the fuel line. Good luck with the Tilly. I hope you can get it to run as good as mine. As you know, rebuild kits are cheap for the Tilly...I bought one, but have never gotten around to rebuilding it. I will now that I have the new Zenith to replace it! I can't wait to compare a rebuilt Tilly Model X with the Zenith 13922... I wonder which one will run better?!?

[eagle]

I have a Zenith on my car, and rebuilt tilly and marvel carbs sitting in a box on the bench. The Zenith runs so nice I haven't tried the other two yet. But, they say the zenith is for the show car, the tilly is for the go car.

[30modelA]

if you can get it started spray some ether around where the carb meets the manifold, and spray around the carb. try not to spray into the carb or air intake. see if the engine speeds up, if so theres your leak. good luck

[Brian SATX]

The choke should stay open about 1/4 of turn. You say you are turning it off a second time. Try it open the 1/4 turn.

[Patrick L.]

I happen to like the Tillotson.. As mentioned, look for and fix the 'warps' and you'll have a good carburetor once adjusted correctly.. They do have to be clean inside also..They seem to like the fuel mixture rod[GAV] open 1/4-1/2 turn.. To start when cold, I open GAV additional 1/2 turn, pull out the choke, Timing retarded[lever up], throttle lever down a couple clicks, and step on the starter.. After about 1 revolution I push the choke back in and it'll start right up.. After about a 1/2 mile or so turn the GAV back in 1/2 turn.. And all this on an old tired engine..

[29ModelA]

Well it sounds like what I was doing was right, now I just have to check for air leaks.

[29ModelA]

Well, I had it running today, (the flange was sanded) and within a minute the exhaust was glowing red, even with the GAV open to the minimum I could keep it running at without backfiring. (1 turn)

I took it off to rebuild it, any tips? I do think the flange bolts were a little loose to my liking though so that may be partly a cause too.

[Colorado Greg]

The Model A stores sell a book just for the tilleys. There is also a very good website by Mr Texas that explains alot of things.

http://members.fortunecity.com/pjsauber/TillyCarb.htm

[TinCup]

I have ran both and found that the Tillitson does run and idle better. Now it may just be my own experience with both of my carbs but most of my local club members all chime in and say the same thing. Warping and having to drill out and install helicoils are the major downsides. To start I would always open about a half and then close to about a quarter open when warm.

[Richard Wilson]

Originally Posted by 29ModelA

Well, I had it running today, (the flange was sanded) and within a minute the exhaust was glowing red, even with the GAV open to the minimum I could keep it running at without backfiring. (1 turn)

I took it off to rebuild it, any tips? I do think the flange bolts were a little loose to my liking though so that may be partly a cause too.

The exhaust should not be that hot. I would double check the timing. If the timing is correct then I would think that you have a very lean mixture caused either by trash in the carb blocking jets or an air leak. Do you have good gas flow from the gas tank to the carb? Try opening the GAV up 2-3 turns and see if that helps. I like Tillotsons but as has been said they run great when they are exactly right but it does not take much wrong to make them run very bad.

[29ModelA]

Originally Posted by Richard Wilson

The exhaust should not be that hot. I would double check the timing. If the timing is correct then I would think that you have a very lean mixture caused either by trash in the carb blocking jets or an air leak. Do you have good gas flow from the gas tank to the carb? Try opening the GAV up 2-3 turns and see if that helps. I like Tillotsons but as has been said they run great when they are exactly right but it does not take much wrong to make them run very bad.

Yeah, when my father said your exhaust manifold is glowing I walked around the car and saw the muffler was too

I believe I have good gas flow, the bowl was staying full, and I have a new line from the bowl to the carb. The bowl is new even.

I had a rebuild kit here already for the Tilly, so I took it off the car and brought it home. There was a little sediment in the bowl, so I cleaned it up and tore it apart. I have the carb body soaking in the parts washer right now. I put pressure to all the passages and jets and got good flow through all of them.

I think it may have been an air leak, as the carb bolts did not take much effort to loosen, just over finger tight. They may have loosened a bit on me. I guess I will see how it runs when I re-assemble it.


Edit: Holy crap you can see the muffler glowing in this video, and the car had not been running only a couple minutes!

http://youtu.be/79_vpqcho8U

[Purdy Swoft]

Now that you have the flange flat the carburetor is probably ok. I wouldn't try tightening the carb. flange bolts very much. Overtightening is what causes the flange to warp and the aluminum threads to streech and strip. The manifold should never get red hot. I'm thinking that the problem could be three or four things. Check the points gap first. I set my original style points at .022 .. next the timing. I remove the spark plugs to make it easy to turn over to find the timing mark.. Here is how I time mine . When the timing pin drops in place loosen the dist. cam screw so that you can adjust the way that the tip of the rotor points. Align the trailing edge of the rotor tip with the number one spark plug wire contact in the dist. cap, with no clockwise back lash. This is where the rotor tip needs to point after tightening the dist. cam screw . Backlash is the free rotation back and forth movement in the dist. shaft, I'm not reffering to possible wear in the bushings or shaft. some will have as much as 1/2 inch of rotational movement. Backlash in the counter clockwise direction doesn't effect the timing. Clockwise backlash causes the timing to be retarded and the exhaust manifold to glow cherry red after idleing for a while. If after setting first the points and then the timing in this manner, if it is still backfiring, the float needs checking. If the float is set too low it won't let enough gas enter the bowl before the needle valve stops the flow and starves the engine. Such a lean float setting would cause back firing and loss of power and over heating. I don't remember the exact float setting for a Tillotson,I think it is one inch. I usually hold the upper half of the carb., upside down in my hand and just adjust the float so that it is about level, this will usually apply to most. If it stalls apon brakeing you can set the float a fraction lower so as to lower the level in the carb.

There is a good chance that you could be over retarding the spark lever. For over fifty years, I have cranked my model A with stock engine with the spark up and mostly run them with the spark fully advanced at speed. If it sat idleing for a long period of time with the spark fully retarded, besides running hot it will damage the babbit. Good luck.

[Ron in Quincy]

You might try installing heli-coils in the upper body to manifold. Over the years many of the tops have stripped threads and difficult to tighten carb to manifold. Rather than take a chance I install heli-coils when rebuilding the Tillotson.

To remove the warp in the upper housing, disassemble the carb completly, bolt upper and lower housing together without gasket, put two large adjustable clamps around outside of carb bodies and tighten down until warp is removed. When the wife is gone for a few hours, put the carb in the oven at 350 degrees for i/2 hour; remove from oven and let cool for a couiple of hours. When you remove the clamps you will find the warp is gone.

Ron

[Patrick L.]

If the manifold flange threads strip, I don't worry about it.. I drill 'em and install bolts/nuts.. Sometimes once the flange is 'unwarped' the throttle shaft will want to bind upon remounting to the manifold.. I tend to run the bushings a bit loose just for this problem..

[29ModelA]

Well, I rebuilt the carb last night, and put it back on. Now I can't even keep it running. It won't start without choke, and I cannot turn the choke off or it will stall. Heck it still stalls after a 15-20 seconds anyway. The float is set perfect, and I cannot find any leaks anywhere.

I think I am going to replace all the interior fuel lines now and the shut off, I am wondering if it is getting starved.