The Next Issue

[Roadster Rich]

Every step in this rebuild of the engine, surfaces another problem. I rebuilt the Tillotson carb with a kit. Now I find a pretty drastic leak at the gasket separating the upper and lower casting. I have heard that these are notorious for warping with the engine heat. I never really confirmed a good flat planar surface and the top casting is pretty severely warped. I am sure that the best solution is to machine the two to assure perfect flatness, but I am not sure where I could get this done. Is there any of the permatex products that might take up some of this warp and keep from leaking? I use the blue and black in many places, but I don't think either should be used in contact with fuel. Honestly I think the warp is so bad that nothing would resolve this. My other solution is to use a rebuilt Zenith I got two years ago that will not work due to such a bad sloppy throttle shaft fit. It came to me from a rebuilder I will not mention, and is the worst slop I have every seen in a throttle shaft. The car would start but would not stay at an idle, it was pulling in so much air. Maybe buying one of the oversize shafts or getting new insert bushings would help me to resolve this so I at least have a carb to get the engine started. Also when you get the bushings, is it clear what size reamer I would need to enlarge the holes for the bushings?

I am going to sell this car to the father of a friend and have promised him I would finish to get the engine running well, and he can take the car the rest of the way. I don't intend to do a "work around" that leaves him with a problem.

Rich

[tbirdtbird]

another reason they warp is because the bolts are overtightened.
It almost sounds like the needle and seat are not closing properly.

Renner's corner is the all-time best bet for an overhauled carb that is fool-proof. An upstanding father-son place.

http://www.rennerscorner.com/index.html

[tbirdtbird]

Purdy you are purdy quick on the keys!!!!

[Mickey]

Renner's doesn't do carb. overhauls anymore.

[Roadster Rich]

Thanks for the feedback. Yes it must be that the float is not shutting off fuel, but it was leaking so badly that it cannot be left that way anyway. I will try to prove out the float shut off, I did set it at the 1 inch height for my "X" model. But the pin may not be making the seal to the seat.

Does anyone know what the size should be on the shaft for the Zenith throttle rod? The one on my "rebuilt" Zenith is 0.0272" and the bore it fits through is 0.0293" I know you can buy oversize shafts but none of the sellers show any information about what diameter they are. I think I am best to fix up the Zenith I have rather than continue to put time and money into the Tilly. I would need to know if I should put in bushings to get back to the original shaft size or ream out the carb and use an oversize. Easy decision if I can just find out what size they are so I can get a small reamer.

Rich

[Roadster Rich]

Excellent. Thank you for that information. I will order a standard and the bushings and then install the Zenith.

[BILL WILLIAMSON]

Valve grinding compound on a plate glass, "levels" stuff quite well. If you oil & cover it, it can be used again & again! (TIP# 137)---NO, I don't have a list, I jist "make up" NUMBERS--LOL
Bill Flat

[Roadster Rich]

Thanks Bill. But in this case the warped top half has raised areas above where the seal to the bottom half is. The only way would be to machine with a small cutter and move around the surface to avoid the raised area. Did not look to me like the way to go just to use this Tillotson. I should have the new oversized throttle shaft and some bushings today to finish the Zenith and then get this engine started after 30 years.

[tbirdtbird]

good luck!

[Mitch]

On a few Zenith's I first used just the over-sized shaft, since it requires a smaller sized drill bit to install than using the Bushing's. If that ever wears out I would then use the standard shaft with the Bushing's

[Tom Wesenberg]

I had a stuck valve strip a fiber timing gear. That was part of the reasoning to using them

I agree. Back in the late 80's I worked on a farmer's swather with a Wisconsin air cooled V4. These were famous for valves sticking during the off season, and this farmer's V4 snapped the camshaft trying to move the stuck valve. This is why it's good to pour oil down the carb to pickle the engine for storage.

[Mitch]

AER builds his motor with the fibers for that reason

[tbirdtbird]

If you put MMO in your gas your valves will not stick
I have had a bunch of vintage cars for close to 35 yrs and once the lead was gone, in went the MMO. I have never had a stuck valve of my own or on a customers car.
If a car needs to go into long term storage, then get fogging oil from your local boat shop and fog it out thru the carb while it is at a fast idle. Get ready for a cloud of blue smoke. But the internals of the engine will have a nice layer of oil everywhere it needs to be. This is done on marine engines, outboards, etc all the time

https://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=fogging+oil

dave boatyard

[tbirdtbird]

that would work really well, Purdy. If done for storage, fog the daylights out of it until it stalls. Now you have oil everywhere; and valves will have a heavy coating

[George Miller]

I agree. Back in the late 80's I worked on a farmer's swather with a Wisconsin air cooled V4. These were famous for valves sticking during the off season, and this farmer's V4 snapped the camshaft trying to move the stuck valve. This is why it's good to pour oil down the carb to pickle the engine for storage.

Yes they were bad about sticking valves. In my Dads garage we got some every year at harvest time. I also fixed one that they broke the cam shaft trying to turn it over. We always told them to shut it done at the end of the season with oil in the carb. But some times they forgot to do it.

[tbirdtbird]

valve guides must have been too tight from the factory

[gpowers]

another reason they warp is because the bolts are overtightened.
It almost sounds like the needle and seat are not closing properly.

Renner's corner is the all-time best bet for an overhauled carb that is fool-proof. An upstanding father-son place.

http://www.rennerscorner.com/index.html

Tbird, I am having similar problems with my Tillotson as well. When I bought the car it would idle ok but sputtered and died once I got it up off idle. Being a new Model a owner, I did a lot of looking online and felt comfortable taking it apart. Once apart, it had a little sediment in the float bowl but otherwise I thought it looked good. I cleaned it up and put it back together but it still had the same problem so I decided to order a rebuild kit. In the interim, someone suggested I try loosening the fuel line, rotate it upwards, and blow bubbles back into the fuel tank. Wasn't sure if he was pulling my leg or not so I tried it and it solved the problem. When the kit came in, I decided to try my hand at rebuilding it according to the instructions. The float was less than an inch so I adjusted it. When I put it back together, it did the same thing as Rich's. It leaked between the top and lower castings. I snugged the screws but have not over tightened them. It did not leak before I put the kit in either. I have had it apart several times and worked on adjusting the float and I think it's close because it doesn't leak at the gasket any longer. Today when I was driving it it seemed to sputter a little and felt like it wasn't getting enough fuel. If the idle jet is screwed out too far, will that cause fuel to leak out of the carburetor inlet? I recall the instructions saying to open 1.5 turns when I put it back together but when I did that, it really leaked fuel out of the inlet. I only had it open about 1/2 turn so I opened it another 1/2 turn and it seemed to drive fine but I got a few drops of fuel dripping out of the inlet. Could the fuel leaking out of the inlet be a problem with the float needle not seating as well? Thanks in advance for your time.

[tbirdtbird]

Don't know where you got the kit from.
Generally, especially with today's polluted fuel (ethanol) you are best off with the viton tipped needle.
Sometimes the jets have too many gaskets and should only have one, so check for that, gas can ooze over the tip of the jet if too many gaskets
Fuel leaking between the halves can only mean one thing, the float is not set right. Normally the fuel is BELOW the seam

There are many who feel the Tilly runs better than the Zenith, I am one of them.
However, when Miles restored his wrecked slant, I gave him my Tilly and installed a Marvel which I feel is the best of all. Hard to get tho. Renner's used to rebuild all the carbs, but now they don't, you would have to buy one outright