Novice '48 Cub Owner

[leed]

Hello all,
I'm new to tinkering with my Cub. It's been in my garage for several years now. When I put it away, the fan was siezed up. I took the fan out and oiled it as well as replaced the belts. Now I can't get the old girl running again. I was mowing the day that the fan siezed and she was running great. Any ideas???

[Brent]

Might be the gas has gone bad. Might want to drain the tank and also remove the carburetor and clean it out. Put it back together and try again.

[leed]

I did drain the tank and put new gas in. I tried starter fluid, too. I thought I would replace the plugs, If I rebuild the carburator, do I need to order a kit in order to get a new gasket; or can I reuse the old one?

LeeD

[Ron L]

leed. Welcome to the board. You can reuse the old one in a pinch IF it is in good shape & doesn't cause air to be sucked in the carb. A new one is recommended.
Check your compression. After sitting a few years, your valves could have rusted some and are sticking. If you think that's the problem, then remove the valve cover & work the valves loose with penetrant or some other good oil.
Also, it could be your coil on the mag or the condensor. Check for good spark ................

[Brent]

If you can get the gasket off intact you probably could use it. If you're going to rebuild it I'm pretty sure the gasket comes with the kit.

[Lurker Carl]

LeeD,

Are you getting spark? Are you getting fuel or flooding? Are some valves stuck open? Don't start replacing parts until you determine what's actually wrong.

You need compression, fuel and spark at all 4 cylinders for the engine to run. Determine what ones are lacking and you are solving the problem.

Let us know what you find and we can guide you thru fixing it.

Carl

[leed]

Ron,

Thanks for the advice...unfortunately, I don't know enough to know how to check the compression. I'm afraid about getting the tractor out of timing if I mess with the mag...should that happen is it fairly easy to re-time?

LeeD

[Ron L]

Yes. Fairly easy. The more you work at it, the easier it gets. Check here ... http://www.farmallcub.com/HLChauvin.htm Very good info. People here are excellent at answering your questions, so don't be hesitant ...........

[Ron L]

An easy way to check the valves is to pull the valve cover and hand crank the engine, watching the tappets move the valves up & down. If the springs aren't pulling all the valves down to seat, that's where you can work on them (don't scratch the shafts!).

[Bigdog]

If the tractor has been sitting for years and you have replaced the fuel, the most likely problem you have is that the points have glazed over from sitting all that time. Try cleaning the point with a burnishing tool to see if that will restore the spark.

[Lurker Carl]

The easiest way to check compression without a compression gauge is to rotate the engine with the spark plugs removed. It helps to have a hand crank and a helper. Make sure to number the wires 1-4 AND ground the plug wires so you don't mess up the mag! Timing will not be an issue unless you switch some wires around.

You can check for spark at each plug. Spark = no problem, no spark = clean the points.

Next, put your finger over the plug holes one at a time while turning the engine - does each one suck and blow air? If so, you have compression! If one or more cylinders do not, chances are a valve is hanging open.

Carburation is a whole different animal. Make sure you have fire and compression first.

[leed]

Well...I've finished a tune-up and still my '48 Cub (now "Gert"...in memory of my dear grandmother) will not start. I put in new plugs and plug wires, I cleaned the points, I am getting spark, yesterday I replaced the dead battery. I'm not getting fuel to the spark...no smell of gas when I took the plugs out (at least #4). Is this a Compression problem?

LeeD

[EZ]

leed,

I feel your pain.
After reading the other posts, and your latest one.....

I would have to say check the carburator, or look for a blockage in the gas tank. Those little updraft carbs are pretty testy. But yeah, also if your compression is so bad that you are not sucking fuel out of the carb then that could be a problem, but it was running and working when you put it away so that's doubtful. Did you take the valve cover off and look at the valves going up and down?

If all else fails, put a little bit of gas in each cylinder, put the plugs back in and try it, if you have spark, it sould at least fire.

[Dan Stuckey]

If your planning to rebuild your carb, only use the IH rebuid kit. I've not had to do mine, but all of these guys here seem to agree that it's the one to use.

Dan Stuckey
Altoona, Pa.

[Dan England]

leed: You might have an air leak at the junction of the top and bottom halves of the carb or at the carb-manifold junction. Try tightening the bolts to see if that allows fuel to be pulled to the cylinders. I would try starter fluid at the air inlet of the carb. Its lighter weight might allow it to be pulled to cylinders even if you have an air leak. If it fires on the starter fluid, the problem is probably an air leak. Dan