Farmall Cub

OK, I need some opinions on what I should do.

The following are the symptoms I am having at the moment.

She starts really slow and underpowered. It will take about 5 minutes to warm up but once she does she runs like a top.

I also have Blueish smoke coming out of the oil filler cap (blow by?).

I am looking for opinions on what I start to plan on doing with her this winter. Full teardown or lapping valves etc.

As a side note I am mechanically inclined but inexperienced with working with motors but not afraid to tackle something difficult with help from others.

Thank you,
Chad

Oops forgot to mention that I have used SeaFoam in the fuel and in the oil but it has not helped.

Chad

She starts really slow

Chad, are saying the engine is "Turning Over" slowly, or it takes a while for it to start?

If it seems to be taking a long time for it to fire up, I'm thinking you have poor compression, which would account for it taking longer to start as it is taking it longer to build up compression to fire. That would lead towards worn rings, valves not seating/or need adjustments, or even a bad headgasket.

I'd try doing a compression test and see what the results are.

I'm sure you already checked the simple things like good spark and such?

Sounds like it's time for a rebuild. Perhaps when things warm up the tolerances tighten enough for it to run well. I'd plan on a complete tear-down, bore and rebuild.

Chad,
Once I put some Seafoam in a gas tank and the Cub dang near quit running until I got the doctored gas used up. Later I found out why. Two of the plug wires had the down-turned portion of the plug connector missing, so the spark was having to jump there and at the plug post--just wouldn't fire most times when the additive changed the properties of the gas. New plug wires and she runs fine.
Barn_cub

First, get a compression check right now to see where you're at. It may be something simple, and it makes no sense to suffer the rest of the summer with a mistuned tractor, then spend hundreds fixing what wasn't broke in the first place.

If you've got 3-digit compression readings across the board, it's a simple tuning issue. Even in the 90's, it's not that bad.

Even with low compression, it may just need a valve adjustment. That's pretty easy to do, actually. Did mine with no prior experience in one evening.

Mine had the same kind of symptoms as your's is. It would also start puffing a little steam out of the radiator after a while. Points, condensor, plugs, wires, cap, rotor, seafoam, valve adjustment. Nothing that would hurt, but nothing really helped.

It finally turned out to be that the timing was way too advanced. That simple adjustment, and the thing roars like never before, and runs cool as a cucumber.

Into Tractors

are saying the engine is "Turning Over" slowly, or it takes a while for it to start?

I would have to say both. once it starts I have to wait until it warms up and the RPMS ramp up before I start mowing the lawn with it.

I will need to go to the auto parts store to get a compression meter (I have changed the plugs since the issue started but will check what they look like again and re-gap if necessary.

Thanks for the help.

Chad

Perform a complete tune-up. That will rule out or correct the common bugs that hinder performance.

I will need to go to the auto parts store to get a compression meter

Now don't let your wife know I forced you into buying more tools now

Be sure to check the simple stuff though. If the engine had been doing fine, then all of a sudden started doing first this; be sure to check for the simple stuff before digging into it deep.

Be sure to check the ignition system out and of course the fuel system as well.

If all seems to pan out, then it's time to go further into it. You'd be surprised at how simple a fix can be. Had a cub show up at BD's for CubTug. Rick Prentice did the magic on the carb right there in the open and did a rebuild on it. Carb got put back on, engine wouldn't start. Ended up the points & timing were off. A few adjustments, and it ran like a top.

That's right. I forgot to mention that I also partially re-did the carburetor. Partially, because I have a weird Zenith with adjustable main jet, and could only use some of the parts. Also, the carb had been recently rebuilt, or was nearly new, if I'm not mistaken.

Chad, Come to Cecil's cubfest in the fall.Learn to do a valve job. Pick Cecil'd brain while you are there. Ed

I think that maybe the pickings could be slim. But we're still doing the valve job.

Cecil's brain is good pickins. Ed

Cecil is a spook... sometimes what you pick needs a security clearance

sometimes what you pick needs a security clearance