1947 Cub no compression

[old]

So I got the carb and linkage in today. Put the carb on and rigged up a small gas tank to test start it. I has good spark and gas flow to the carb but little to n suction at the air intake. I tested compression on a couple of cylinders and had zero compression. Tried to fill the cylinders with ATF ad n 2 ATF ran out of the carb. Put all the plugs in and pours some ATF down the exhaust and had ATF out the carb again. So I am thinking I'll have to pull the head off due to sticking valves.

Does i sound like I am on the right track??
Thanks

 

[steve_in_mo]

Cub flathead engine would have a plate on the side of the block to adjust the valves.
There's a video of a cute girl doing the adjustment on YouTube.

 

[old]

I know about the plate but if the valves are stuck open no adjustment in the world will help. I figure I will have to pull the head so as to be able to tap on the valves to free them up maybe

 

[C.Amick]

Could someone have had the engine apart and got the pistons and valves out of time?

 

[old]

Doesn't appear to have been opened up but if it had been it appears it ran since then. So good chance this is caused by the fact it has sat a long time and it didn't have a carb on it either

 

[Jim Becker]

Take the tappet cover off the side and pull the spark plugs. From the side you can see which valves are sticking. Put a good quality penetrating oil on the valve stems through the side. Go through the spark plug holes to get some onto the valve stems from the top. A squirt can works for this. Since the stuck valve will be open, getting penetrant onto the side of the valve head should allow the oil to run down to the stem. Do this several times over a couple days.

Then try pushing the valves down using a screwdriver through the spark plug hole. (I haven't tried this but have been told it can be done.) If they aren't stuck too badly, you may be able to avoid pulling the head.

 

[BarnyardEngineering]

If the valves are stuck you can see that via the plate. It is also remotely possible that someone has the valve lash adjusted much too tight and the valves are all being held open.

 

[old]

The cylinders are full of ATF which is one of the best penetrating oils there is so there soaking right now. I'll have to look closer to see if I can see the valve by way of the spark plug holes but it didn't look like I could so I'll look a bit closer

 

[old]

This cubs appears to have been running then the person pulled the carb due to some sort of carb problem and never got back to it.

 

[steve_in_mo]

That's probably your best bet, assuming that stuck valves are the problem. If not, taking the head off will probably let you look for the next most likely problem.

 

[old]

I have very little of a back story on this cub. What I was told was it was owned by a guy who died then his widow sold it to a friend and I have i to see if I can get it running. I hope to buy it from my friend cheap. Or he will own me a good bit of $$ for parts and labor

 

[tn terry t]

you can look through the spark plug hole and see both valves . i have never had to remove a head to free them up on a cub engine. there is enough room that you can take a rod of some sort and set on top of the valve ang give it wack a time or two after you added your favorite penetrating concoction. you might have to turn the engin over to push them back open and wack them a couple different times

 

[old]

I'll have to take my headlight out tomorrow and look a bit closer. Some how old age and seeing is getting harder

 

[grandpa Love]

My wife's purple cub had all but one valve stuck when we got it. Took head off, gasket is $15, took side valve cover off. Made a gasket for it. Took 3+ weeks of spraying it almost every day with penetrating oil and rolling it over with hand crank. Lightly tapping valves. Finally all of them worked. Decent compression. Cub runs great.

 

[old]

Head gasket from O'Reilly's is $17 LOL . Not sure yet if I am going to pul the head or try pushing them down by way of the spark plug holes

 

[504]

I had an 8N with three stuck valves,going through the side covers I freeded them and ran it.