Help! Make my crank b start easy

I have a 1938 b crank start with fresh engine it is aweful to get started or to start at all. What things could I do to make easier to start. I had a 1939 b and you could crank it three times and would always start. What do I need to do. Has new plugs, good compression, runs awesome when you get it started. Have timing so it will fire early ( mage rolled close to motor ) new gas

setting the mag " close to the motor" aint good enough. You need to roll the motor over slowly until the mag SNAPS, then look thru the timing hole and see if the crank is on the FIRE mark... take the plugs out to get it to roll easier.

Turning it over slowly and stopping when it snaps is called static timing and then the TDC should be in the inspection hole. Running at full throttle and checking in the inspection hole with a timing light you should see the FIRE line to be in time. All engines are static timed to TDC. Car Truck or tractor. Proper advance is set while running.

Edited by Dick L - 09 Mar 2019 at 3:18pm

I have a 39 B that I hated until I learned how it wanted to be started. If I remember I set it to click when the pulley bolt was at 12 o clock on the compression stroke of #1 cylinder.  I cannot find any marks on the flywheel. I choke mine and have the throttle at 1/4-1/3. I have to crank it a few times to get the cylinder primed. I have rebuilt my cylinder head also. Make sure you have enough gas in it. You will learn when it is going to start by the feel when you crank it. Hope this kinda makes sense and not nonsense. ROD (NH) has a good page on his website about timing the mag. Good luck.

Edited by mdm1 - 10 Mar 2019 at 7:06am

Also manifold is sealed good and lack of air cleaner means that’s not plugged

Edited by ryanschott - 09 Mar 2019 at 5:32pm

Going back to your original post.  I would change the torque tube to one that takes a starter.  If you don't want to go that route, then I would always keep someone on hand to help pull start it!

DaveKamp wrote: Steve's right- you certainly DON'T don't want it to 'fire early'... it needs to be set per the book... no special tools, just follow the instructions. The magneto has an IMPULSE COUPLING... when you turn the engine slow, there's a clock spring that winds up, and when the crank gets past TDC, the spring latch is tripped, causing the coupling to go CLACK... when that happens, you get a nasty hot spark.With the crank being PAST tdc, it pushes the crank in the proper direction, causing it to start easy. If you set it way early, it will fire AT or BEFORE TDC, risking serious damage to you, and possibly the engine... so read the manual, set it per the instructions. Next... how's your float bowl height?  if too low, or too high, it won't play ball. How's your oil-bath air cleaner?  Can't have water frozen in the bottom... How's your valve clearances? If you set them tight, it won't be happy with you.  Did you inspect the intake/exhaust manifold?  Seal at the block must be tight, and there must NOT be a crack between intake and exhaust sides... and the vacuum port must be sealed properly.  The exhaust manifold and muffler CANNOT be plugged full of mouse mess and mud dauber clods. If you've rebuilt the engine, get the timing set right, take it out and run it up and down some hills... get the rings seated, retorque the head, recheck valve clearances. When a magneto/carb engine is set right, all it takes, is to push it just past TDC gently with the crank, on a cylinder that has fuel and air.  My '38 B takes exactly three 180 degree pulls on the handle to start... because that's what it takes to get a dry engine one freshly charged cylinder.

This all sounds like great advice. I will check all of these things once I have read and fully understand the manual.

What is the zenith carb float height by the way?

For your carb settings and adjustments check out pages 26 and 27 of the B-C section of the manual Gerald posted. You may want to download and print a copy of it for reference.

Like Dick L said works good. Done it like that for years on many different carburetors. Leon

Good Deal!

when I freshened up my 38 B engine I couldn't get it to fire by hand, everything was set correctly but motor was just cold and stiff. so I got my dad to tow it and it fired right off and now that the motor has run in alittle it cranks on the second pull of the crank! Ive never used timing marks I set it close as I can and go by ear once its running!

ac fleet, Go to the hardware store and get a stiff wire wheel brush with a 1/4" shank. With the engine running with the drill running put it in the inspection hole and clean the flywheel to shinny metal and see what you have. The stiff brush will not clean out the stamping. The spinning stiff brush will not catch on anything to cause a problem.

don't know about "B's" but the marks on my 45 are slight.

steve(ill) wrote: I have several Bs and every one had a Fire and TDC mark on them... Some are very faint as Dick said and need cleaned... THen I put a red paint mark on them after cleaning......... And I miss spoke a few days ago saying static timing was at the FIRE mark. Of course it is TDC as Dick had said.............. late night or CRS setting in ?

I had the same type brain freeze over on YT a while back. Happens to everyone.

ac fleet wrote: I have a brush and drill. I will try your method when it warms up and mud gets a bit drier! thanks!

You Have Mud??

Me to!

I had to feed hay early this morning while the ground was still frozen. This evening I had to use my walker cart to take water out. The wheelchair tires on it cut in about an inch and a half. Very hard to push with two pails of water.