setting he timing

Mon May 13, 2013 9:29 pm

i have a cub lo-boy 154 i need to set the timing on it can anyone help me please

thank you Dean

Re: setting he timing

Tue May 14, 2013 7:28 am

Welcome. The engine and ignition timing procedures are the same for the 154 Cub Lo-Boy as a standard Cub.

There are a number of resources associated with this site explaining ignition timing.

Top of page, select manuals, then operators manual for one of the later year standard Cub. Ignition timing is explained with photos. Manuals are a free down load.

Search function at top of page. Many discussions on Cub ignition. Should also should be a video or two on timing the Cub.

I didn't exactly answer your question. Where are you at in your ignition timing effort? Distributor out of engine? Engine moved with distributor removed? Problems with the distributor?

Re: setting he timing

Tue May 14, 2013 7:36 am

Not sure if the tractor is able to run or not so I'll start with the beginning. This assumes that your tractor has a 16 degree timing mark and a distributor. All 154's were shipped with a distributor ignition system, but I don't think that all had both timing marks.

Turn the engine over by hand until the #1 cylinder is at TDC on the compression stroke.
Verify that the timing mark on the crankshaft pulley is at the pointer. (clean the timing mark up so it's easy to see) I clean and use white-out to brighten it up. Also cleanup the 16 degree timing mark.
Remove the distributor cover and verify the rotor is pointing to the spark plug wire that connects to the #1 cylinder. (This should be approximately at 1:00)
Put distributor back on.
Tractor should be able to get running at this point.

Connect a timing light to the #1 cylinder and connect to a power source if necessary.
Loosen hold down bolt on base of distributor. (just barely loose enough that you can turn the distributor)
Start tractor, run at full throttle no load.
Using timing light to observe the timing mark, adjust the distributor by rotating it until the 16 degree mark is at the pointer.
Tighten distributor hold down bolt.
Idle down tractor.
Observe the timing mark with the timing light again. The 0 degree timing mark should be near the pointer. Do not adjust to make this occur, just observe. If the 16 degree mark is at the pointer, then there is a problem with the distributor advance mechanism.
Shut off tractor.
Remove timing light, reconnect spark plug wire, and tighten distributor hold down bolt.

If you have a way to check the RPM's, this is a good time to do it. Make sure that your engine RPM's are matching the specifications for the tractor. If you have to adjust the RPM's, then you should recheck the timing again.