Customers JD Sabre w/ a 406777 0115-E1 991117YH Briggs V-Twin Intek.
Would not start when cold w/o a shot of carb spray. Starts warm, no problem. Runs good once running.
Choke flap is operating correctly. I flushed the gas. Adjusted the valves. Went through the carb. Still no start.
Then I did compression and leakdown tests.
Compression:
#1- 75 psi #2- 105 psi
Leakdown:
#1- 65% #2- 45%
Air leaked past rings and exhaust valve on #1, just the rings on #2.
Plugs weren't perfect, but no oil fouling.
My theory is that it won't start because the compression is too low for the gas to be sucked into the airstream. The choke flap doesn't cover the throat completely, so I made a new flap that covers the opening better and it started cold. Only once, so far. I want to test it several times.
I'm going to tell the customer that his engine's seen better days.
Think this is an okay way to bandaid it for a while? Also, I made mine out of steel. The original is brass. I wonder why? Brass costs more, there must be a reason.
EDIT: I just tried starting it again this morning; no go.
I wonder if I repaired the exhaust valve leak on # 1, if it would start?