1450- New to me, won't start. Pulling my hair out!
 

I bought a 1450 this weekend. It was 2 1/2 hours away, but a decent deal and I've been wanting/needing something with a hydraulic lift (for tiller, blade, etc..) for a long time.

I get to the place and find out the guy is a recently retired International dealer, had rebuilt and over-bored the engine himself. It supposedly had about an hour of run time since rebuild. I drove the tractor around a bit, felt real good about the deal, loaded it, blade and snow blower on trailer, and happily brought it all home.

At home, I use the tractor to pull the blade and blower off the trailer and to the barn, put the deck back on, fire it up again, start the deck up, it mows about 10', it bogs down, backfires a couple times, and dies. I start it again, start the deck, same thing, bogs down, backfires, and dies. Start again, try to make it to my shop, backfires multiple times over about 20', dies, never made it to the shop, wont start at all now.

I pulled the side panels and air cleaner off, notice immediately that the carb is spitting gas while I turn it over. I remove the carb, take it to the bench, disassemble, nothing noticeably wrong, give it a good cleaning, make a slight adjustment to the float, factory set the needles, and put it back on.

Now there's no spitting gas, and after a few unsuccessful attempts to start, there's a fine fog of fuel fumes in the intake.

Here's a list of what I've done the last couple of days (In no particular order):
Checked for spark by laying plug on engine and cranking over (multiple times, and after every major change).
Ensured there was no arc at the points (multiple times).
Set and checked the timing by static timing method (checked multiple times).
Ensured 12v running to coil with key on.
Tested coil resistance (good).
Installed known to work coil from my 680.
Tested for continuity of spark plug wire (had some resistance, replaced with good wire).
Installed known to work condenser.
Watched through intake port and spark plug hole to ensure valves are moving correctly (they seem to be).

No matter what I've done, I get the same scenario. Engine cranks just fine, sometimes sounds like it's firing, sometimes puffs a little white smoke from the exhaust, has a fine fog of fuel in the intake, with no excess fuel build up that I can see, but still won't start at all.

I'm already admitting that I've been had by this supposed expert. But I took the deal, so I'll deal with it.

I don't know a lot about these engines, but I know enough about engines in general to guess that it's boiled down to a compression issue.

What's next? Do I need to tear apart this fresh, dealer rebuilt engine? Start with the valves then check the piston rings? Or is there something obvious, external, that I'm missing?

I own 5 Kohler K series engines, and I've never had this problem, and never had to do any internal engine work.

Thank you in advance, any input will be greatly appreciated.

Something simple if you haven't already, try changing spark plug, I've had engines that won't even start, maybe pop every once in a while, but no start. Then when I change it it runs like its brand new. Something to try. Even if the plug looks good, doesn't mean there might not be something wrong with it.

I did not read that you replaced the spark plug. It could be fouled after the backfire issue. Seems like whenever I have backfire issue, I adjust or rebuild the carb, always replace the plug and they fire up for me. I would replace the plug with a new one and try again.

Cub Cadet 123

pull the line off the carb and make sure its flowing properly

Ya plugs can do the most silliest things. It can go from not letting an engine run good, to not even being able to start. And its something so simple, everyone just goes over it without changing it. I've done it before. Even if the plug looks good, change it anyway. Knock off one more variable.

Thanks for the quick responses, I have not changed the plug. The one on there has no fouling, and produces a nice bright spark, so even though I changed a few working parts, I overlooked changing the plug. I don't have a new one on hand and live 25 miles from the nearest town, but I'll check in the morning and see if the same plug is in the 680 (that runs fine) and try that.

Olds45512- Yes I checked fuel flow. Getting nice clean fuel from the line, and after cleaning carb blew through all holes to ensure they were open as should be.

I have not seen you post for a while sg. porter. Good to hear from you again!

Cub Cadet 123

Thank you! It has been awhile. It's a long story about shattering my spine and becoming disabled that doesn't really belong in this thread, but yes, it's good to be back around, and able to do a little playing with my cubs!

Well that does not sound like fun! Been dealing with back problems my self and it p*sses me off the most when i cant take a ride across the yard on one of my stiff riding cubs without being laid up for a week. Good luck to ya with the back situation.
Have you done comp. test? When i do a rebuild I will run engine for a while to get nice and warm and retorque head. i did a rebuild on a buddys shovel head last year and he did not bring it back after he took off with it, end of last years riding season here in up-state ny, and his first ride this spring he blew out brand new gasket after just 100 miles.

Check your valve adjustments.

Sounds like everything else is in order. From the description, I'd say valve issues.