Kaw FH500v, What am I doing wrong?

[dunoon2]

Hi, a neighbor has a JD Lx 277 with a 17hp Law FH500V. It was leaking oil between the crankcase halves. Removed engine opened up and found the gasket had been sucked inside.sucked inside. Waiting for gasket and seal. Finally got back to work on it and it and the workbench had collapsed and the cam had fallen out. So using the Law service manual, removed the push rods and replaced the cam with the timing cards lined up. Reassembled, and adjusted the valves ASPER manual and checked the coils and flywheel everything OK. Tried to start and it's hard to start and runs like crap, backfires thru the carb and won't some up to speed. Thought timing was off, so torn the engine apart again and nope, the marks were right on, tried it again still the same results. What am I missing? Any help would be greatly appreciated. Thanks

[hanz63]

Is it possibly some crud in the carb that had floated around when the engine was inverted?

[KE4AVB]

Could have damaged one of coils. Anything possible they go bouncing...

Also won't hurt to come up with a better work bench setup if you can. I know it is hard to spare the change sometimes but will prevent things like what happen here. Nothing else a few good cement blocks and an used pallet. Whatever that is stable. Here I use my 17 cu ft lawn cart with a pallet setup to fit across it for a temporary portable bench though I prefer my steel work bench for heavy items. I even used a couple 55 gallon drums and a sheet plywood from time to time.

[dunoon2]

The workbench was a good store bought plastic one, the guy forgot to put up the piece that secures it from collapsing. So thats what happened. I don't think it's a mag when it runs it doesn't sound like it's only hitting on one cylinder. I like the idea of the carb, I'll have to check that out.

Thanks for the replies.

[Luffydog]

Try pulling one plug wire off and see if it dies if u pull it off number 1 and it dies then number 2 is dead.

[KE4AVB]

The workbench was a good store bought plastic one, the guy forgot to put up the piece that secures it from collapsing. So thats what happened. I don't think it's a mag when it runs it doesn't sound like it's only hitting on one cylinder. I like the idea of the carb, I'll have to check that out.

Thanks for the replies.

V-twin don't sound off when off load. I get them in here where the only complaint is that when the OP engages the deck the engine doesn't run right; yet you can drive the mower around without especially hydrostatics. I had one last year that had only dropped 200 rpm when the plug terminal was bad.

[Luffydog]

I had one that would even mow but not to good it just the customer two or three times of on and off then it would go he just thought it was the grass. It was firing ok but but wasn't firing under compression. I have two test lights one for each side and compare the brightness one was bright and the other was dim. Coil was weak and at times wasn't firing under compression. One month later replaced the carb out. Turned out that the tank had plastic shavings in it that got to the carb. Cleaned tank new lines filter carb and warranty claim. Then wam bam thank u man and haven't had it in since. Saw him and said running good.

[KE4AVB]

And those pieces are nearly clear when wet with fuel. Only seen the plastic once but I have seen the sealer of welch plugs in those cube carbs plugging passages several times which is why I don't use a sealer on these when I replace the internal welch plugs. Got to where I inspect the metering chamber with a magnifier.

I even had grain of sand plugging one idle jet on a Nikki 2 barrel back in 2015. I though I was never going to get it out. Such small orifice that finding a wire strand that would pass was the problem.

[Luffydog]

Sure can send a lot of time cleaning and running back and forth to the dunk tank plus on and off time on those 2 barrels