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View Full Version : John Deere 165 carb/engine problems. Help


jason6586
08-12-2010, 11:54 AM
I have a John Deere 165 hydro that has a Kawasaki FB460V on it. I cleaned the carb because I thought the float was sticking but it still doesnt start. It seems to be spitting raw gas back through the carb. I took off the intake manifold and when i hold my hand off of it it pushes compression back through the intake valve? Is there supposed to be some that comes back, I thought It was only supposed to suck fuel in? Any help would be great

Thanks

BigFish
08-12-2010, 12:45 PM
Probably has a stuck/bent valve. pull the valve cover off and you'll see the pushrod is not in the rocker arm socket. If the valve is stuck you should see that the valve/spring pack is sitting lower than the exh. Need to pull the head, replace guide etc.

jason6586
08-12-2010, 03:26 PM
Well i pulled the valve cover off and didn't see anything sticking open. I pulled the head off as well. I dont have any stuck valves but It doesnt seem like the intake valve is tight to the seat. When its on its compression stroke its fully seated but i can still spin the valve. Could the valve be warn enough for this to happen. I dont think I should be able to spin the valve while its in the fully closed position.

dutch1
08-12-2010, 05:46 PM
Pull the valve from the head and examine both the valve and the seat. If you don't have clean ring where the valve and seat contact, the valve is likely not seating properly. Could be just carbon buildup on the valve face or seat. Check for side play of the valve stem in the guide and also note that the guides are the same height as they do tend to move when they are overheated/lack proper lubrication. Worn valve stems or guides contributes to eratic seating.

jason6586
08-12-2010, 08:19 PM
This engine is not a OHV, Can I just take the valve out and grind off a few thousands of an inch from the stem to make it seal?

dutch1
08-12-2010, 08:41 PM
While you're this far down you might as lap valve/seat then adjust valve clearance to specification. Do both while you're at it.

BigFish
08-12-2010, 11:35 PM
This engine is not a OHV, Can I just take the valve out and grind off a few thousands of an inch from the stem to make it seal?

Your right, I goofed, it is a flathead. At any rate to check the valve clearance, rotate the crank so the piston is 1/4" or so past TDC on the comp stroke. This should eliminate the compression release.( if it has one)
If you have to grind the end of the valve, don't use a bench grinder! You'll end up takin too much off. I use a fine stone in my die grinder in a homemade fixture, but you can use a short piece of small angle iron as a V-block. Go slow untill you get some clearance, then lap the valve seat/s (do em both) and finish the clearance with the grinder and smooth out with some 220 W/D paper on a file, or a honing stone.
I usually smear some moly assy. lube on the valve stems on assembly.