HELP - 6x4 Backfiring and No Start

[afavia]

I purchased a 1998 JD 6x4 with Kawasaki FD620D Liquid Cooled engine that will not start and only backfires through the carb when starting attempt.

I have completed the following:
1. Compression tests show 175/180
2. Flywheel rotated to TDC on each cylinder and valves adjusted to 0.010
2a. I made sure of TDC with a screwdriver in the spark hole.
3. All push rods and rockers checked and confirmed ok.
4. Valves and rockers operate as should with starter motor, cam gear must be ok.
5. Spraying starting fluid in carb or directly in intake only can achieve a backfire through carb / intake
6. Spark / Fire tested and successful at each plug. Verified against block and with spark plug tool.
7. Fuel verified and confirmed at carb. Electric Fuel Pump.

Next Steps I am planning:
1. I ordered new spark plugs (NGK BMR2A)
2. I ordered a new carb
3. I will clean out the spark arrestor and muffler.
4. Planning on pulling the flywheel and checking woodriff key.

I am honestly stumped on this. I have good air, fuel and spark. I have tried with choke, air filter removed, carb covered with hand, spray, etc. Also, the oil is overfull and thin but clean and correctly colored. Possible fuel in gas tank from starting attempt too many times without firing?

Any help would be appreciated.

[racerone3]

sounds like ignition timing is off. check for a sheared flywheel key.

[ARGOJIM]

I purchased a 1998 JD 6x4 with Kawasaki FD620D Liquid Cooled engine that will not start and only backfires through the carb when starting attempt.

I have completed the following:
1. Compression tests show 175/180
2. Flywheel rotated to TDC on each cylinder and valves adjusted to 0.010
2a. I made sure of TDC with a screwdriver in the spark hole.
3. All push rods and rockers checked and confirmed ok.
4. Valves and rockers operate as should with starter motor, cam gear must be ok.
5. Spraying starting fluid in carb or directly in intake only can achieve a backfire through carb / intake
6. Spark / Fire tested and successful at each plug. Verified against block and with spark plug tool.
7. Fuel verified and confirmed at carb. Electric Fuel Pump.

Next Steps I am planning:
1. I ordered new spark plugs (NGK BMR2A)
2. I ordered a new carb
3. I will clean out the spark arrestor and muffler.
4. Planning on pulling the flywheel and checking woodriff key.

I am honestly stumped on this. I have good air, fuel and spark. I have tried with choke, air filter removed, carb covered with hand, spray, etc. Also, the oil is overfull and thin but clean and correctly colored. Possible fuel in gas tank from starting attempt too many times without firing?

Any help would be appreciated.

Remove the anti dieseling solenoid and check for proper operation, while it is out before fuel flows from the hole in carb.
Report back.

[afavia]

I rented (2) two jaw pullers, however the 1st one (5 ton) was too small, and the 2nd one (7 ton) was too think to fit behind the flywheel and the block. Anyone have a trick to get the flywheel off without using a hammer and pry bar?

[racerone3]

back the flywheel nut off till the threads on the crankshaft are just under the surface of the nut. hit the nut with a hammer fairly hard, sometimes 2/3 times. never use a puller, or a prybar. pullers often break the flywheel, and a prybar can crack the block or trash the magnets in the back of the flywheel. often with the nut removed you can see if the key slot in the crank and flywheel are aligned. just like this video, but skip the prybar https://www.youtube.com/watch?v=cc52RJ46di4

[Laird]

Most flywheels are drilled and tapped at least two places close to the centre of said flywheel. This is where you bolt a puller to, whether homemade or purchased. You can make them from a piece of 3/4 x 1'x5 or 6 in flatbar. You drill holes in the flat bar that allow bolts to screw into the holes in the flywheel. Make sure that the bolts are threaded in enough that you don't pull the threads out. You may have to shim the bolts with washers to get a proper length on the bolt. Place the nut on the crankshaft threads until even with the top of the crankshaft and place the bar across the nut. You can then tighten the bolts evenly until you have SOME pressure on the bar. DO NOT OVER TIGHTEN THE BOLTS or you can cause damage to the flywheel. When you have some pressure on the bar, hit it a sharp rap on the bar above the nut. You should hear or see the flywheel pop loose. If it doesn't pop loose add a bit more pressure and hit it again.

[mfenmor]

Buy a cheep borescope,
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
remove spark plugs and check cylinder walls and valves.

[Scottiechildress]

Its sounds like the valves,they will make an engine act up also confirm proper timing .The extra full oil can become an issue if timing and valves ate good remove the carb and try some fuel directly into the intake goodluck.

[Laird]

After rereading the entire post , by now maybe you have solved the problem. If not,pull the dipstick and smell the oil on the dipstick. If you have a gas smell then for whatever reason, you have gas in the oil. PROBABLY, but definitely not certain how it got there, could be from cranking it over a lot of times and not starting. If everything is as supposed to be, as in good compression, which you have, proper timing, which you are attempting to check, good spark, and fuel, changing out the spark plugs may be all you need to do to start it. Your plugs may show spark if you are checking them out the usual way of grounding them out and cranking the engine but may not work properly under compression. IF you have a gas smell ln the oil you can sustain damage to the engine if you run it like that for even a short period of time. I believe I read in someone's post , hat you don't always have to pull the flywheel to check the flywheel key. If you get the nut and washer off you should be able to see if the key is sheared or not. If everything is as it's supposed to be, you may have a bad coil, although they GENERLY either they work or don't work. Sorry for the long winded reply, but these small engines can be very frustrating.

[afavia]

I was able to remove the flywheel with a harmonic puller. To my surprise the woodriff key is actually a part of the crank and not seperate? I cleaned everything up and took the opp. to replace the plugs and again re-seal the carb with new gaskets and gasket sealer. It fired up! I have no idea what I did to correct this issue, as nothing else was really improved or changed?