I would rebuild the engine. The FC420 was the best engine that Kawasaki made. Install rings, check connecting rod, clean the head, lap the valves, and it is good to go. Buy a rebuild kit from Pat's. All the seals will be included. You will get that mower going again for 250-300 bucks!!
It finally died JD F510
- Thread starter SHOZ
- Start date
If it's really bad, skip all the panther piss and use an oxy/acet torch... Best way ever! That is of course if you have one.
If I were to use it again it would be without the mower out front. A towing machine. Never really had any issues with the motor or drive unit. Once in a while it would puff out a lot of smoke at start up but only once a year or so. Biggest hassle is the directional cable and it's more than likely my fault as I don't let it naturally brake and was using it as a brake by reversing 
About every 5 years. I finally cut out a section on of the plastic over where it's mounted for access. It's a 15 minute job now but you do it where it breaks.
I would like to get it going again for that but my work days are short. I don't have room in my shed for it and the new one I don't think. Maybe without the deck out front. It is not easy to move without engine power. Not a good freewheeler.
About every 5 years. I finally cut out a section on of the plastic over where it's mounted for access. It's a 15 minute job now but you do it where it breaks.I would like to get it going again for that but my work days are short. I don't have room in my shed for it and the new one I don't think. Maybe without the deck out front. It is not easy to move without engine power. Not a good freewheeler.
Guessing here, but possibly you could simply replace the cylinder head with an OEM or aftermarket unit. If the valves are not bent, you could get just the bare head and swap the valves/springs over. Probably a few hours work in total. I don't think you even have to remove the engine from the machine.
I'd guess from how clean it is, that there is near zero internal wear and a rebuild is not necessary.
I'd guess from how clean it is, that there is near zero internal wear and a rebuild is not necessary.
A little OT, but does the engine / transaxle share the same oil on the F510? Cool machines. I don't see too many of them anymore.
Those 17hp kawi singles are great engines. We had one in our ~1992 model year JD GT262.
Those 17hp kawi singles are great engines. We had one in our ~1992 model year JD GT262.
Yes the share the same oi but it is some how segregated as you cannot drain all the old oil out at once. I use to do a double change to get all the old out but the oil would hardly be dirty. Finally went to a once a year 2L change. Got a oil filter adapter on it and run a oil cooler with Fram filters.
I spent about three solid hours on it today stripping things down to get to the head bolts. The directions are pretty lackadaisical and what was a simple remove two cap screws and shield, then muffler turns into rather difficult access to the two exhaust manifold studs on the bottom of the head.
I could see one and got some spray on it. Later figured out there was a bottom heat shield under the muffler that needed to come out and then I could get to the one stud and see the other. The one came out easy but the other is hard to get to directly. I finally jacked the rear end way up in the air and can crawl under it to see it good but still need some sort of wobbly extension to get to it. I'll wait until tomorrow. Then I can get to the head bolts.
It would have been as easy to take the whole motor out.
The darker fins were packed solid with fuzz. Around the front was mostly dirt. The bottom of the motor is covered in oil from 23 years of a slow leak. When I get the muffler off I'll hit it with some diesel and dawn then the power wash.
I could see one and got some spray on it. Later figured out there was a bottom heat shield under the muffler that needed to come out and then I could get to the one stud and see the other. The one came out easy but the other is hard to get to directly. I finally jacked the rear end way up in the air and can crawl under it to see it good but still need some sort of wobbly extension to get to it. I'll wait until tomorrow. Then I can get to the head bolts.
It would have been as easy to take the whole motor out.
The darker fins were packed solid with fuzz. Around the front was mostly dirt. The bottom of the motor is covered in oil from 23 years of a slow leak. When I get the muffler off I'll hit it with some diesel and dawn then the power wash.
In case my earlier prediction comes true and you've got an exhaust valve seat issue.
It could also be a valve guide issue. I saw some videos saying that can be a problem with some Kawasaki's.
It could also be a valve guide issue. I saw some videos saying that can be a problem with some Kawasaki's.
Unfortunately the fins packed with fuzz would definitely cause an overheat situation.
Yes that is what you do. They didn't design the machine for major engine work in the frame.
Got the head off the mower. Looks like it's just a stuck exhaust valve. I'll see if I can free it up today or order a used one. Ordered all the gaskets yesterday. The muffler is pretty rotted. I bought a used one many years ago. I'll dig that out. Also got a new carb and fuel pump for it I've had for a couple of years.
Can't believe how packed with dirt all the cooling fins were. No way to clean them out without major disassembly.
Mowed with the new mower yesterday and the oil was ~250F after a 2 hr mow. So looks like I'll be putting the oil cooler on it. Changed the oil at 5 hrs. Lots of sparkles in the old oil.
Can't believe how packed with dirt all the cooling fins were. No way to clean them out without major disassembly.
Mowed with the new mower yesterday and the oil was ~250F after a 2 hr mow. So looks like I'll be putting the oil cooler on it. Changed the oil at 5 hrs. Lots of sparkles in the old oil.
Got it together enough today to try and start and it's a no go. Got spark and compression, though should check the valve clearance again. So I suspect fuel didn't fire with starting fluid.
I put the old carb and fuel pump back on when reassembling. Not sure it's even getting gas or if the carb didn't get upset with the off the engine handling.
Got to go to town so that's it for today.
I put the old carb and fuel pump back on when reassembling. Not sure it's even getting gas or if the carb didn't get upset with the off the engine handling.
Got to go to town so that's it for today.
Those are famous for dropping exhaust valve seats when the engine gets excessively hot due to debris buildup around the cylinder and head cooling fins, but they are encased in an air shroud, so you would only know it is clogged up if you remove the air shrouds.
It's a ridiculous design and has to all be disassembled one bolt at a time. Must have some German in there engineering. It was clogged all the way around Entire head was encased (grass, dirt) as were the fins under the flywheel (dirt).
Can't do much around the head without taking the muffler out which is a major job with heat shields and getting to the studs. The exposed bolts holding in the muffler are screwed into the hex cap extenders for 2 lower head studs.
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I took the fuel line off coming out of the pump and it was very dry. But as soon as I put a hose on it to see how it pumped it started pumping gas so might have been airlocked? Then I remembered the coil power wire I disconnected when cleaning everything up and sure enough left it that way.
It started right up after I cleaned the old plug and tried it. I got a new E3 plug one but it isn't anything like the OE on reach.
Let it idle for a few minutes to warm up as I want to retorque the head before putting the muffler back on. I ran for about 3 minutes and it stopped running on it's own, same thing popped the exhaust valve pushrod off. Not sure why though I suspect my initial clearance checking. No compression though when cranking again.
Need to let it cool down now.
And I think the oil weeping is coming from the dipstick oring as it's sit quite loose in the well and the oi level is right there.
It started right up after I cleaned the old plug and tried it. I got a new E3 plug one but it isn't anything like the OE on reach.
Let it idle for a few minutes to warm up as I want to retorque the head before putting the muffler back on. I ran for about 3 minutes and it stopped running on it's own, same thing popped the exhaust valve pushrod off. Not sure why though I suspect my initial clearance checking. No compression though when cranking again.
Need to let it cool down now.And I think the oil weeping is coming from the dipstick oring as it's sit quite loose in the well and the oi level is right there.
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Here is the problem with a dropped exhaust valve seat. They can happen, bend the valve, go back in the head, visually appear to be in place once the head cools down, then drop again after things heat up the first time. They are an interference fit seat, once they drop the head is trash unless you can find an oversized seat (outside dia) and have the head cut to accept it.