wright stander kawa 17 hp head gasket +governor problems?

Discussion in 'Mechanic and Repair' started by Dave's, Aug 29, 2010.

  1. Dave's

    Dave's LawnSite Member
    from KC MO
    Messages: 5

    Short version: Head gasket on one cylinder is blown. It was reading 0 psi with a compression test. However, the other cylinder was only reading 30 psi. Also, the other day the RPM spiked crazy high (friend suggested governor could be the culprit). Now at half throttle the mower is faster than it was at full throttle. Would replacing the gaskets fix all my problems? What should I be replacing while I have the engine this far apart? Also, below there is a picture where the pushrod was rubbing on the block? and wore in a spot. Is this a big deal? Could there be a crack somewhere? ANY HELP IS GREATLY APPRECIATED!


    So for months now I've had to use my mower with smoke and a slight amount of oil (enough to get the valve cover and a little bit of the deck dirty) coming out from around one of the valve covers. It would mainly just pop a little smoke when you started it but that was it. THIS IS IMPORTANT> THE ENTIRE TIME IT HAD FULL POWER. SINCE THE DAY I GOT IT LAST YEAR TO NOW, IT HAS THE SAME POWER OUTPUT. I just didnt have time to mess with it so stupidly I kept mowing with it. Yesterday, I was mowing along and the RPMs seemed to spike super high, So i shut it off. I let it cool, then tried starting it again. At that point, at half throttle the mower was operating louder and seemingly higher RPMs than full throttle before. Any idea what that problem could be?

    Since I wouldnt be able to mow with it with the RPM problem I decided to attack the head problem. First I compression tested it. On the left cylinder that had smoke coming out of it there was no pressure at all. The guage just read 0. Then I tested the right cylinder and got between 25 and 30 psi from it. On this website (http://www.ereplacementparts.com/kawasaki-fh500vas06-stroke-engine-parts-c-30157_30211_31391.html that has good diagrams for my motor, this guy commented this at the bottom " Compression should read min. of 57 psi. to around 95 or 100 psi. " so seemingly something is wrong with both cylinders. I got her all taken apart down to the head and there was an obvious problem with the gasket on the left cylinder that had been smoking which you can see here:
    You can see where the gasket was blown out at the bottom of the cylinder and if you look closely, another spot to the right of that. If you look around the actual cylinder you can match the gasket up and see the black spots where the oil and what not has been pouring through. You can also see how black the top of the cylinder is. If not here is a somewhat better picture of the area around the cylinder:

    So does that area that is blown out on the head gasket explain the 0 psi compression? What could be wrong with the other cylinder being only 30 psi? I am wondering if there is possibly a crack in the block somewhere?

    Also, I noticed that in the following picture, the push-rod on the left cylinder that was smoking, has been wearing into the block a little bit? Is this something to worry about or not a big deal? The push-rod seems to have no wear on it whatsoever.
    There you can see at the bottom of the big hole in the center where it's all worn out.

    SO, will replacing the gaskets fix my problem? With the black piston, should I replace anything while I have it this far taken apart (besides gaskets and what not)? A friend mentioned that the high RPM could be the governor but I have no idea where it's located.

    Last edited: Aug 29, 2010
  2. Jayson_109

    Jayson_109 LawnSite Member
    Messages: 129

    wow, sounds pretty darn close to what I have with my 23hp. Things did start out with smoke at start up, then noticed traces of oil from between the valve covers near all the linkages. Tried the cheap thing with a little "stop leak" from auto parts store. Just say 3 yards later a loud ping sound, just once. Then now have a nice fog machine, with oil dripping from both connections to the exhaust pipe. Even have it dripping from the end of the exhaust.
    I have taken off the valve covers and gaskets are in ok shape, did one of the push rods weren't in the proper position so I placed it where it should have been. Some say to adjust the valves since they usually need adjusted, but I think I have bigger issues at hand.

    Sorry don't have much of the tech answers you're looking for but, I know I've looked cost for parts and labor, and the purchase of new engine is about the best solution.
  3. Dave's

    Dave's LawnSite Member
    from KC MO
    Messages: 5

    I definitely had big gasket problems on each side. Local stores only had 1 gasket in stock so hopefully in the next couple of days I can get both gaskets on and figure it out. I have been tinkering around using the 1 gasket and I believe I have full compression back in each cylinder but have to test that with an additional compression tester to verify (the one I have is kinda sketchy, I'm gonna buy a new one tomorrow.)

    I'm thinking the high revving relates to the 0 compression on the one cylinder. I'm hoping that after just putting all new gaskets on everything I took apart and putting her back together she will be back normal. We shall see. I will post up anything I find out.
  4. BigFish

    BigFish LawnSite Platinum Member
    Messages: 4,004

    So if I'm reading this right, you used/torqued the same headgsk. twice to check the comp.? You should plan on installing two new ones, cause ya ruined that one.
    You should also pull the heads apart and check the giudes and valves. If they check out, then you need to lap the valves.
    What is causing the pushrod to rub??? That ain't right!!
    Count on tearing the whole engine down, 'cause the gov. sounds like it's out to lunch also.
    A lot of your problems stem from having seriously dirty cyl/head fins. They need to be cleaned on a regular basis. Does the term AIR COOLED not mean anything???
  5. Dave's

    Dave's LawnSite Member
    from KC MO
    Messages: 5

    Yeah, I was planning on using new gaskets. It looks fine still but 4 dollars for a new headgasket now is worth it.

    The valves are still seated in the heads. What are you saying I should do to them to check them out? They seem to be functioning properly. I am aware of what lapping is, but not of the procedure to lap a valve. Can you possibly explain this? Do you just mean take them into to have someone lap them or is there a way to do it myself?

    In the thread on the other site, someone said that the rocker could have been not torqued down properly allowing the rod to move out of place a bit. It sounds possible I guess. However I don't plan on replacing the block JUST for that so it's just gonna have to stay that way I guess.

    Honestly, I am not super experienced with all of this, so it's just a guess...but I am just hoping that the engine running while 1 cylinder had 0 compression is the cause for the spike in revs. We'll see.

    I kept the mower clean as much as I could (especially recently with a blown head gasket lol) but had no idea how much of a mess it was underneath the plastics. From now on I will definitely try and come up with an efficient method to keep her cleaned up better.

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