This can't be good

[Berwil]

I've been having trouble with a sticking exhaust valve since the end of last summer. It sticks open about the time I'm finishing mowing and I've had to push the tractor back to the shed 3 times including last week. Starts up a few hrs later no problem.
Today I cashed in my "what do you want to do on Father's Day" for garage time (I'm a stay at home dad, I get plenty of time with my daughter). I had bought a new head gasket over the winter and decided today I will decarbon the head of the tractor. Before I loosened the bolts I tried to tighten them first and was surprised that the two on the front of the engine near the exhaust valve moved. I opened it up and it looked to me like there was a small head gasket leak, no biggie, got the new gasket. I rotated the engine to inspect the cylinder walls and was saddened by what I saw. No deep vertical grooves, but a horizontal line of markings on the right hand side of the cylinder wall. I cleaned everything up the best I could and put it back together. My question is, am I going to loose my engine soon? The markings are not deep or sharp, but I could feel them through the nitrile glove I was wearing. I'm not an engine guy, this has me really nervous. Thanks

image.jpg

Bill

[J-Mech]

Bill, I've torn lots of engines down with markings on the cylinder walls. It happens. At some point in the engine's life, it sat. May have even been slightly stuck at one point. As long as it isn't burning oil, or has pitting in the cylinder wall, your good. For whatever reason, those abnormalities just stay there. Won't hurt a thing. Fix your exhaust valve and put it back together. Pull the valve all the way out. If you have any questions, I'm sure we will be right here.

Stay at home dad huh..... Want a job?

Dilbert.jpg

[Berwil]

Thanks Jonathan, puts my mind at ease! It doesn't use oil, it barely moves on the dipstick between oil changes. Aside from the sticky exhaust valve the motor runs great. Since We're discussing it, what's the best way to clean the valve and guide?

Yup, stay at home dad. I thought it would be great have plenty of cub time while she napped etc....some days I don't even get the dishwasher unloaded. I wouldn't trade it for anything though, it's nice when you can send your "boss" to her room. HaHa

Bill

[J-Mech]

Mineral Spirits or Laquer thinner. (Parts solvent) Wire brush on the head. A bench grinder with a wire wheel is fine FOR THE HEAD ONLY. On the stem, brass brush and the solvent. On the guide, a brass brush and some WD-40 would work. You can use the solvent there too, but put a rag in the lifter cavity to soak up the cleanings. I have little brass brushes for cleaning valve guides. Go to a hardware store and see if you can find something that will fit in the hole. Even if it has nylon bristles it will work. Just don't use steel. (steel/wire bristles) Pull and clean both valves while you have it apart. Remember, POST PICS!

[jimbob200521]

Originally Posted by J-Mech

Mineral Spirits or Laquer thinner. (Parts solvent) Wire brush on the head. A bench grinder with a wire wheel is fine FOR THE HEAD ONLY. On the stem, brass brush and the solvent. On the guide, a brass brush and some WD-40 would work. You can use the solvent there too, but put a rag in the lifter cavity to soak up the cleanings. I have little brass brushes for cleaning valve guides. Go to a hardware store and see if you can find something that will fit in the hole. Even if it has nylon bristles it will work. Just don't use steel. (steel/wire bristles) Pull and clean both valves while you have it apart. Remember, POST PICS!

Good advice, John! And please do post pics! I've never done valve work before so the more info I can extrapolate from other peoples work, the more confident I will be when I do my first valve cleaning. Good luck, btw!!

[Berwil]

Thanks Jonathan, will do!

Originally Posted by jimbob200521

.....I've never done valve work before.....

Me neither, trial by fire I guess. I'll get pics and post the outcome when I get a chance.

Bill

[DoubleO7]

Originally Posted by J-Mech

On the stem, brass brush and the solvent. On the guide, a brass brush and some WD-40 would work. You can use the solvent there too, but put a rag in the lifter cavity to soak up the cleanings. I have little brass brushes for cleaning valve guides. Go to a hardware store and see if you can find something that will fit in the hole. Even if it has nylon bristles it will work. Just don't use steel. (steel/wire bristles) Pull and clean both valves while you have it apart. Remember, POST PICS!

If'in you have a gun cleaning kit, see if any of the bore brushes can be used.

[Berwil]

Originally Posted by DoubleO7

If'in you have a gun cleaning kit, see if any of the bore brushes can be used.

I do not, but I like the out of box thinking!