stuck exhaust valve

[AroniaFarmer]

I have an old Wisconsin single cylinder engine that I got from an auction. It didn't have any compression so I pulled the head off expecting a stuck valve. And that's the problem. I soaked it with penetrating fluid and after about 20 minutes I got the valve to go down by hitting it with a hammer with some padding in between. But now my problem is that the valve is still pretty much stuck and now I can't move it at all because it is closed. Any help?

 

[DJ54]

If it's on the exhaust side, how about trying air pressure. Shouldn't be too hard to neck down in pipe size to attach a male end air coupler, with female threads.

And shouldn't there be a access plate to get to the lower end of the valve..??

 

[AroniaFarmer]

If it's on the exhaust side, how about trying air pressure. Shouldn't be too hard to neck down in pipe size to attach a male end air coupler, with female threads.

And shouldn't there be a access plate to get to the lower end of the valve..??

yes I have already taken off the plate that reveals the valve springs. I have sprayed lots of penetrating oil in there. Not too sure if my air compressor can do the job. Its really stuck, even prying on it with a screw driver doesn't budge it. I will give it a try though.

 

[Jerry/MT]

Spray the guides with brake cleaner. If you can get to the guide area,use a small brush and work the brake cleaner all over the stem and try to get it in the guide. Keep doing it til you disolove the varnish and it moves freely. Don't be in a hurry. It took years to build up so be patient so you don't damage anything.

 

[KubotaSam]

You can't get it to open by turning the flywheel?

 

[Soundguy]

i agree... though I see intakes stick mor ethan exhaust.. I'd work it up and down using a dead blow hammer and soemthing like atf plus a solvent penetrant. even acetone.

 

[AroniaFarmer]

You can't get it to open by turning the flywheel?

No I can't. moving it counterclockwise will make the flywheel stop when the valve is suppost to open. Going clock wise will just make a loud click and will keep turning.

 

[AroniaFarmer]

 

[AroniaFarmer]

You can't get it to open by turning the flywheel?

No I can't. moving it counterclockwise will make the flywheel stop when the valve is suppost to open. Going clock wise will just make a loud click and will keep turning.

 

[Gator6x4]

If you can rotate the crankshaft and the exhaust valve does not move I think you have a problem with the valve tappet. The tappet rides on the camshaft lobes and is forced upward which in turn opens the valve, the spring then closes the valve. You should be able to compress the spring (small engine repair facilities sell a tool for this)on the valve and remove the keepers which will allow the valve to be forced up and out. If a sharp blow was deliver to the valve when it was partially open damage probably occurred to the lobe on the camshaft.

Without knowing the model number of your engine I selected a single cylinder engine for reference. Scroll down and look at part number 132. This is the tappet. The view also shows how this interacts with the camshaft.http://lib.store.yahoo.net/lib/yhst-77226736812062/s10d_s12d_s14d.pdf

 

[MHarryE]

Back in the old days I tried turning over our Owatanna swather equipped with a Wisconsin V4. When it went kerthunk against a stuck valve I used mor power - backed off to get some momentum with the crank - and snapped the camshaft. Force by normal engine means is not good. You are right to use chemicals and any other thing you can think of to provide direct force rather than cranking.

 

[Soundguy]

i think he's still seeing the effects of 'stuck valve' as to why it won't open when he turns the crank.

 

[AroniaFarmer]

i think he's still seeing the effects of 'stuck valve' as to why it won't open when he turns the crank.

Yes. It is physically stuck in place. I posted some pictures of the valves.

 

[Soundguy]

you will have to get that valve moving freely before she will turn freely

 

[Gator6x4]

No I can't. moving it counterclockwise will make the flywheel stop when the valve is suppost to open. Going clock wise will just make a loud click and will keep turning.

This indicates to me the engine crankshaft will do a 360 degree turn. Something , either a broken lobe on the camshaft, a broken camshaft or a broken tappet is keeping the valve from opening. The engine will have to be opened to find out which. The valve could also be stuck, probably is what started and caused the problem.

 

[AroniaFarmer]

This indicates to me the engine crankshaft will do a 360 degree turn. Something , either a broken lobe on the camshaft, a broken camshaft or a broken tappet is keeping the valve from opening. The engine will have to be opened to find out which. The valve could also be stuck, probably is what started and caused the problem.

Thats what I am thinking. I am going to tear into the engine tomorrow and inspect everything.

 

[Soundguy]

i'm betting on stuck valves.

I had the head apart on my ford 4000 beginning of the year. intakes were stuck so bad that it bent my push rods and i had to soak the valve stems in atf and acetone and use a HAMMER and DRIVE the valves out of the guides.

yes.. stuck THAT bad. and with them stuck.. if the push rods were still in place.. she's not gonna rotate..

 

[CharlieS]

Had the same thing happen to a 15 year old briggs. stuck a valve and of course i pulled the rope through several times trying to start it. tore it down found the stuck valve AND by turning the engine afterwards, i destroyed the timing gears. you'll probably find the same thing with the wisconsin. Particularly if the timing gears are plastic such as briggs uses.
my solution was harbor freight, cheap chinese copy engine w/2 year no questions asked replacement. Price for that was the same as all the parts to repair the briggs.

 

[AroniaFarmer]

Had the same thing happen to a 15 year old briggs. stuck a valve and of course i pulled the rope through several times trying to start it. tore it down found the stuck valve AND by turning the engine afterwards, i destroyed the timing gears. you'll probably find the same thing with the wisconsin. Particularly if the timing gears are plastic such as briggs uses.
my solution was harbor freight, cheap chinese copy engine w/2 year no questions asked replacement. Price for that was the same as all the parts to repair the briggs.

We have 2 of those engines. One on a go kart and one on a water pump. They are great little engines but I am getting this one running because its just so old and cool:thumbsup:

 

[AroniaFarmer]

I think something is broken in there. When it is suppost to open the valve it just clicks and keeps turning. so maybe something is broken inside.

I still can't get the valve free, anyway