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Hello, again. If no compression on either cylinder but pistons still move in and out, what does that mean? I see what looks like fresh sealant on both valve covers? What steps should I take next? Has 142 hours on it.

Remove the valve covers and make sure all the push rods in in place and while turning the engine over by hand make sure all the valves open and close the same amount.

ILENGINE said:

Remove the valve covers and make sure all the push rods in in place and while turning the engine over by hand make sure all the valves open and close the same amount.

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Will do. Thanks!

ILENGINE said:

Remove the valve covers and make sure all the push rods in in place and while turning the engine over by hand make sure all the valves open and close the same amount.

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Ok. So everything seems to be fine as far as opening and closing on both heads. At no time do the rockers ever get loose when fully open like you would find on a Briggs OHV, so Im assuming valve adjustments?

Start with valve adjustments
Usually closed up valve lash is either a mistake setting them or valve guides slipping in the head .
The latter is from overheating
All 4 valves are identical , the valve lift on the cam lobes is identical as are the rockers
So all of them should sit at the same position when their piston is at TDC compression stroke .
If not the guides are the problem.
This can be fixed if they are not too far gone

bertsmobile1 said:

Start with valve adjustments
Usually closed up valve lash is either a mistake setting them or valve guides slipping in the head .
The latter is from overheating
All 4 valves are identical , the valve lift on the cam lobes is identical as are the rockers
So all of them should sit at the same position when their piston is at TDC compression stroke .
If not the guides are the problem.
This can be fixed if they are not too far gone

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How do I find the compression stroke when there's no compression? Im not good at valve adjustment at all.

JonnyBlaze said:

How do I find the compression stroke when there's no compression? Im not good at valve adjustment at all.

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both valves will be closing or closed as the piston travels upwards.

Scrubcadet10 said:

both valves will be closing or closed as the piston travels upwards.

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Just for additional information. When you are coming up on the compression stroke and both valves are closed. Make sure the spark plugs are removed so you can see the piston or feel it with a pencil or similar, and see when it reaches its highest point and just starts back down. that is the point to adjust both valves. You want it just slightly past TDC.

Watch the valves Identify the exhaust valve and watch it when it opens the piston is coming up on the exhaust stroke as the piston reaches tdc top dead center the intake valve will open and the piston is going down on the intake stroke as the piston comes back to tdc the valve will close this is the compression stroke. Put some thing soft in the plug hole and just as the piston reaches tdc and starts back down about a 1/4 inch this where you would adjust the valves.

ILENGINE said:

Just for additional information. When you are coming up on the compression stroke and both valves are closed. Make sure the spark plugs are removed so you can see the piston or feel it with a pencil or similar, and see when it reaches its highest point and just starts back down. that is the point to adjust both valves. You want it just slightly past TDC.

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TDC on each piston, right?

JonnyBlaze said:

TDC on each piston, right?

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Correct. the pistons will have to be set individually.

Each piston, but only one side at a time .
What catches out most is the inside set screw is the locking mechanism and the outer nut is the adjustment which is backwards to what most would assume is the case

I got it running. Thanks guys! Whoever messed with it last had them cranked way down! I had to back the nut off probably 4 turns on each one.

If you have NO compression reading after quickly turning over the engine, either the Rings are totally gone or valves are not closing or you have a blown head gasket.

JonnyBlaze said:

Hello, again. If no compression on either cylinder but pistons still move in and out, what does that mean? I see what looks like fresh sealant on both valve covers? What steps should I take next? Has 142 hours on it.

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Fresh sealant on the valve covers ,could be someone installed new exhaust valves & didn't set the them. Just a guess.

I found a clue as to why I had to adjust the valves. Hmmmm....

how the heck does a head gasket end up there!?