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Discussion Starter #1
Forgive this description, we are new to small engines! My son took his engine apart trying to take off the governor. Then gave up and put it back together. While running, it froze up and we took it apart and saw that the push rod was bent and piece of the head was chipped where the exhaust valve goes in. So, have replaced the head, rods and a bad valve that must have been bent a little when it froze. We also went ahead and put new valve springs on along with a head gasket and valve gasket. Its starts fine, idles fine but goes very slow and cannot get up a hill. I can feel air blowing out of the sides like a bad gasket or seal. I am trying to figure out what is causing this loss of power. I used the old crankcase gasket - could that be the problem? The push rods are identical on this engine, I think? Valves are set to .003 so wondering if they should be re-adjusted. Any help is appreciated!
 

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If it were me I would retrace my steps, everything that I touched make sure is good to go. I'm sure you didn't touch the carburetor.
Reusing old gaskets or seals is something you can get away with sometimes but most of the time you should replace anyting you took off with new in the way of gaskets are seals. Could be your problem, I honestly don't know if that engine needs to have a set valve adjustment.
Stock motor that came on your coleman?
 

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Discussion Starter #5
Yep. It's a stock engine so nothing special. I assume push rods are same measurement for intake and exhaust sides? If not, then I could switch them. If I take off the valve cover, then it's a pain to keep on ordering valve cover gaskets even when it seems to be in good shape. I am worried that the crankcase gasket is bad...would that cause the poor power? If I put my hand down by the right side of the head I can feel air being pushed around but hard to tell where it is coming from. I previously thought it was a bad seal with the head gasket so replaced it and it should be fine at 17lbs but maybe there are imperfections. I am assuming that the loss of compression is causing the lack of power but wondering what else could do that? bad valve fitting? etc.
 

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Start it and run it at idle and spray some flammable brake cleaner or something around the head gasket and if the idle raises you have a leak. I really don't know if the pushrods are the same or not. The valve cover gasket if it was me I'd probably just reuse it, head gasket and crankcase I would not reuse.
 
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