Just did a leak down test and there were NO noticeable leaks! I did notice the exhaust valve gap was a little loose. Decided to roll over the engine and check both gaps. To my surprise the exhaust valve had about 1/4" travel HOWEVER the intake valve had almost NO travel. I tried to measure with a ruler and it looked like 1/16" travel at most. I guess it's time to split the case and look at that after market cam I put in late last summer. Seems really odd to have trouble with a lobe??
After looking at some bad camshaft reviews on Amazon, it seems several people had worn lobes after anywhere from 20 hours to a couple years. I just ordered the OEM camshaft. I don't go cheap on replacement car parts, guess the lawn mower is no different...live and learn.
Alan46
Active Member
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Good luck!
What is the symptom indicating low power? Speed decreasing? Blades turning slowly? If speed is the indicator, the trans itself could be the problem, especially if it's a hydro.
ILENGINE
Lawn Royalty
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Had one in the shop several years ago that had worn the intake lobe almost round so the valve was only open for a short period of time. Symptoms were the throttle butterfly was being pulled to the full open position by the governor spring but the engine would only run 2400 rpm.
grumpyunk
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Before reading of the altered valve lift, I was going to suggest checking the governor linkage to see that it was attempting to provide full throttle when the load increased. I would also compare valve stem height on both valves and the rocker arm mount to be sure it had not started to move out of the cylinder head.
tom
tom
I will check valve/rockers when I put it back together.
Got the OEM camshaft. Looks like an upgrade and came with new tappets. Too bad the crankcase gasket has been delayed a few days. Guess I will just hang out watching the grass grow.
Got the OEM camshaft. Looks like an upgrade and came with new tappets. Too bad the crankcase gasket has been delayed a few days. Guess I will just hang out watching the grass grow.
Back together and running at full power. Mowed pretty high grass with ease. After market cam intake lobe was worn off to almost round. Found some silver sludge in the bottom of the crankcase from the lobe. Fresh oil and filter and all seems well. I did put the OEM carb back on.