The oil passage in those engine is big enough for the push rod to fall into the crankcase. The valves are lubed by splash/vapor so there isn't a lot of oil movement into the head area.
Briggs Intek 25HP with bent intake push-rod; WHY?
- Thread starter grassy
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Fish
Lawn Pro
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After installing the new pushrod and adjustments, leave the valve covers off and the plugs out, and turn the engine over by hand a few times while you watch things....
Deere parts guy says they see the intake rod bend a lot. A sacrificial part when anything is out of whack. After putting the new rod in I found the lash to be way too tight. There was no clearance at all. That could be what bent it... hopefully...
Almost ready to try to fire it up. Without thinking I had removed the carb before doing a compression test so I have to get it back on before I can test. I really need new fuel lines too. What are they 1/4"? I have some 1/4" Tygon but it's too thin wall for the clamps. So much to do
Almost ready to try to fire it up. Without thinking I had removed the carb before doing a compression test so I have to get it back on before I can test. I really need new fuel lines too. What are they 1/4"? I have some 1/4" Tygon but it's too thin wall for the clamps. So much to do
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Take a piece of The fuel line to a parts store, they should have it!
Well it fired right up. Only thing is, at idle it's knocking like crazy. I can't remember if it did that before or not. At high/running RPM I can't tell if it's knocking or not.
I have no idea why anything I did would make it knock, maybe it always did this. At low RPM it's so bad that it sounds like a diesel.
Listen:
https://vocaroo.com/i/s1NW2WkVMRqE
I have no idea why anything I did would make it knock, maybe it always did this. At low RPM it's so bad that it sounds like a diesel.
Listen:
https://vocaroo.com/i/s1NW2WkVMRqE
bertsmobile1
Lawn Royalty
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Thick oil is one of the signs of overheating
We seem to be going in circles but always end up at the same point.
If it is a pre-ignition knock then both the pressure and temperature will skyrocket thus causing the valves to stick
If it is a loose rod knock then the piston could be hitting the valve.
If it was sitting in the shop in front of me I would be pulling the plugs and placing a rod on top of the piston.
Then with gentle down force on the rod rotate the engine several revolutions feeling for a click when the piston broaches TDC which indicates a loose rod.
I do this because I am adverse to supplying customers new engines out of my pocket.
I feel there is a lot more to this story than we have been told and you have been sold a mower with a hand grenade masquerading as an engine.
After doing some mowing I think the knock was always there (at least since I have owned it). So for the last 5 years or so has been working OK for me.
There is no question this mower has been severely abused. Oil never changed, belts routed all wrong, bad blades, bad wheels, bent crankshaft, and all manner of problems. I took it on as a cheap mower and never expected it to last this long. Now it's kind of a friend that I try to keep going.
I wish I hadn't taken the carb off because now it seems to have an air leak or something. Getting some minor backfire/stuttering. Ah well... Damn.
There is no question this mower has been severely abused. Oil never changed, belts routed all wrong, bad blades, bad wheels, bent crankshaft, and all manner of problems. I took it on as a cheap mower and never expected it to last this long. Now it's kind of a friend that I try to keep going.
I wish I hadn't taken the carb off because now it seems to have an air leak or something. Getting some minor backfire/stuttering. Ah well... Damn.