knock, knock, knocking

[bigcity]

I have a briggs 5hp cast iron bore, It knocks bad at wide open throtel otherwise runs good

 

[Strigoi]

that's good to know.

 

[Motra]

that's good to know.

LOL! I don't even use goofy little terms like LOL but that made me LOL.

 

[Strigoi]

LOL! I don't even use goofy little terms like LOL but that made me LOL.

it's not phrased as a question, so i'm guessing that he's just letting us know that it knocks.

i was hoping for a knock knock joke when i read the title.

 

[bigcity]

knock

Im glad you guys enjoyed that. At the time I had a house full of screaming kids and a nagging wife, about the motor Is it a major problem. will it likely need a rebuild or a simple fix ???????????:

 

[Motra]

Sorry about that! Didn't mean to turn your question into playtime here and I understand your situation. When you say "wide open throttle," is that with the governor operating (3600 RPM) or is your engine ungoverned? If there is excess wear on the connecting rod you'll hear knocking when the engine is under a load. You can hold the brake and give it throttle at the same time to really load the engine. It could also be piston slap, that makes a knocking sound. If you're running it at much higher RPM than the engine is designed for you could be getting valve float.

 

[Strigoi]

if it's knocking that's not good and you're most likely going to have to tear the motor apart.

i doubt it's piston slap. my old Z28 had that (damn early LS1 motors) and it didn't sound like a knock.

 

[bigcity]

Thank you for the info. and i believe the motor is not governed. I'll start there

 

[waynelass]

possibility

could be floating the valves , if there is no govener.

 

[mnibike]

maybe the rod is slowly bending and going to brake

 

[65ShelbyClone]

If it's actually knocking, then it's probably a worn out rod. Nothing to do but replace it before it takes the whole engine out. It can be done without removing the piston, but probably not a good idea for a first timer.

 

[blownengine]

Change the rod without removing the piston you say? How is that possible?

 

[65ShelbyClone]

Take the crank out and then slide the piston down far enough to remove the pin circlip. Find a way to hook the back of the pin and pull it out. The hard part is doing all that while not spinning the piston in the bore.

 

[briggs_boy]

Take the crank out and then slide the piston down far enough to remove the pin circlip. Find a way to hook the back of the pin and pull it out. The hard part is doing all that while not spinning the piston in the bore.

shit its easier to just take the head off and take the damn piston out.:thumbsup:

 

[~JM~]

I have a briggs 5hp cast iron bore, It knocks bad at wide open throtel otherwise runs good

That's easy... Stop holding the throttle wide open. :doah: Problem solved.

 

[blownengine]

shit its easier to just take the head off and take the damn piston out.:thumbsup:

Thats what i was thinking. Its more work to take out the flywheel and crank

 

[65ShelbyClone]

I didn't say anything about it being easier or more worthwhile. It's just an option if you desperately want to avoid news rings and honing.

 

[fordman50]

Its a bad rod berring. Welcome to B&S crap I'm sorry to say. B&S is pure :001_9898:

 

[jimh]

They don't have bearings. The rod clamps on the crank. Lack of lubrication will cause ANY engine to fail. I have Briggs and Tecumsehs 40 years old, still running, not knocking.:thumbsup: Low oil levels and lack of oil changes are usually the culprit.

 

[GTO]

Is it a "tapping" or "knocking"? Could be the valve springs are worn or light.