18HP Intek Knock From Rod?

[darrinster]

It's obvious the engine has a knock. Is it always the rod making the knocking sound? Or can the counter weight make this noise? I've uploaded some videos.

Engine spinning freely https://youtu.be/DWNHS7U3hq4

Engine running https://youtu.be/nifPUbBlrYw

Engine running overhead view https://youtu.be/txRhIZTGGfU

 

[Fish]

Also could be a buildup of carbon in the combustion chamber. And the piston is hitting some carbon.

 

[darrinster]

Also could be a buildup of carbon in the combustion chamber. And the piston is hitting some carbon.

When I turn the engine by hand back and forth you can hear a clatter noise. Though on another newer intek with way less hours I don't hear that noise.

Also the knocking intek is puffing out some black smoke and the spark plug had oil on it. Bad rings?

Are these engine's worth rebuilding to sell?

 

[Fish]

Indicates it could be a blown head gasket,
Pull the head and look.

If it has a large buildup of carbon, scrape it off, and put it back together and start it with the old gasket for just a little. See if it gets any quieter.

Pulling the head is not hard to do.

 

[darrinster]

Indicates it could be a blown head gasket,
Pull the head and look.

If it has a large buildup of carbon, scrape it off, and put it back together and start it with the old gasket for just a little. See if it gets any quieter.

Pulling the head is not hard to do.

Yea I've replaced lots of head gaskets on these. Just seems like I'm getting more inteks lately that are knocking. I assume it's the rod needing replaced?

 

[Fish]

It could be that all of the oil from the bad head gasket has cooked a bunch of carbon, taking the head off can tell you. If after you pull the head off, you can check for a bad rod, and give you a better idea what you are looking at.

 

[Tinkerer200]

Yea I've replaced lots of head gaskets on these. Just seems like I'm getting more inteks lately that are knocking. I assume it's the rod needing replaced?

In my experience a knock in these engines is most likely the counter balance system. Apparently as a mechanic you should know to post the engine model number. IF this is a 31 series, note that they made a drastic change in counter balance and sump in later models. IF it is the counter balance then no, not practical to rebuild.

Walt Conner

 

[darrinster]

In my experience a knock in these engines is most likely the counter balance system. Apparently as a mechanic you should know to post the engine model number. IF this is a 31 series, note that they made a drastic change in counter balance and sump in later models. IF it is the counter balance then no, not practical to rebuild.

Walt Conner

Yea it's a 31 series. I had the head off and pushed on the piston but didn't feel any play. So I assume it's the counter balance. I've acquired quite a few knocking engines this year. I've been swapping over older briggs and kohler commands.

I wonder if Briggs will bring out a new single engine anytime soon?