RunningRed
Well-known member
Plus I could hear air blowing past the pistons on all of them but the engine was cold so that could have been why.
Farmall Cub Low Idle Pop- Video Added!!!
- Thread starter RunningRed
- Start date
The valves with the bigger heads are the intake valves, the valves with the smaller heads are the exhaust valves.
I can't tell what your picture in post 20 is.
Below is a picture from TM Tractor Parts of a Cub engine block, you can see where the valves go in it.
The engine could have a burned valve, or burned valve seat, just possibilities.
I can't tell what your picture in post 20 is.
Below is a picture from TM Tractor Parts of a Cub engine block, you can see where the valves go in it.
The engine could have a burned valve, or burned valve seat, just possibilities.
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RunningRed
Well-known member
Glen in my post 20, that's a picture of the intake valve when it's open. They all look like there build up with carbon but the 1# cylinder intake valve is the worst. The valves themselves look good and so do the seats from what I can see on my inspection camera. Ofcourse that doesn't mean there isn't a bad spot where I can't see it.
RunningRed
Well-known member
You don't show much of the exhaust pipe, most of the video is the door, I guess.
It would be nice to know how the engine sounds when you hold the exhaust cap fully open with your hand, so we don't hear the clicking of the cap.
If the engine is hot, wear gloves so you don't burn your hands.
It would be nice to know how the engine sounds when you hold the exhaust cap fully open with your hand, so we don't hear the clicking of the cap.
If the engine is hot, wear gloves so you don't burn your hands.
RunningRed
Well-known member
Glen, the first part of the video was showing the cap moving. When you see the door IS when I had the cap open with my hand and I had the speaker of my phone up at the exhaust so you can hear it. The speaker on my phone isn't the best and I wanted to make sure the sound was heard. If you hear a static noise it's probably my speaker, but you can hear the thud or popping noise I was referring too.
RunningRed
Well-known member
I have a leak down tester ordered. I ran a whole can of seafoam areasol engine cleaner through it. That helped clean the valve seats but did little for anything else. The valves are all making a tapping noise now instead of just one. Tomorrow I am going to pull the valve cover off and check my lash again. I went through the carburetor today and cleaned it and set the float height, still made no difference. I am running Autolight 388 spark plugs so I don't know if that could be contributing some being they are a resistor plug.
It is common for the Cub valves to make tapping sounds, they don't have hydraulic lifters.
There could be a misfiring spark plug making the popping sound in the exhaust, rare I would think, but possible.
The man I have known for years at the Case IH dealer I shop at has said don't put resistor spark plugs or spark plug wires on a Cub. He said the system wasn't engineered for them.
The resistor parts cause problems with the points. If you use the Cub lots, it can make material move from 1 point to the other. The ones I have seen it makes a point on 1 point, and a hole in the other point. The set of points is pretty much ruined.
RunningRed
Well-known member
Thanks Glen. I have copper core wires, I may switch to a non resistor type plug.