[mpeng]

Hi Folks: I have a late 48 or early 48 cub which runs and starts quickly. I did a dry compression test on it and got 40, 40, 55, 70 lbs of compression. Is this a ring job or valve job or both. Only a little bit of blue smoke on start up. Can I expect the compression to come up on a wet test?

Thanks , Mike

[Dale Shaw]

mpeng, on 23 January 2011 - 05:37 PM, said:

Hi Folks: I have a late 48 or early 48 cub which runs and starts quickly. I did a dry compression test on it and got 40, 40, 55, 70 lbs of compression. Is this a ring job or valve job or both. Only a little bit of blue smoke on start up. Can I expect the compression to come up on a wet test?

Thanks , Mike

Mike, most likely if you did a wet test (couple tablespoons of oil in each cylinder, your values would rise. Get some seafoam, follow directions putting some in the gas tank and some in the motor oil. then work the cub hard. The seafoam will help free up stuck rings, and clean up carbon deposits on the valves. You might be surprised. Also, when it starts freeing up, you should think about doing a valve lash adjustment.

Dale

[Dale Shaw]

mpeng, on 23 January 2011 - 05:37 PM, said:

Hi Folks: I have a late 48 or early 48 cub which runs and starts quickly. I did a dry compression test on it and got 40, 40, 55, 70 lbs of compression. Is this a ring job or valve job or both. Only a little bit of blue smoke on start up. Can I expect the compression to come up on a wet test?

Thanks , Mike

Yes, it should come up some.

I would suggest getting some Seafoam additive, put 3/4 in the gas, 1/4 in the oil and work your cub hard. The seafoam will help unstick any stuck rings and will also clean out any carbon deposits in the motor. This should help with your compression, and once the seafoam has worked, ou should see results and less of the blue smoke.

Dale