Duke
SILVER Star
I've been contemplating having my head done on my '40 as I've been having a puff of smoke on hot starts and it smokes for about 20 seconds after idling for more than 5 minutes.
So, I redid my compression test from a few months ago as the tester line was cracked and old (friends). Bought my own and went to work this morning on it.
Results are as follows:
Cyl Dry Wet
1 149 150
2 148 150
3 150 152
4 145 145
5 145 145
6 155 155
Looks good and I'm assuming that my pistons/rings are doing their job.
My concerns are the appearance of my spark plugs. They have about 3000 miles on them and my feeling is that it's running lean and cold? The first photo (taken with my iphone so sorry for the quality) is of all six in order. The second shows cylinder 1 on the left and 2 on the right, the other four have the same appearance. I would appreciate some feedback from the many experts here on the forum along with some suggestions.
I did a rebuild on the carburetor about 3k miles ago. Pulled it completely apart and soaked it in carb dip. I purchased a Keyster kit and re-assembled in the order it was take apart. It's run wonderfully since then. I did take it in to a guy with a dyno shop in Tacoma, WA (Bill's) and he "tuned" the carb for me based on the dyno/emmisions reading. I'm not an expert in the terminology so forgive me if I have something wrong in my vernacular. I'm learning.
The dyno guy said it was running lean and I needed to get a larger primary jet. So, I pullled off the top of the carb, pulled the primary and it was (hard to read) a 121 or 124. I replaced it with a 144 and noticed an increase in responsiveness immediately. Went back to have it retuned and was told "it was better, but still was running lean". We left it at that and I drove it thru the fall and Christmas daily.
I am running Penn 20-50W oil in it and have been changing it every 1000 miles since I purchased the vehicle. It had been sitting for 12 years prior to me purchasing it and I believe it was driven hard by the PO in preparation to sell it. As such my feeling is that the valve guides were damaged as they were not using a high zinc oil in it prior to parking it, nor did they change the oil prior to starting it up and selling it to me.
I am changing the oil again today and can say that it now has very little discoloration. It is getting progressively cleaner and will probably drive it 1500 to 2000 miles on this oil change.
Lastly, I run 92 octane fuel in it. My timing is set right at the BB and I adjusted the valves per OEM spec when I first got it. Runs like a Singer Sewing Machine. I am pulling a consistent 19" of vacuum at 660 rpm idle. I've replaced the plugs and gapped them to .033 inch.
Thanks to all and I look forward to your counsel
best.....
Ken
So, I redid my compression test from a few months ago as the tester line was cracked and old (friends). Bought my own and went to work this morning on it.
Results are as follows:
Cyl Dry Wet
1 149 150
2 148 150
3 150 152
4 145 145
5 145 145
6 155 155
Looks good and I'm assuming that my pistons/rings are doing their job.
My concerns are the appearance of my spark plugs. They have about 3000 miles on them and my feeling is that it's running lean and cold? The first photo (taken with my iphone so sorry for the quality) is of all six in order. The second shows cylinder 1 on the left and 2 on the right, the other four have the same appearance. I would appreciate some feedback from the many experts here on the forum along with some suggestions.
I did a rebuild on the carburetor about 3k miles ago. Pulled it completely apart and soaked it in carb dip. I purchased a Keyster kit and re-assembled in the order it was take apart. It's run wonderfully since then. I did take it in to a guy with a dyno shop in Tacoma, WA (Bill's) and he "tuned" the carb for me based on the dyno/emmisions reading. I'm not an expert in the terminology so forgive me if I have something wrong in my vernacular. I'm learning.
The dyno guy said it was running lean and I needed to get a larger primary jet. So, I pullled off the top of the carb, pulled the primary and it was (hard to read) a 121 or 124. I replaced it with a 144 and noticed an increase in responsiveness immediately. Went back to have it retuned and was told "it was better, but still was running lean". We left it at that and I drove it thru the fall and Christmas daily.
I am running Penn 20-50W oil in it and have been changing it every 1000 miles since I purchased the vehicle. It had been sitting for 12 years prior to me purchasing it and I believe it was driven hard by the PO in preparation to sell it. As such my feeling is that the valve guides were damaged as they were not using a high zinc oil in it prior to parking it, nor did they change the oil prior to starting it up and selling it to me.
I am changing the oil again today and can say that it now has very little discoloration. It is getting progressively cleaner and will probably drive it 1500 to 2000 miles on this oil change.
Lastly, I run 92 octane fuel in it. My timing is set right at the BB and I adjusted the valves per OEM spec when I first got it. Runs like a Singer Sewing Machine. I am pulling a consistent 19" of vacuum at 660 rpm idle. I've replaced the plugs and gapped them to .033 inch.
Thanks to all and I look forward to your counsel
best.....
Ken
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