I ran into a problem the other day and was wondering if anyone had any thoughts on what happened to me.
I have a 1988 125 Force. I've done quite a bit of work to get it mechanically sound. Compression 150 LBS+ on all 4 cylinders, fuel pump and carbs all re-done. Runs great..... until yesterday. I have been using NGK BUHX plugs. I looked at some posts and saw that some folks have been using NGK BUHW in their 1988 125's with better results. I have the Prestolite ignition with the blue coils and CD units. I noticed that the gap between the center electrode and the body of these surface gap plugs on the BUHWs were slightly wider that the BUHXs. Gap on the BUHXs were about .025 and BUHWs were about .035. Anyways, I installed the BUHWs and ran fine for about half an hour, then started to miss. I figured that this didn't work. I put the BUHXs back in and I could hardly get on plane. Bottom line was number two cylinder stopped firing. It looks like it's the CD unit. Coil checks out fine.
Here is my question. Is it possible that by using the BUHW plugs, I could have caused the CD unit to fail?
One additional thing that I noticed was that the BUHX plugs read high resistance ( mega ohms) when I ohm out the plugs from the center electrode to the tip where the plug wire is attached. The BUHW plugs read less than .5 ohm resistance.
Any thoughts?
I have a 1988 125 Force. I've done quite a bit of work to get it mechanically sound. Compression 150 LBS+ on all 4 cylinders, fuel pump and carbs all re-done. Runs great..... until yesterday. I have been using NGK BUHX plugs. I looked at some posts and saw that some folks have been using NGK BUHW in their 1988 125's with better results. I have the Prestolite ignition with the blue coils and CD units. I noticed that the gap between the center electrode and the body of these surface gap plugs on the BUHWs were slightly wider that the BUHXs. Gap on the BUHXs were about .025 and BUHWs were about .035. Anyways, I installed the BUHWs and ran fine for about half an hour, then started to miss. I figured that this didn't work. I put the BUHXs back in and I could hardly get on plane. Bottom line was number two cylinder stopped firing. It looks like it's the CD unit. Coil checks out fine.
Here is my question. Is it possible that by using the BUHW plugs, I could have caused the CD unit to fail?
One additional thing that I noticed was that the BUHX plugs read high resistance ( mega ohms) when I ohm out the plugs from the center electrode to the tip where the plug wire is attached. The BUHW plugs read less than .5 ohm resistance.
Any thoughts?
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