I recently bought a 22' Starcraft with 1985 'rude 140 that runs 50:1 pre-mix. Compression is between 130-135 on all four and engine ran very well. Plugs that came in the engine were NGK BUHXW-1.
Being it was new to me I got new plugs, Evinrude plug wires, & fuel filter. The first set of plugs I got from the local auto parts and they checked their book and sold me NGK BUZ8H. On these plugs it ran ablolutely perfect until we had 25 minutes of no-wake. It then was all loaded up and wouldn't idle very well even after running it at speed for a while. Plugs had deposits on them when I took them out.
The second set of plugs I got were Champions (QL78YC) from the local marine dealer. These are listed in my owners manual as the plug for this engine. Took it out again and right from the get go it would not idle well at all. Ran fine at speed.
I then put the original NGK's back in that I cleaned up and it ran very good again, very little loading up and almost perfect idle.
There seems to be many different plugs and different charts for this engine. I think some confusion comes from that this is a 1985 which I believe when it went from "crossflow" to "looper" and the plugs changed as well. I have done a lot of reading which mostly says to go Champions but don't know 100% which plug should be in there as the recomended Champion (QL78YC) doesn't idle worth a crap.
Anyone have a sure answer?
Thanks.
Being it was new to me I got new plugs, Evinrude plug wires, & fuel filter. The first set of plugs I got from the local auto parts and they checked their book and sold me NGK BUZ8H. On these plugs it ran ablolutely perfect until we had 25 minutes of no-wake. It then was all loaded up and wouldn't idle very well even after running it at speed for a while. Plugs had deposits on them when I took them out.
The second set of plugs I got were Champions (QL78YC) from the local marine dealer. These are listed in my owners manual as the plug for this engine. Took it out again and right from the get go it would not idle well at all. Ran fine at speed.
I then put the original NGK's back in that I cleaned up and it ran very good again, very little loading up and almost perfect idle.
There seems to be many different plugs and different charts for this engine. I think some confusion comes from that this is a 1985 which I believe when it went from "crossflow" to "looper" and the plugs changed as well. I have done a lot of reading which mostly says to go Champions but don't know 100% which plug should be in there as the recomended Champion (QL78YC) doesn't idle worth a crap.
Anyone have a sure answer?
Thanks.
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