Follow the spark plug gap info on the engine or the manual

i have a 5.7 vp gi. on the ri

i have a 5.7 vp gi. on the risers there's a sticker that says .045 in the manual i downloaded from volvo is says .039. which one should i use?

"If the sticker is from VP, I

"If the sticker is from VP, I would follow its instructions. Moreover, it seems that VP has been using 0.045 in your engine model since 1995."

"looks like the sticker might

"looks like the sticker might be from gm. the owners manual says .039. the boat is a 1994. i did change the plugs a month ago. i regapped them from .039 to .045 this past weekend. the plugs do look to be full of black carbon deposits already. i was thinking it might be due to improper spark plug gap, what do you think?"

"According to Seloc, the gap w

"According to Seloc, the gap was 0.035 for your engine & year model. But to be honest, I don't know what the differences are between the two years, as both engines seem to have the same distributor and ignition coil. In any case, if 0.045 does not work for you, it makes sense to try 0.035 (or 0.039) and see if performance improves."

The black sooty deposits on th

The black sooty deposits on the plug is most likely an unfortunate effect of 'excessive idling' which happens all the time when we're boating through no wake/fuel docks/marinas/ loading ramps.

They make 'spark plug cleaners' that hook up to an air compressor. Basically it's a tiny little sand blasting bag you insert your plug into to get the soot off. I have one I use for my boat's plugs and my two stroke motor plugs.

Also...
The automotive plug used in these engines is Champion-RS12YC. That's even what comes in the tune up kit straight from factory VP... and to think I was curious as to what the difference would be with my 'marine spark plugs'. As I recall they came pre gapped @ .035-.039 and I opened them up to .045. My boat's ignition and timing seem flawless in my application.

"i opened mine up too from .03

"i opened mine up too from .039 to .045. i'm not too sure how to gauge engine performance, but to my untrained mind it seems to run better at idle to low rpm's with the .035 and the same at high rpm's with the .045. i only ran it one day for an hour or so since i regapped them so i might just need more time to get a real impression.

speaking of regapping, am i suppose to get the leading edge, middle or trailing edge of the spark plug to the respective mark on the gap tool? the spark plug seems to cover at least two or three marks when gapping them so i don't know if i should account for that when gapping"

"1st boat... this is from wiki

"1st boat... this is from wikipedia...

http://en.wikipedia.org/wiki/Spark_plug

Spark plug gap
Spark plugs are typically designed to have a spark gap which can be adjusted by the technician installing the spark plug, by the simple mechanism of bending the ground electrode slightly to bring it closer to or further from the center electrode. The somewhat common belief that plugs are properly gapped as delivered in their box from the factory is incorrect, as proved by the fact that the same plug may be specified for several different engines, requiring a different gap for each. A spark plug gap gauge with round wires of precise diameters is used to measure the gap; use of a feeler gauge with flat blades instead of round wires, as is used on distributor points or valve lash, will give erroneous results, due to the shape of spark plug electrodes. The simplest gauges are a collection of keys of various thicknesses which match the desired gaps and the gap is adjusted until the key fits snugly. With current engine technology, universally incorporating solid state ignitions and computerized fuel injection, the gaps used are much larger than in the era of carburetors and breaker point distributors, to the extent that spark plug gauges from that era are much too small for measuring the gaps of current cars.

This adjustment can be fairly critical and if it is maladjusted the engine may run badly, or not at all. A narrow gap may give too small and weak a spark to effectively ignite the fuel-air mixture, while a gap which is too wide may be too wide for a spark to fire at all. Either way, a spark which only intermittently fails to ignite the fuel-air mixture may not be noticeable directly, but will show up as a reduction in the engine's power and fuel efficiency. As the plug ages and the metal of the tip erodes, the gap will tend to widen; therefore experienced mechanics often set the gap on a set of new plugs at the engine manufacturer's minimum recommended gap rather than in the center of the specified acceptable range, to ensure longer life between plug changes. On the other hand, since a larger gap gives a "hotter" or "fatter" spark and more reliable ignition of the fuel-air mixture, and since a new plug with sharp edges on the center electrode will spark more reliably than an older, eroded plug, experienced mechanics also realize that the maximum gap specified by the engine manufacturer is the largest which will spark reliably even with old plugs and will in fact be a bit narrower than necessary to ensure sparking with new plugs; therefore, it is possible to set the plugs to an extremely wide gap for more reliable ignition in high performance applications, at the cost of having to replace and/or regap the plugs much more frequently, as soon as the tip begins to erode."

"thanks lode, i'll leave t

"thanks lode, i'll leave them like they are the. i don't mind changing them more often. they're not too expensive and not hard to get to. i can do them all in 30 minutes or less."

"I AM REBUILDING A 1977 27FT B

"I AM REBUILDING A 1977 27FT BAYLINER.I AM HAVING PROBLEMS FINDING PARTS FOR THE ENGINE A FORD 302,ie spark plugs, the engine ser# is, D1oe-6015AA 1d26, can you please tell me when this engine was built so I can find, plugs, oil filter oil pressure gage, and other outer parts that I may need. I thought this engine was a 1977 ford 302, but when I go to the parts store they give me the wrong parts.
This is a newly rebuilt engine to Marine spec. outdrive is a volvo drive."

"My old 1977 AQ240A (Ford

"My old 1977 AQ240A (Ford 351) was using Autolite 26, and the specs are the same for the 302.

Could you upload a picture of your engine, just to make sure it is what you think it is?"