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DonziDave
04-25-2006, 08:03 PM
Is the plug gap based on the plug brand or the engine type? I have always used NGK plugs, but the store was out of stock, so I cross referenced and bought Autolite plugs. The NGK gap is .035 and the Autolite calls for a .045 gap. A gap of .045 just seems large to me. I change plugs every season even though they are in perfect condition. Engine is a 5.7L 350 SBC. All opinions welcome....!!!

Dave

MOP
04-26-2006, 06:41 AM
What ignition are you running? My stock IV Merc coil ran very good at .040, some run .035. I run at .060 with 60,000 volt hi perf coil.

DonziDave
04-26-2006, 07:50 PM
Thanks for the reply MOP.
Boat is a stock '86 18C, so I assume the electronic ignition is the Merc T-Bolt IV...??? Yes/No...?? Should I stick with the plug mfg. gap or what do you recommend?
Thanks - Dave :confused:

DonziJon
04-27-2006, 04:54 PM
Dave: First off, I don't know why anyone would change spark plugs every season. Spark plugs manufactured today are good for TENS of thousands of miles in an automobile. Your boat engine is no different. How many thousand miles do you drive your boat every year? Does the motor start up quickly? Does it idle smoothly once it's warm? If it ain't broke..don't replace it.

I put new plugs in my Minx when I first got it. (used) That was almost ten years ago. The boat still fires up right away and runs fine. Those plugs are still working. If you want to knock yourself out, pull the plugs out every season, have a look at them, and if they look good, put them back in and have a beer. JOHN :bonk:

BUIZILLA
04-27-2006, 06:04 PM
If you want to knock yourself out, pull the plugs out every season, have a look at them, and if they look good, put them back in and have a beer. JOHN :bonk:that's kinda like taking your 10 year old dirty socks off at the end of the day, and putting them back on in the morning, and wearing them 10 more years...

:wink:

DonziJon
04-27-2006, 06:49 PM
that's kinda like taking your 10 year old dirty socks off at the end of the day, and putting them back on in the morning, and wearing them 10 more years...
:wink:

If that works for you....go for it. I guess the problem here is I'm not in the buisness of selling spark plugs. By the way: MY socks don't stink: John :wink:

BUIZILLA
04-27-2006, 07:58 PM
If that works for you....go for it. I guess the problem here is I'm not in the buisness of selling spark plugs. By the way: MY socks don't stink: John :wink:after 10 years, everybody's socks stink....

MOP
04-27-2006, 08:47 PM
Most all dealerships will change plugs & points if equipped every season, on some boats they were near new and may have run just fine for awhile longer. Some feel it is unnecessary, if you look at it as insurance that you have parts that should give you good service throughout the new season then your mind set changes. Our hobby is an expensive one to say the least plugs are barely spit in the bucket, also by pulling them and seeing the condition of each cylinder you can get an idea if anything is not right. With the loads that marine engines run under reading the plugs at least once a season to me is a must, many of us read the plugs any time we think something is not right also when ever we fiddle with the carb or timing. Different stroke for different folks, I like not being towed!

Phil

DonziDave
04-27-2006, 09:21 PM
Thanks to all for the input...!!!

I don't put extreme hours on the boat each season. But I do replace pefectly good plugs each year, change oil that is still transparent twice a season, change the pretty green lower unit oil, change oil filters, gas filters, pump clean grease out of the fittings with new clean grease. I pump out the remaining gas in the tank at season end rather than use stabilizer.

I guess I am just throwing my money away....!!! But as MOP said..."It's barely a spit in the bucket". The boat is 20 years old this year, runs a good as the day I bought it, and the only money spent on repair has been to rebuild the carb. and replace the AreoQuip fuel line. So money spent on over-maintainence has been cheap dollars.

Hey MOP - Take a shot at my "Alternator" post.

Dave