Are Boat spark plugs the same as Automotive?

Pomoxis · #1 (**permalink**) 10-18-2009, 10:22 AM

I'm about to buy my winterizing stuff. So far my list is:
OMC 3.0 I/O

1. spark plugs - kind? I can get the specs from my book.
2. fogging oil
3. Lower unit oil
4. motor oil - not sure on weight..thinking 10w/30???
5. gelcoat repair - minor stuff around the boat..
6. some kind of paint for my motor...not sure if there's a special kind..
7. correct size screwdriver for my I/O plugs (large and about 3mm thick).

The rest of the work is just cleanup stuff..boat soap/wax, carpet..etc.

Fishtaco · #2 (**permalink**) 10-18-2009, 09:01 PM

Johnson/Evinrude/OMC make some very nice products for their engines, such as fogging oil, and their quality is quite good. I've always liked their stuff.

As for that screw driver, I like a big craftsman brand with the red, blue and clear handle and a square shank. This allows you to put the screwdriver in the slot and hold it tightly into the slot with one hand, while using a crescent wrench on the square shank to turn with in the other hand. Makes breaking those things free easy and drama free.

As for the oil, follow the manufacturer's recommendation. We used to use a 5W50 for the smaller OMC I/O's years ago. I have no idea what they recommend now.

Be sure to change the lower unit oil as part of your winterization routine. A small amount of water (emulsification in the oil) is normal or acceptable, but if there is too much, it can freeze and bust the lower unit.

Plugs... yes and no. For a given engine size, the gap may be the same, but the heat range will be different. And the nose length may differ as well. Just get what is recommended and you can't go wrong.

Shellback · #3 (**permalink**) 10-19-2009, 07:06 AM

A few suggestions for the lower unit screws. Make sure your screwdriver blade fills the slot, don't make due with one that is a sloppy fit. Those buggers can get real tight, and a sloppy fitting screwdriver is sure to bugger up the slot. If the correct screwdriver doesn't want to budge the screw, go to Sears hardware and buy a small hand impact driver with the proper bit. A moderate tap should free the screw. Don't wind up and really slam it, as the case is only aluminum. Also when servicing your outdrive, remove the prop and make sure there's no fishing line behind it. Fishing line will cut the seals over a period of time. When reinstalling the prop, lubricate the splines well with grease.
If you are draining your block and manifolds by removing the plugs, it doesn't hurt to use a piece of coathanger wire to probe inside the hole, making sure no rust scale or other debris could be blocking the flow of the drain water.