How tough and what tools for spark plugs in 496HO?

boxer156

Cadet
Joined
May 16, 2011
Messages
23
Might try to tackle the spark plug change myself, so I wondered about the following:

*how tough is it--not the access to the plugs, but are there any components of the engine that need to be removed during the process?

*do I need any special wrench extensions/tools?

I'm not overly mechanically-inclined, but can do almost anything with some direction--is this possible for me?
 

mkast

Lieutenant Commander
Joined
Nov 6, 2002
Messages
1,934
Re: How tough and what tools for spark plugs in 496HO?

When was the last time the engine was serviced?
 

wifisher

Chief Petty Officer
Joined
Mar 9, 2011
Messages
578
Re: How tough and what tools for spark plugs in 496HO?

You need a spark plug socket. Not really much to it. Unplug the wire, remove old plug and install new. Reconnect wire. Be sure the wires do not get reconnected to the wrong plug.
 

45Auto

Commander
Joined
May 31, 2002
Messages
2,842
Re: How tough and what tools for spark plugs in 496HO?

You'll need the usual sockets, extensions, and flex-couplings. It's pretty busy on the port side with a lot of cooling hoses in the area. Make sure you use equivelent iridium plugs when you replace them. The factory plugs on my 2003 496HO lasted until 2009 when it developed a tiny miss under acceleration, and I'm hoping the new ones last just as long! If I remember correctly, the port rear plug was the only one that was difficult to get to. Seems like I had to remove one of the cooler hoses to be able to reach the plug. Or maybe it was unbolt the oil cooler or power steering cooler to let it move out of the way. Anyhow, it's no big deal.
 

frozen lake

Recruit
Joined
May 10, 2009
Messages
3
Re: How tough and what tools for spark plugs in 496HO?

I always use a socket, 5/8 deep, a 3/8 drive and a few extensions.

Depending on how much space there is I may need an extension. Removing the boots is easier if the engine is warm but be carefull that you don't get it too hot and burn yourself.

There are spark plug wire pliers which are helpfull getting the boots off. trist and pull making sure not to rip the boots. Once the plug is loose a short piece of rubber fuel hose pushed over the top of the plug will make it easier to unscrew the plug. The fuel hose also helps start the new plug in the threads on the head.
You already checked the plug gap to the engine mfgs specs with the plug gap tool from an autoparts store right?
Install the plugs and I always do them one at a time so I don't get the firing order mixed up or if the weather turns perfect I can go boating an any time.
Use a small bit of dielectric greese on the tip of the plug to ease boot instalation and seal from moisture entering.

The plug wires should be replaced if the are stiff, look burned or cracked. again one at a time and free from touching the exhaust manifolds or anything that can chafe through the insulation.

Once you do a this a few times it becomes very easy.
 

boxer156

Cadet
Joined
May 16, 2011
Messages
23
Re: How tough and what tools for spark plugs in 496HO?

Thanks for the help!! Sounds like something I can tackle myself. Does an AutoZone/Advance stock the plugs, or am I better just getting them from the marina?
 

45Auto

Commander
Joined
May 31, 2002
Messages
2,842
Re: How tough and what tools for spark plugs in 496HO?

Get the plug brand and number and do a search for them on the Internet. You'll find them for $5-$6 each at an automotive place. They aren't "special marine" plugs, just fancy (iridium if i remember right) automotive plugs. The same plug will be over $20 each from a marina or marine supply.
 

muc

"Retired" Association of Marine Technicians...
Joined
Jul 7, 2004
Messages
2,170
Re: How tough and what tools for spark plugs in 496HO?

Be careful of the plug wires. Merc list price is over $575.00 for the set.
Or $112.50 each.
 
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