Want to change spark plugs - 92 7.4L King Cobra

07caddy

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Jun 9, 2010
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Would like to change the spark plugs in my boat. Have no idea when the PO changed them and the boat is idling rough and dying at low speeds upon acceleration (like around the ramp and dock) -- requires multiple starts.

Question:

Do I have to remove the manifold to get at the plugs?
 

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HT32BSX115

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Re: Want to change spark plugs - 92 7.4L King Cobra

Would like to change the spark plugs in my boat. Have no idea when the PO changed them and the boat is idling rough and dying at low speeds upon acceleration (like around the ramp and dock) -- requires multiple starts.

Question:

Do I have to remove the manifold to get at the plugs?


That's going to be your call really..........

If you cannot get to them with manifolds on, then you would have to pull them..... A LOT of boat manufacturers don't think about maintenance when they install engines.....
 

Bondo

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Re: Want to change spark plugs - 92 7.4L King Cobra

Question:

Do I have to remove the manifold to get at the plugs?

Ayuh,... Or maybe the whole Motor...

Yer picture is too close up to see...
 

bruceb58

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Re: Want to change spark plugs - 92 7.4L King Cobra

The manifolds will not be in the way...can't say the same for your boat!

I know because I have the exact manifolds on my Volvo 7.4L.
 

07caddy

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Re: Want to change spark plugs - 92 7.4L King Cobra

Pics from a different distance and/or angle. At this point I don't see how it's possible to get the plugs out (with the exception of the two rear plugs) without reaching under the manifolds. Reaching reaching under the manifolds doesn't seem feasible because there's less than 2" of room between manifold and decking. Removing the decking seems a little over the top to change out plugs.

And I was looking at the manifolds and it looks almost impossible to take the out, given the location of the bolts....
 

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RIDEPATE

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Re: Want to change spark plugs - 92 7.4L King Cobra

LOL, I almost asked "Is that a Four-Winns??" until I saw your sig. My little Horizons motor is up much higher than yours, my decking is about plug-high. That's gonna be tough.
 

07caddy

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Re: Want to change spark plugs - 92 7.4L King Cobra

LOL, I almost asked "Is that a Four-Winns??" until I saw your sig. My little Horizons motor is up much higher than yours, my decking is about plug-high. That's gonna be tough.

Yeah, some brainwave engineer decided that changing plugs required removal of multiple components (e.g., manifold, risers). Actually, I seriously doubt I could get the manifolds out since those bolts are below the decking and there's no room to get down there.

Is a 350 motor significantly smaller in size than a 454? I'm ready to rip this stuff out and start over.
 

Bondo

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Re: Want to change spark plugs - 92 7.4L King Cobra

Is a 350 motor significantly smaller in size than a 454? I'm ready to rip this stuff out and start over.

Nope,... Not really... Fully dressed, they're nearly the same....

You thought I was kiddin' in post #3,..??
 

HT32BSX115

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Re: Want to change spark plugs - 92 7.4L King Cobra

Yeah, some brainwave engineer decided that changing plugs required removal of multiple components (e.g., manifold, risers). Actually, I seriously doubt I could get the manifolds out since those bolts are below the decking and there's no room to get down there.

Is a 350 motor significantly smaller in size than a 454? I'm ready to rip this stuff out and start over.

Yeah........and it looks like you have the Wonderful Spitfire ignition too.......:facepalm:
 

07caddy

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Re: Want to change spark plugs - 92 7.4L King Cobra

Bond-o, I thought you were kidding, but reaching the plugs any other way is going to be a challenge. I read somewhere that an individual used a craftsman swivel socket....

Rick, Yeah, my engine/drive combo is equipped with tons of cutting edge technological/electrical features. :mad::mad:
 

Lou C

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Re: Want to change spark plugs - 92 7.4L King Cobra

winterize 015.jpgI wish I could offer a suggestion to make it easier, seriously you gotta wonder what some of the boat designers were thinking of when they design things, if you put the engine down below deck level, then leave a foot and a half around the engine to get at stuff...my old 88 Horizon 200 is not bad, when you remove the rear seats and bulkheads its pretty open....I can change a starter in about a half hr and changed manifolds in about an hr per side.....
 

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CobiaXL

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Re: Want to change spark plugs - 92 7.4L King Cobra

Get the sawzall out... :)
 

07caddy

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Re: Want to change spark plugs - 92 7.4L King Cobra

I'm thinking about it. If I could just cut out an inch or so on each side, I may be able to get in there and change a friggin spark plug :D
 

bruceb58

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Re: Want to change spark plugs - 92 7.4L King Cobra

You very likely can remove the housing. On my boat I can do that and need to do that for certain tasks like changing the starter.
 

07caddy

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Re: Want to change spark plugs - 92 7.4L King Cobra

I do have fairly long panel in the floor right in front of the engine. Thinking about removing it to see if it allows some type of access to the engine.
 
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