How in the heck do you get these spark plugs out??

hogluvr

Seaman
Joined
Dec 1, 2013
Messages
72
1992 Four Winns with 5.0 HO OMC Cobra, new-to-me boat, first-timer and want to tune it up. Went to R&R the plugs and couldn't do anything more than get a socket on the plug, no way to get a ratchet, extension, swivel or even a wrench on the flats of the socket? Please don't tell me I have to pull the exhaust manifolds/water jackets just to change plugs?!?
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
13,024
On some of the Ford engines the manifolds do get in the way of plug removal, you may need to use a swivel ratcheting box wrench or similar. The plugs in my Chevy 4.3 V6 with either the OE OMC manifolds or the aftermarket Barr manifolds were always very easy to remove.
 

gm280

Supreme Mariner
Joined
Jun 26, 2011
Messages
14,605
Seems the design engineers have no idea what the actual technicians have to do to change such things. You would think in todays modern technology they would at least talk between themselves when designing anything. But that phrase; "The left hand doesn't know what the right hand is doing", sure holds true...
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
13,024
In a case like this where the manifolds overhang the plugs maybe a crowfoot wrench would work
 

hogluvr

Seaman
Joined
Dec 1, 2013
Messages
72
Thanks for the replies guys. I ordered a 1-piece swivel plug remover which MAY work, the crowfoot idea is a good one too. The problem seems to be the length of the socket, there's no room on the end to get anything in there. I applied for a job once (I'm a mechanical designer) and they told me that once an engineer designed a new product they had to go down to the shop and build the first one themselves! I'll bet if everyone had this mindset it would eliminate a lot of this type of thing!
 

Horigan

Senior Chief Petty Officer
Joined
Jun 12, 2016
Messages
686
You should be okay once you get the plug socket with the integral swivel. There isn't room to pull the plugs with a separate swivel on these engines, as you're finding out.
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
13,024
It sounds like OMC contracted with a company to cast these manifolds and then no one thought to see if they could get a socket on the spark plug!
I noticed that the original design of the 2 piece OMC manifolds for the V6s was changed to give more clearance, the first few years they made them it looks like they might have had the same problem
 
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