'93 OMC 5.0L HO (Ford) Spark Plug change process question

[Jono69]

I just purchased a 1993 Sunbird Regency 195 with a OMC 5.0 HO (Ford) motor with an OMC Cobra outdrive. It has sat in storage for a number of years and I am currently running through the engine to get it back into action for the upcoming season (it is running!!). I am wanting to do a compression check and change the spark plugs on this beast and am having a hard time figuring out how to get to them. The only reachable plugs are #1 and #5. All of the others are obstructed by the exhaust manifolds. Is there a way to change all of the plugs without completely removing the exhaust manifolds and all of the other mechanicals attached to them?? I can't seem to find much info on this process on here or anywhere and the MX manual doesn't provide any guidance. Does anyone have any experience with this or know any tricks?? I have tried using a universal joint and spark plug socket (3/8'') with no luck.
Thank you in advance for any guidance you guys can provide!

 

[perna00]

Re: '93 OMC 5.0L HO (Ford) Spark Plug change process question

Congrats on the boat. I have the exact same engine you have. I tried everything from a grinded deepwell, universal, closed end wrech, and everything else I could find. I did not find any tool that would remove them. I almost had it with the grinded deepwell socket but everytime the plug would get close to being tight, it would snap the porcelain housing. I had to pull my exhaust manifold off in order to change them all.

 

[dubs283]

Re: '93 OMC 5.0L HO (Ford) Spark Plug change process question

you have to grind your deepwell so it is tapered on both ends - pretty much to the point of getting into the hex portion and socket end portion

it will look kinda like a football with blunt ends when you are done

this is the only way i have found to deal with those darn omc ford manifolds

 

[Jono69]

Re: '93 OMC 5.0L HO (Ford) Spark Plug change process question

Thank you guys for the advice. I forgot I had a spark plug t-handle tool in my other boat. I am going to try that before I pull off the exhaust manifolds. I'll keep everyone posted. Hopefully I can get to it in the next couple days.

 

[airdvr1227]

Re: '93 OMC 5.0L HO (Ford) Spark Plug change process question

Hard as it may seem to believe, you need a box end wrench. The 351W is every bit as tough at the 5.0. I swore I'd never do it again, or I'd remove the manifolds first.

 

[hshift]

Re: '93 OMC 5.0L HO (Ford) Spark Plug change process question

I feel your pain! I have the exact same boat and engine. Using various length sockets and extensions it was a nightmare. It took me two hours just to do one side, and another two for the other. Getting a socket on the plugs is not so bad, but no matter what extensions/u-joints I used you can only turn the ratchet a very small amount due to the lack of space. I have long fingers, so I was able to contort my arm enough to hand thread the new ones in a bit. Needless to say my arms were sore for a couple of days after I was done. Good luck getting it going.