Mercruiser 260 - What's the trick to change the plugs?

[Alwhite00]

I Changed the plugs in my mercruiser 260 and it was a royal PITA - I'm going by feel as I can not see anything and my engine is under the floor. I managed to get them all in but think I might have cracked one. Ths spark plug socket hits the exhaust manifold severly and puts everything in a bind.

I ground down the socket to see if that would help but it was marginal if any different. Any tricks or suggestions to make this a smoother process next time?

LK

 

[rpaldrich]

Re: Mercruiser 260 - What's the trick to change the plugs?

Same engine same problem. Try disconnecting the cooling hoses to gain better access. I had to do some acrobatics to hold the spark plug socket "just right" or it would go on the plug all the way and bind on the engine. I'm hoping for a better solution next year-impossible to tell how tight you are making the plugs

 

[ktbarrentine]

Re: Mercruiser 260 - What's the trick to change the plugs?

5.0L in a 1990 20' Chaparral. Similar issue...and yes, it is a PITA! I had to grind down my plug socket a great deal. First time in, I broke two plugs because of wrench binding on the exhaust manifolds. I can just offer to have patience, a well-ground wrench, and good acrobatics. I also used a swivel extension that seemed to help, but you still have to be careful... Also check to make sure the plugs are at the correct tightness... My fear of not wanting to break another plug caused me to not adequately tighten the one at the back stbd side (above starter). Glad I double checked after an hour on the lake... it had backed out a few threads. I'll be watching this thread for any other tricks people have for this.

 

[Don S]

Re: Mercruiser 260 - What's the trick to change the plugs?

You have to rework a spark plug socket to clear the manifolds.