Broken Denso Plugs, Why I choose Champion Sparkplugs PICS

[Mike Thurman]

I recently serviced a couple boats for a state agency I take care of. Both boats have 6 cylinder angle valve Lycomings. They both had Denso Plugs. On the first boat I had one Sparkplug break off. On the second boat I had 4 break off. All on the top plugs. The angle valve cylinders have a little pocket that will hold water around the plug. Denso plugs are not plated like the Champions which allow them to rust up faster. You can also see the small amount of metal on the plug for the socket to grab as compared to the Champion plugs. I thought I learned on the first boat so I ran the motor and got the cylinders hot and used all the PB Blaster type stuff for rusted threads. Talk about a chore to get these plugs out. It took a couple hours to get them out,but I got them.

 

[Mike Thurman]

 

[Mike Thurman]

 

[Geneva0550]

Mike, What about the NGK WR5 plugs? I have been running them in my 0550 and they seem to do ok.

Dave

 

[Mike Thurman]

I have only used and will always use Champion Plugs. They have never let me down. The Autolite plugs are not plated either they rust fast. I have never looked into the NGK plugs. I have a dirtbike that I run avgas in. It will not run on ngk plugs. NGK plugs lead foul in my bike. I run Champions in it and never had a problem since. Kind of weird but it will not idle on avgas and a brand new NGK plug.

 

[Geneva0550]

Mike, I may try the champions on my next plug change. I used to run the D16 in the lycomings I had and the gpu as well. I don't remember ever having any problems. Will the D16 work ok in my motor? I have an 0550 crank with0520 pistons which are taller giving it more compression.

 

[Mike Thurman]

Go with a D-14. It is a cooler plug than the UD-16 or D-16. In Champion plugs the higher the number the hotter the plug.

 

[GatorChaser]

Spray plugs with silicone after you tighten them down, they will never rust no matter what type, a little preventative maintenance.

 

[hmgm123]

I wonder if AC makes a plug for aircraft?

 

[deepsea diver]

Have you ever tried a light coat of anti seeze on the threads. Our outboard engines get soaked with salt water. Have never broken one off.
Just a light coat.

We were just talking about those plugs. Buck thirty nine compared to Six bucks.

HMGM, you better start spraying, now!!!

 

[Mike Thurman]

These are State owned boats that were not on a good service schedule. I always use anti seize. What plugs are six bucks that you are talking about??

 

[grant]

I have had real good luck with Bosch plugs...less than $2 bucks a-piece...seem to outlast Champions...not good in an oil burner though.

Grant

 

[deepsea diver]

MT, just the mark up by one of the AB companies up here in central Fl on the east coast. Just your good ol normal plug.

 

[Mike Thurman]

Six bucks huh, well I guess I need to raise my prices......hahaha

 

[CumminsPower]

I ran champion D-14 in my old motor and had great lick with them. And after a few seasons of duck hunting on them the had rust in them but had no problem getting them out. I always liked them. The I was able to change all 8 of them for only 16 bucks.