DCPR8E spark plugs

[Guy on the water]

It looks like there might be 2 different stock numbers for the DCPR8E plug. I purchased 6 plugs today for my '03 GTX supercharged from an auto parts store. They are stock# 4179. I pulled the coil off the plug and peered down and noticed the tip is much more narrow than the plugs I bought. I figured I could unscrew the tip of the plugs I bought and then have a more narrow tip, but the tip is solid and does not unscrew. In fact, the spark plug box shows a picture of a thin tip with an "X" through it and shows a thick tip with a circle around it.

Every thread I searched here just mentioned DCPR8E, but it looks like that might not be enough info. to get the correct plug. I've done some more googling just now, and found this:

"DCPR8E stock #4339 is the one you need
DCPR8E stock#4179 has the solid non removable top"

from here: http://www.sea-doo.net/board/thread.asp?threadid=76302

This info is not on this site as I searched both '4339' and '4179'. This isn't news to most of you here, but helpfully it will help another noob down the road.

 

[kustomkarl]

The plug caps on all 4-tec engines require the tip be unscrewed from the spark plug. I buy mine by the box of 10... Be sure to only use the specified NGK plugs. Thanks for the heads up.

Here is some info on changing the plugs;

4-tec plugs NGK brand, DCPR8E Gap/ 0.7-0.8 MM or .028-.031in.

To replace the plugs remove the Oil dipstick, remove the plastic cover over the engine, replace the dip stick. Unplug the wire from the spark plug coil ( it's part of the spark plug cap) wiggle and pull the cap/coil out of the spark hole. Be careful not to break it. Loosen the spark plug, insert the cap/coil in to grab the plug and remove it. Gap the new plug, remove the screw top on the top of the plug, insert it in the cap/coil push it in the plug hole. Use a socket to tighten it. Snug it up go about 1/4 turn, loosen and snug it up(this compress the seal ring on the bottom of the new spark plug). Put some grease on the coil cap where it meets the cylinder and insert on the plug. Connect the coil wire. Do one spark plug at a time. Replace the plastic cover.


Karl

 

[Chris_cox]

karl i think guy is saying that there are 2 different versions of the DCPR8E plug

http://www.partsamerica.com/ProductDetail.aspx?MfrCode=NGK&MfrPartNumber=4179

http://www.partsamerica.com/ProductDetail.aspx?MfrCode=NGK&MfrPartNumber=4339

notice same plug number different part number

 

[kustomkarl]

I realize that, I just added to what he was saying....

Karl

 

[Chris_cox]

oh gotcha :cheers:

 

[Guy on the water]

You guys are on top of it. I can't recall when, but it seems like I've run into this before. That is, multiple versions of the same plug name. The stock number (the 4-digit) apparently is of greater utility in selecting the right plug.

As far as greasing the coil cap goes, there was a purple-ish grease/residue when I took out the coil... and I don't have any suitable grease for this application. Is there one that you'd recommend? Is the point of the grease to provide a moisture-proof seal or to ease install/removal?

 

[kustomkarl]

It works kind of 2 fold, but it will make it easy to remove and install.

We try to help the best we can. All the mods here are volunteers and make nothing for helping. It's just good to use our knowledge and expertise to help out.

Karl

 

[Chris_cox]

your best bet for the coil boots is a dielectric grease

 

[kustomkarl]

Chris, it's not for contact, it's to help slide the coil assy. into the spark plug hole. The coil is actually the plug cap. The grease also keeps out the water from around the plug. To get to the cylinder head the plug is like counter sunk almost 3 inches deep.

Karl

 

[Chris_cox]

i know its just like most coil on plug setups just a lil tighter fit, i had mine off the other day before going out