Spark Plug Gap 50HP Merc

[Jesse75]

Serial # 0G270011 1995 or 1996? 50hp fourstroke EFI

Trying to verify what model of NGK spark plugs to use.

NGK has this....

Year

Engine

Model

Standard Plug

V-Power Plug

G-Power Plug

Iridium Plug

Platinum Plug

2001-1995

50 HP

50, BIGFOOT

n/a

n/a

n/a

n/a

No Year Listed

50 HP

FOURSTROKE 50 EFI BIGFOOT, EFI

n/a

n/a

n/a

The top one uses standard plug. NGK-DPR6EA-9 and no Iridium GAP is .035
The bottom uses standard plugs NGK-[FONT=Arial, Helvetica, sans-serif]DCPR7E and Iridium DCPR7EIX. GAP is .031[/FONT]

[FONT=Arial, Helvetica, sans-serif]Mercury parts catalog is saying NGK-DPR6EA-9
I'm just confused if I can use or should use the Fourstroke EFI with no year listed Iridium plugs?[/FONT]

 

[Jesse75]

This is off of Iboats. I have a 1996 4-Stroke EFI. but they never have EFI listed on any charts. The 2006 can take a DCPR7E. NGK parts list says it gap is .031 here it says .035?

50	504-cyl. 4-Stroke	1995 - 2001	DPR6EA-9 (1)	-	-	0.035
50	503-cyl. 2-Stroke	2001 - 2006	BPZ8H-N-10 (1)	-	-	0.040
50	504-cyl. 4-Stroke EFI	2006	DCPR7E	-	-	0.035

 

[quicktach]

Why not go with the Merc part catalogue?

 

[Fun Times]

You have a 1995 model number 1F50412RD.

The safest thing to do would be to stick with NGK DPR6EA-9 / Merc OEM part number 33-827858Q as that is what is coming up under your serial number.... I have personally noticed in the past that the NGK website doesn't always seem to 100% correct at times on the marine side.

Typically you should be able to find the correct gap size on a sticker someplace on the engine.

 

[Jesse75]

Thank you. I went ahead and put the standard ones in. Just thought Iridiums are supposed to be better, and didn't know if I could switch.