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ArlowCT
09-26-2012, 10:28 AM
I have never been that great at reading plugs, when you look at these, what do they tell you?

Thanks7130

mearstrae
09-26-2012, 10:48 AM
The top and bottom plugs look very rich (or oily?) the second one looks slightly rich (or oily?) and the third looks clean (possibly steam clean?). A brown plug is burning normally while a white plug is running lean. Black carbon deposits can be from oil or a rich mixture, smell or feel can usually tell which. A head gasket leak can allow for steam cleaning of plugs, and when the head is removed you'll have a very clean combustion chamber.

'95 R.R.C. Lwb
'76 Series III Hybrid 109
'70 Rover 3500S

I Leak Oil
09-26-2012, 10:57 AM
Are those the right plugs for your head? The thread looks awfully short.
Are the black ones wet with oil or are they dry and powdery?

jac04
09-26-2012, 10:59 AM
It's always hard to read plugs for someone else via pictures. If you want good feedback, post high-resolution pictures of each individual plug. Even with good pictures, you will only get feedback on the general running conditions, since it is almost impossible to see some things in pictures (like the tiny specs that occur due to detonation).

There is a lot of good info on plug reading. A quick Google search will give you lots of reference info.
Like this from Honda site: http://honda-tech.com/showthread.php?t=3063102

What plug # are you running?

ArlowCT
09-26-2012, 11:20 AM
Wow, I always know where to turn first. Everyone here is great.

So these plugs are from a friends truck in Ohio, I'm in CT, and this was the pic I received on my phone. I will try to get better pics.

The plugs did look short to me too. What are people's recommendations for plugs? This is a 7:1 motor if it makes any difference.

Thanks again!

stomper
09-26-2012, 01:27 PM
According to Terri Ann's site, either Champion RN11Yc or NGK BP6ES would be the correct plugs to start with.

I Leak Oil
09-26-2012, 04:41 PM
If they are too short making the heat range incorrect that will cause all sorts of issues with tuning, running and overall engine temps. Those plugs don't look like they are long enough to ignite the air/fuel mixture in the right spot inside the combustion chamber. No sense in trying to read them if they aren't he right plug. Have him run the right plug and then take some pictures of those.