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Maybe an engine issue ? [message #315761] Sun, 09 April 2017 19:56 Go to previous message
Matt Colie is currently offline  Matt Colie   United States
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma:
Senior Member
The vast majority of my engine experience with engines that are highly instrumented and closely monitored. If I had that level of instrumentation, there would be very little room left in the coach for us.

On the Shawnee run, our fuel rate and lube oil consumption have both gone the wrong way. I am used to clocking 9.2 MPG and about 2k miles on a quart.
This run was 8.48 and a little over 1K/qt. This is new. There is oil on the bottom that might account for the lube oil loss.
I just inspected the plugs and they don't match very well. These are XR451X gapped at 0.047.
The last set didn't match that well either, but much better than this. I know I saved them and got them out to compare. Those were Bosch WR9FPZ gapped at 0.040. Those bothered me because the center electrode can recede into the insulator and you would never know.

The plugs are not what I expected at all. The front pair (1&2) are so dark that they could be fouled, but it is not oil. Those should be the two that are hottest. The rest of the odd side (3,5&7) were much darker than the even side (4,6&8). 8 almost looks too hot. I really am hoping that this is not telling me something I don't want to hear.

There is no running trouble at all and she is as smooth as ever.
Tomorrow I am going to rearrange the plugs and put the darkest were the lightest were and vice-versa.

Matt



Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
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