1984 FXSB Shovelhead. Owned the bike for 6 years. A previous owner had engine work done (dual plugged OEM heads, S&S 80" jugs, Crane cam...) I honestly don't know the full extent of all the work done internally but it has been a rock solid engine for 6 years. Never had to open it up for anything..... but....
The rear plug gets oil fouled after a bit. Has done it the entire time I have owned it. I'd finally like to at least pinpoint where it's comin from and resolve.
I just put these NGKs in a few hundred miles ago. The rear plug as you can see is gettin oil fouled already. Notice only half the plug is getting fouled it appears. I wonder if this is where it faces the valve guide?
Here's the front plug. Looks like my jetting is pretty clean according to the front plug....maybe a tad rich:
Before I take a wrench to this I wanna do a compression test and leak down test to rule out any major issues.
It seems with shovels this type of problem is *usually* due to either a bad guide, bad valve seal or a compromised head gasket at the oil return.
Am I on the right track here?
The rear plug gets oil fouled after a bit. Has done it the entire time I have owned it. I'd finally like to at least pinpoint where it's comin from and resolve.
I just put these NGKs in a few hundred miles ago. The rear plug as you can see is gettin oil fouled already. Notice only half the plug is getting fouled it appears. I wonder if this is where it faces the valve guide?
Here's the front plug. Looks like my jetting is pretty clean according to the front plug....maybe a tad rich:
Before I take a wrench to this I wanna do a compression test and leak down test to rule out any major issues.
It seems with shovels this type of problem is *usually* due to either a bad guide, bad valve seal or a compromised head gasket at the oil return.
Am I on the right track here?
Comment