1988 mxp 25 bubbles around injectors

[Terry Forshier]

I changed out the last fuel line fuel line on my engine. (from the lsat injector back to the motor) After i startd up I noticed that looking straight down on the motor that the middle injector was bubbeling around the gap where the injector screws in. I thought it was just fuel spillage into the crack. Today a few days later, i checked and I still have the small bubbles around the injector and fluid (I suppose it is fuel) in there. Then I noticed that the top  (highest ) injector is also leaking some and this area has a black tar like ring around the injector where the fuel has "gelled" as lack for a better word. I tried to see if the injectors were lose and it didn't seem like it but it is hard to get any kind of wrench on it.
Motor seems to run ok, I have thought for awhile that it was not very powerful though. Top end 5.7 kts. 3 blade std prop. I changed glow plugs a few months ago.
This is not normal but ?. ideas appreciated.
Terry

[Ron Hill]

Terry : There are three seals on each injector :
1. The fuel inlet on the top
2. The "banjo" seals around the mid to the fuel return
3. Where the injector holder screws into the head

I'll guess that you have one or more of these leaking.  #1. is a compression fit, while # 2 & #3 have a crush washers on them. 
The bottom line is that you are loosing compression and/or fuel !!  This is NOT normal.