Thread: attn yamaguru's
07-10-2007, 01:42 PM #1
maybe someone here could shed some light on this problem. i built an 03 1300 for a customer with the following mods.
- riva 150 psi heads
- flame arrestor
- efi controller set at 6617
- d plate
- cat chip
- 14/20 dynafly with 06 pump
i tested it and ran 72 mph @7160 rpm.
customer went out on it and seized the rear piston after 1 hr.
i rebuilt it with 3 new pistons because 1 and 2 were .010" clearance(well out of spec)
i also learned the customer was using 87 octane so i figured that may be the cause.
filled with 93 octane and retested. ran great.
custome took it and rode around slowly breaking it in. gave it full throttle and seized within seconds. rear cylinder again. pulled it apart. rear piston has rich looking burn pattern but does have minor deto pecking.
i have checked...
engine leak test...ok
crank phase....# 3 is .010" higher in bore than #2 with #1 @tdc(ok imo)
compression before failure 155 psi
what am i missing? what are some of the common parts to fail on this thing? i assume at this point it is fuel related but not sure
07-10-2007, 01:48 PM #2
Mark, try to get a hold of wfo. Feel free to call me. I know a little. I'll send you a pm
07-10-2007, 06:44 PM #3
- Join Date
- May 2005
It could be a bad controller. I would use a Free Flow and make sure to run 5 pounds less on the 3rd cylinder head and dump the water on this cylinder overboard . When you say rich looking burn pattern, you meant ...No wash at all?? You did say that he seized at WOT???
Have you presssure tested the water jacket system.
Which flame arrestor???
07-10-2007, 06:50 PM #4
-Water ingestion would be my first guess.
-Pressure test the engine. Could have a blown rear seal.
-Cylinder base gasket on 180deg out (but the other two would be bad.)
-Injector issue or someother FI issue.
07-10-2007, 07:13 PM #5
how long did the customer break the ski in for before giving it full throttle?
07-10-2007, 07:14 PM #6
Did you have the rear cylinder re-nikisil'd or just replaced it with a new one?
07-10-2007, 10:23 PM #7
07-10-2007, 10:25 PM #8
07-10-2007, 10:25 PM #9
07-10-2007, 10:27 PM #10
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