Even the earlier non-vented version has XPS on the top. Nearly bought a few of them off E-bay, it would have been bad! Best to turn it over and verify the green duck bill and pinch the wide part and make sure it opens. FWIW
doo oil cap related burn down?
- Thread starter Lorduss
- Start date
Even the earlier non-vented version has XPS on the top. Nearly bought a few of them off E-bay, it would have been bad! Best to turn it over and verify the green duck bill and pinch the wide part and make sure it opens. FWIW
P
Polarisbird
Member
TRS can you please post the correct part # for the duck bill cap?
Thanks
Thanks
The one we use is 519000273 , TRS posted it last year.
P
Polarisbird
Member
Ok thanks!, that's the one I ordered but I thought I better double check.
Okay what is the verdict Lorduss . Let see some pix of the engine .
Love the analogy! LMFAO!
final verdict is in, lower pto side crank bearing seized and started slopping around
thanks to that the pto side piston met the top of the cylinder dome, piston took a light punch but the rest looks fine
scuff marks on the intake side of both cylinders
looks like it scratched into the nikasil, not very happy with that
no bubbles in oil lines except for right at brass nipple seen the day after
although I don't believe it is the oil cap at this point, just to do it I sat the oil tank upright and it dripped to a stop, im sure a few psi will change that
and I will eventually do a test on that
motor ships off to indy dan tomorrow, and pics coming in a bit
thanks to that the pto side piston met the top of the cylinder dome, piston took a light punch but the rest looks fine
scuff marks on the intake side of both cylinders
looks like it scratched into the nikasil, not very happy with that
no bubbles in oil lines except for right at brass nipple seen the day after
although I don't believe it is the oil cap at this point, just to do it I sat the oil tank upright and it dripped to a stop, im sure a few psi will change that
and I will eventually do a test on that
motor ships off to indy dan tomorrow, and pics coming in a bit
The failed bearing
the mag side
both pistons looked and felt exactly the same, both cylinder walls felt the same, I think some debris bounced around in there
The scratches in the cylinder wall feel deeper than what I could feel on the pistons, felt nothing on the rings
the mag side
both pistons looked and felt exactly the same, both cylinder walls felt the same, I think some debris bounced around in there
The scratches in the cylinder wall feel deeper than what I could feel on the pistons, felt nothing on the rings
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I don't know what rust you are seeing
The marks on the piston are from the piston meeting the top of the dome, the rktek domes have patterns cut into them, when the bearing seized it flattened rollers and gained about 1/4 inch of slop, s
Allowing the piston to meet the top of the dome in direct contact
Oh, I get it...I didn't just fall off the turnip truck.
I've been an aircraft mechanic by trade for the last 30 years, so I think I understand fluid dynamics.
I just don't trust the duckbill design as much as a true vent.
I've seen a few rod bearing failures.
A lack of oil will take out the top end far before the bearing. A lean/ sqeek.
Usually a history of detonation even minor hastens rod bearing failure.
(A common rktek trait)
Summer storage is critical.
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even when running 130-140:1 fuel/oil in the tank, a top end is likely to go before the bottom end?
any other evidence of RKtek det issues?
im still leaning towards poor summer storage on my part, although when doing my top end my top roller bearings looked in perfect shape to my surprise.
so I did not expect my lower conrod bearings to look any different at the time.
See the pictures trs posted of an oil delivery failure.
The bottom end should be a bath of oil if it keeps pumping. The top end dries out first and with the injector spraying at the intake skirt.......
In 12-13 a bunch of guys were posting about det with the rev1 and rev2 drop in kits. Was helped with good fuel.
Back in the rev days i had an rktek drop in kit that was very prone to det and i had to overfuel the thing til it was slower than stock to keep ring locator pins in place. I learned my lesson the hard way.
Light det will sometimes not even trigger the det sensor but will tear up the rod bearings.
Likely as you said though.
The lower rod bearing is the smallest vs the actual amount of rotation it gets. Usually the weakest link after a humid summer storage.
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