Just finishing the 15 hr service after rebuild on my UL350iS.  Required a torque check on the cylinder head bolts.  If torque has loosened (not uncommon) you need to retorque all 16 cylinder head bolts.  Each cylinder has two of the bolts which are not accessible without a bit of extra work.  The bottom cylinder bolts required removal of the valve cover, lock tab and cylinder head plug.  Get at it while checking and setting the tappets.  The top cylinder head bolts require lifting the inlet manifolds about an inch or  two to access.  When going to remove the inlet manifold bolts, I discovered one that was completely loose (despite nordlock washer) and could be removed with my finger. Closer inspection revealed stripped threads!  I already had a proper helicoil kit for the M6 bolt size since I had inserted one helicoil already for a stripped exhaust bolt hole. Anyway, got it done today and should be able to do test runs later this week.  The good news is that the engine so far has been running well, no prop flange issues as of yet with the new crank and prop flange and WW prop.  Also note that the 5 and 15 hr prop flange bolt torque check has been eliminated if new engine or rebuild by factory/authorized repair station.  The picture below shows the freshly tapped hole ready for helicoil insert.

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NGK plugs are on order and currently lost in transit. Will not know numbers until they arrive. Any parts house should be able to cross reference numbers.

Bosch FR5DTC, my last ones were made in Russia, maybe why I am having a difficult time ordering Bosch.

Fine fuel filter:

Wix 33008

Parts Master 73008

Good luck finding fuel pump.


Thanks for the info...


It turns out that NGK plugs have two electrodes vs three on the Bosch. I ended up ordering the Bosch online. The senior parts man at the auto parts store believes that Bosch and E3 are the only two companies that make three electrode plugs. The Bosch plugs are made in Russia, that may impact availability.


I noticed that as well.  I also have a set of unused plugs in the Hangar and also see where they came from Russia.  Maybe UL power needs to consider finding an alternative?

Interestingly, I just went back to the UL Power oil filter and using a hose clamp for a safety wire attach point.  I had been using the K&N filter because of the hex nut and drilled hole for safety wire. I was not worried about any sort of factory warranty when I switch to the K&N.  With an overhauled or new engine under some sort of warranty I would consider using only the UL specified components...you know - just in case there was an issue of some sort ;)


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