Rotax 912UL - REVISED Service Bulletin SB-912-063 UL Revision 2

[dholly 718]

Rotax announces REVISED Service Bulletin SB-912-063 UL Revision 2 with expanded serial number ranges of fuel pumps and engines affected!

 

Rotax has released an amended engine serial number list for UL engines affected by this fuel pump SB.

In accordance with the current "LINE" Maintenance Manual all mechanical fuel pumps have a 5 year life. Fuel pumps prior to 2008 (with S/N starting 07. or 06.) should have already been replaced in line with the routine maintenance requirements. If this 5 year replacement has been omitted the pump should be replaced immediately. It is necessary to check the part no. & S/N of any pumps previously replaced to ensure that they are not in the affected range.

NOTE: Basically, all fuel pumps with part no. 892542 and part no. 892546 are affected. Pumps with serial numbers(S/N) as listed in the SB-912-063UL R2 as originally installed in the engines and/or delivered as spare parts are also affected by this replacement recommendation. In all cases owner/operators should check their existing engine and fuel pump serial numbers against those listed as affected in the most recent release of this SB to assure they are in compliance with requirements.

For UL (Uncertified) engines, http://legacy.rotaxowner.com/si_tb_info/serviceb/sb-912-063ul.pdf'>CLICK HERE to view latest revision of this UL Service Bulletin covering a broader range of affected fuel pumps and engines.

Certified engines are not affected by this revised Service Bulletin.

Rotax-Owner.com has previously released a VIDEO to help clarify in detail the steps required to comply with this latest SB Revision. For more information, view Rotax-Owner's video.

 

[edit] update link

Edited 29 Sep 2013 by dholly

[dholly 718]

For those who have complied with this SB, you know the new style 893110 fuel pumps include a new drain line nipple.

I'm curious to see exactly how folks have routed this drain line (got pics?) and if they have experienced any fuel drainage?

Rotax SB-912-063 R1 HERE says:

3.6.3) Check drain line

NOTE: A slight leakage on the drain line can be attributed to a slight "sweating" and not considered to be a issue. For a period of 1 minute after the engine has been stopped, no liquid must drip down. In case of uncertainty determine the oil amount. The maximum leakage is 0.5 ml for a 20 min engine run..

Also, the new fuel pump mounting hex nuts require tightening torque 15 Nm (133 in.lb), but you can't get a standard socket straight on them. Not sure a crows foot would work very well either. Anyone have a suggestion or source for a 11mm torque wrench extension? Don't need a $200 set!

[akflyer 1427]

Can you just make a block off plate and run an electric pump?  The prices of these things are stupid when you can run and electric pump for about 20 bucks.  hell even put 2 in there so you have a back up. 

 

I'm not a 912 driver so I don't know if you can put a block off plate on it like you would a chevy V8, but from the picture it looks like it will operate the same basic way.

 

[EDMO 1078]

Doug,

      There are formulas available for calculating the change in torque values when a crows foot or box wrench extension is used.

I don't know where mine are right now, but you should be able to find the conversion charts.

     I am with Leni - If I had one of these engines, I would think seriously about running 2 facet or other electric pumps instead of paying the outrageous prices they want.

EDMO

Edited 30 Apr 2014 by Ed In Missouri

[dholly 718]

Never thought about doing that Leni. In fact, I've never even heard or read about anyone else removing the mechanical pump on a 912 either. Which makes me wonder if something specific precludes the use of electric pumps only. I do know the 912UL and ULS both seem very finicky regarding fuel pressure, that was one reason I asked in another thread if anyone using the MGL E-1 had wired in a fuel pressure sender. That fluctuating fuel pressure issue can usually be traced to a failing pump or the fuel system plumbing. Other than the recent fuel pump weep issue I experienced, I've had no problem with fuel pressure with my 80hp 912 in the KF4 (at least, that I know of) but I do want to monitor it now. Leaning toward installing a FACET backup in this plane. Also, a low fuel warning light is on the To-Do List, probably when I replace the current high mount header with a behind the seat aluminum header tank. IMHO, that location makes for better plumbing and provides a tank fitting for the low fuel sensor.

There are notes in my Aerotrek log that fuel pressure has been problematic. It had one replacement pump even before the Rotax SB. No engine outs but widely fluctuating pressure and several instances where the needle went to zero. That plane has a 912ULS and is plumbed with a return line to the header tank so I think the replacement pump was likely a bad pump too. I already installed another new (pre-SB) pump that came with the plane, but haven't tested yet. In any event, I took advantage of the special Rotax pricing after the SB and bought two, so I still have one new, improved spare pump sitting on the parts shelf if that one proves to be problematic too.

Ed- I am aware of the issues requiring a conversion calculation when torquing on an angle, or if an extension points straight out of the torque wrench. However, if you attach the crowsfoot at a 90* degree angle to the torque wrench, then bolt torque equals the wrench torque setting regardless of how long the crowsfoot is. So if I can actually get to the bolt with the crowsfoot at exactly 90* degrees, no such conversion calculations are necessary. I can't use the 'standard' short crowsfoot to get to the bolts, so I'm looking for a long 11mm crowsfoot to fit either a 3/8" or 1/2" torque wrench head.

[akflyer 1427]

Any chance you can heat up and bend an 11mm wrench then weld a socket to the end to hook to the tq wrench?  You could then to the math to figure out the additional leverage you now have.  One thing I have done i nthe past on problem bolts ot to use the tq wrench on a bolt I can get to, then put an end wrench on same bolt and "feel" the amount of pressure I have to put on the wrench to get it to slightly move.  I then use that "feel" to tq the other bolts.  If you really want to be anal about it, you can use a digital fishing scale on the end of the wrench and use it to pull to see how much pressure you have to put on it to achieve the desired tq. 

 

As far as electric pumps, they are pretty damn steady in the pressure they put out, and you can always jump a pressure regulator in line and set it at EXACTLY the pressure you want at the carb.  I had to do this on my snogo as the Arctic cats like 41-42 PSI on the fuel injection and from the factory they were running around 48.  This led me to have shit for power and I left a nice big black streak in the snow when ever I would stop for a moment then take off again.  I installed the pressure regulator and set it and have not had any issues in over 6000 very hard ridden miles.

 

[EDMO 1078]

Doug,

      After making the comment about spending big $$ for Rotax parts, I felt badly about what I had said - I was thinking experimental, where you can innovate without problems - then I realized that you may have been talking about the factory-built LSA, and you may not have the options of variations on it. 

      I still like the dual Facet electric pumps, and you can order them with check valves in either or both directions - I would opt for the check valve to prevent reverse flow, but none to check gravity flow.

      For 27 years as a toolmaker, I cut, bent, welded, made, about every crazy design tool that would do the job - Leni had a good suggestion about cutting, bending, a wrench and welding a socket on it - I have done that ten thousand times.  Low-hydrogen rod, and no quench works good for an arc welder, and either welding or brazing with OA works good too.  Just grind the chrome off first.  You probably know all this, but someone else might not.

EDMO

Edited 1 May 2014 by Ed In Missouri

[tcj 150]

For the 11 mm to torque wrench extension.  Ski Doo tool kits most have a 11mm X13mm open end wrench.  My craftman's socket set has a 3/8 socket wrench to square 1/2 inch adaptor.  The 1/2 inch end fits the 13mm open end wrench.  Or if you have an allen wrench socket set use an allen wrench socket on your torque wrench in the other end of an 11mm wrench.  The Chinese tool store or even local hardware probably has the combination you need for a couple bucks. 

Edited 2 May 2014 by tcj

[dholly 718]

I did try to jigger something up out of the tool chest but couldn't come up with the right combo. Good tip re: the SkiDoo tool kit, thanks. FWIW, my Yamaha xt600 tool kit has everything but an 11mm. I'm just gonna go have the airport mechanic do it, I hate to go this route because he and the FBO owner ALWAYS give E-AB guys shit and I'm sure payback will be a bitch!

[wypaul 448]

Doug the tool that you are looking for is called a torque adapter, if you do a search for 11mm torque adapter it will come up. Expect to pay $10-15 bucks and you don't have to deal with the guys at the airport. I would send a link but this site doesn't allow me to send links from my computer and IE .

http://www.cornwelltools.com/webcat/products.php?product=CTGM112TA-%252d-3%7B47%7D8%E2%80%9D-x-11MM-Torque-Adapter-12-Point

Guess I can paste from the IPad.

Edited 4 May 2014 by Paul S

[dholly 718]

Thanks Paul. I did search and found a 12-PC metric set with 3/8" drive for ~$85 shipped form Northern Tool. Think I'll go that route. might not be the most used tools in the chest but someday I will be happy to have the other wrenches.

http://www.northerntool.com/shop/tools/product_200603654_200603654?cm_mmc=Aggregates-_-Shopping-_-Hand%20Tools>Wrenches-_-28213

Edited 4 May 2014 by dholly

[akflyer 1427]

he who dies with the most tools in the box wins!  It never fails, the one obscure tool that you have not used in years and years is the one you need RIGHT now at 1 am and NO place in town is open to replace the one you just sold at a garage sale last week...