Carb Floats Service Bulletin

[Randy Roth]

Hello All,

With Phoenix s/n 19 and up needing compliance with the SB 912-065 , I thought we could get a thread going.

Possible items... Compliance, actual date of SB and thus 1st no fly date without out compliance - (under 25 hrs. flown), Warranty, Experience, Parts & NEW FLOAT AVAILABILITY, etc.

Thanks, Randy Roth # 26

[Eric Greenwell]

Possible items... Compliance, actual date of SB and thus 1st no fly date without out compliance - (under 25 hrs. flown), Warranty, Experience, Parts & NEW FLOAT AVAILABILITY, etc.

Here is my understanding:

1. There is a revised bulletin that is easier to understand, but with the same requirements: SB-912-065UL R1 (Nov 13, 2014)
   
2. The start of the 60 period is still from the original SB issue, which I believe makes Dec 6 the last day of that first 60 day period
   
3. Since it is not an AD, I believe I can legally fly the plane after the 60 day period without accomplishing the inspection; however, I can't quote the FAA or any regulation on that interpretation.
   
   1. 
      
   2. I don't know if Rotax would still honor my engine warranty - asking Rotax might be worthwhile
      
   3. I don't know if my insurance would still be in effect - asking Costello might also be a good idea
      
      
   4. As long as the engine runs well, especially at low RPMs, e.g. idle to 3000, the floats are fine.
      
   5. A mechanic I asked about the situation said he's seen only one bad float in all the engines he's worked on, and it's his opinion that as long the engine is running smoothly and the temperatures are normal, the floats are OK.
      
      1. "Temperatures" includes the EGT: You will see one EGT going much colder than the other until you get to 3000 or so RPM.
         
      2. Since the bad float is slowly absorbing fuel, it seems unlikely this would cause an engine failure without a lot of warning.
         
      3. He has not been told when properly manufactured floats will be available.
         

The situation is frustrating to me, since the nearest authorized mechanic is 200 miles away on the other side of the Cascade mountains, and crossing them in the winter is problematic. Getting a mechanic to drive over from Seattle to my hangar would be a possibility, and now I'm wondering if my warranty covers something like that.

[Gfeldman]

Hi all,

I called the Rotax service center in Lititz, PA and was told that Rotax is not replacing any fuel saturated floats with existing ones until they have a fix for this problem. Clearly the pressure is on Rotax since so many other LSA's are affected. I haven't been able to find any kind of direct response from Rotax.

George Feldman

[Eric Greenwell]

I've posted this at Jim Lee's request, as this website is balking at his cut and paste attempts.

With Phoenix s/n 19 and up needing compliance with the SB 912-065 , I thought we could get a thread going.

We just flew a new Phoenix to Lockwood Aviation in Sebring for the 25 hr engine check and oil change. Everything looked good except for the carb floats in one carb (not the other one). Once again, they were impressed with the engine installation in the Phoenix. Besides the Rotax mechanic who did the work, Doc and I met briefly with Dean Vogel, the guru of the Rotax engine, and the guy who mans the Rotax booth at all of the major airshows.

We asked about the test procedure using a syringe and were told that the only way to really check the floats was to weigh them or see where they float in the bowl. They must weigh between ? and 7 grams. The 2 floats in one carb weighed 7.3g which is outside of the allowable range. So the mechanic had to replace them. So yes, Rotax mechanics are replacing bad floats. But get this, they were replaced with floats which were exactly the same, manufactured by the same company which makes the "defective" floats. At this time there is no proven replacement, and the floats you re-install can be just as defective as the ones you took out! As previously stated, there is no carb float final solution yet. My unanswered question, is what about the original floats which are not affected by the bulletin, aren't they suitable replacements?

When Dean heard that the floats were .3g out of compliance and were replaced he rolled his eyes. (The mechanic is just following the bulletin). He said that as long as the floats "floated" in the bowl at the same level as the pin which goes through them, they are fine, and suggested this as the ultimate test. He said that a rough running engine as described on this forum would precede any "sinking" floats that needed to be replaced.

The engine on this plane was running as smooth as a purring kitten at all rpms before we took it to Lockwood. No ethanol has ever been in this engine. The floats would probaby have "floated" near the pins as explained by Dean.

This Phoenix was certified by and received the airworthiness certificate by the FAA DAR who does all of our planes. He is somewhat of a "top dog" in the certification business with LSA, Experimental, and Standard Category aircraft. He told me that as this was an SB (Service Bulletin) and not an AD (AD's do not apply to Light Sport) he has no authority to check for compliance on this bulletin.

Therefore this bulletin is between the engine owner and Rotax. How it applies to the engine warranty or to the insurance companies I cannot comment on. Beware of anyone who professes to know the answer to this without consulting with Rotax or your insurance company. To my knowledge everyone on this site has been pretty good about sticking to the facts and not conjecture, which is the main problem I have with forums. Keep it up! But I must say that I make it a point to not ask leading questions to insurance companies or the FAA.

Don't quote me but I believe that the cost of the floats ($65 each) is covered by the warranty but not the labor. As to the warranty covering mechanics travel expenses, good luck with that one!

Randy mentioned monitoring the EGTs. They are typically between 1300 and 1400F and usually sit around 1320F in cruise flight.

By my count, the Cessna 172 has 55 AD's on it which must be complied with. Compared to that venerable aircraft, we are doing pretty well with our Phoenix and the Rotax engine. I am about to depart across the Gulf of Mexico to Bogota on November 27, weather permitting. I'm not worried about the carb floats.

It may not seem like it right now with the polar express hitting most of the US, but nice days do exist in the winter across the US. Pick a nice day and go see your mechanic, have him check out your floats, and carry on. Just my 2 cents. I am not a Rotax mechanic.

Disclaimer: Any statements regarding matters made herein, blah, blah, blah, blah,.....cannot be relied upon or used by any person and are not intended to be used or referred to in anyway, blah, blah blah......

[Randy Roth]

Hi All,

Good News on the carb float SB. Kevin Kahne of California Power Systems is taking names to ship the replacement float kit in the next, "2 to 3", weeks. I ordered mine yesterday. CPS's # is 800 247-9653. Kevin said, " the new floats are marked with a dimple and further tested to approval". Ah, the light at the end of the tunnel.

[Randy Roth]

The new floats are in and all is well. The replacement is pretty easy. The Rotax-owner.com training videos are very helpful. I didn't need to take the drip trays off as shown in the videos for carb rebuilding. Just loosening the forward clamps allowed the carb to be slid aft and rotated so as to replace the floats and gaskets. By the way, be sure to get reimbursed if your engine and carb serial numbers fall within the range specified in the SB. My parts came with the form to list the serial numbers and receive parts only reimbursement. Total time start to finish ... about an hour plus paperwork. Randy Roth #26

[Dave]

I just received new improved floats from Lockwood. Will have them installed at 100 hr check. Meanwhile, engine runs fine and steady. Using 100 LL since there is no ready supply of ethanol free fuel here in vicinity of Princeton, NJ.

Dave Glosser