Carb rebuild question

[Roger Lee]

Hi All,

 

Here is your extra credit test question for today.

(There is no written time table for this rebuild, but the 5 year hose replacement is a very good time.)

This does not include just an inspection.

 

Who is allowed and what credentials does someone need to rebuild a Rotax carb on an SLSA or our CT?

(Rebuild means to strip it down clean and replace all "O" rings, and most internal applicable parts.)

[Tom Baker]

It used to be heavy maintenance, but can now be done at the maintenance level. Tom

[Mac Bowden]

Dead easy this one...... ME

Mac

[Roger Lee]

Hi Mac,

 

 

The answer is Leprechauns in your part of the world.

[Roger Lee]

Hi All,

 

Answer:

 

 

The 200 hr. is not the same as a rebuild. The 200 hr. is just what it says, an inspection only and no parts replacement except the carb socket, floats or diaphragm if necessary. You need only to check the carb socket, carb diaphragm, bowl and maybe the float level. Flush with a carb cleaner for any dirt. That's it.

It does not require any parts replaced. So the 200 hr. is mainly a look and clean as need be on exposed parts. If you disturb any of the "O" rings they are supposed to be replaced and that starts into the carb rebuild side, which Line maint. can't do. carb rebuild is removing and replacing parts within the carb. We just went over all this with Eric Tucker in the update class. I also just got off the phone with Jeremy McGregor of CPS in California about this and he confirmed with me about both items. We tried to lobby to have the carb rebuild moved to the Line maint. section, but Rotax refuses because carb rebuilds are done so infrequently that Rotax doesn't think people can keep the skills for this up and yes you can get in trouble by doing some wrong things to the carb or not doing them.

Bottom line is Line Maint. can do a 200 hr. inspection, but you have to be Heavy Maint. rated to do a carb rebuild.

[Runtoeat]

I'm trying to educate myself regarding what must be done for Rotax maintenance. I see that the Line maintenance manual calls out the hose replacement at 5 years in Sec.2.1. but I don't see where there is any call out for a "carburetor rebuild" in either the Line or Heavy manuals. Is the carb rebuild something that is recommended or is this shown somewhere on a scheduled maintenance list?

 

I also see that there are differing opinions as to who can do a carb rebuild. Roger indicates only a certified Heavy Rotax repair and Jim indicates someone with a Maintenance rating can do this. My plan for rebuild, if this is required, will be to remove the carbs and send these to an Rotax certified repair facility.

[Roger Lee]

Hi Dick,

 

Don't confuse a carb inspection with a carb rebuild. It is two completely different things. The carb inspection is spelled out in the "LIne Maint." book and the carb rebuild is spelled out in the "Heavy Maint" book and this shows where the rating falls not to mention Eric Tucker of Rotax teaches it this way in class. No where in Rotax classes or in the "LIne Maint" book does it say you can or how to do a carb rebuild. You are only allowed to do what is is in each book for that Rotax rating. If it is in the "Heavy Maint" book then that is what rating you need.

The 5 year rubber replacement includes not only the rubber hoses, but the rubber parts of the carb. That is the carb sockets, the carb diaphragm, vent tubes, the rubber cross over tube rubber on each side and I would personally include the Viton tip needle. If it has been 5 years and you have the entire carb off and replacing some parts you might as well replace the "O" rings and the other few parts and start off with a new carb so to speak. Why do it half way and look for other issues before the next rebuild. It will cost you double the labor and parts later, so you might as well save a little time, money and other problems and do the whole thing.

 

So the 5 year does not say to "rebuild" the carb, just some parts, but it wouldn't be very prudent not to include the other few parts and the labor is already being paid anyway.

 

No where in the Rotax manual does it give any specific time line to do a complete carb rebuild, but you can run your car and never change the oil for 100K miles, but it isn't very smart.

[Runtoeat]

Roger, thanks for the info. I'm getting my ducks in a row for the 5 year rubber replacement next year and trying to understand what is required of me to do this. I do understand the difference between the 200 hour and the full rebuild of the carbs. I found the 5 year rubber replacement and knew about the 200 hour carb inspection but couldn't find any reference to the carb tear down in either the Line or Heavy and you cleared this up for me. As you indicate, the carbs must be removed for the rubber replacement and while they're off the engine, it would be a good time to have someone with proper Rotax certification (looks like it is Rotax "Heavy") go thru these.

 

Others have asked for a "complete" list of parts needed to comply wth the rubber replacment but I don't think that I've seen one yet. It would be a nice to have an all-inclusive list to refer to when ordering parts. An "optional" list for parts needed if one opts for the carb rebuild would be good to have also.