Failed first engine start

Bob, 

The injectors seem like the most probable cause.  The way the coils are arranged, you would need to loose all four ignition coils to fail both the top and bottom plugs of cylinders 2 and 4. While it’s true that you would need both injectors clogged to have a totally cold cylinder, I think that is more likely.  You may also have one of the injectors clogged on cylinders 1 and 3 and they are limping along on one injector.  There are injector cleaning services, but Rotax would say replace them all. Maybe you could have them cleaned as a test, and if that solves the problem you could then decide to replace them. At least it’s a lot cheaper test than replacing them and having that not be the problem.  

Hi all

First, storage over 2 years is extreme.  The auto fuel used at the hot test by Rotax will gum up in the injector nozzles when left that length of time.  The first thing is to pull all the injectors and take them to a professional injector cleaner.  They can be cleaned without much trouble.  The issue here is you need to have someone familiar with the Rotax iS fuel rails and how to handle the wire harness.  Don't do this on your own without training is my suggestion.  

For Jeff B, I doubt that the injectors will need replacement.  The ones Rotax uses are very high end and very well matched, they are not from a spare parts producer budget company.  If you are worried you can get the new O rings for them, they are listed in the parts manual.  You are correct in that is very unlikely to be ignition coils in this case. 

Cheers

RW,

I only meant that there is not an official injector cleaning procedure in the Rotax documentation.  There is a visual inspection only.  That said, we are in agreement about the injector cleaning.  

Jeff...I know and agree with your view.  We were promised a section on cleaning the injectors many months ago.  Indeed it has been requested from years ago.  Some at the factory believe we are too dumb to carry out such a sensitive piece of work. (?) I don't know but keep pushing for an inclusion in the heavy manual.  At this point you are just fine with any experimental, go ahead and do it.  If it is certified or SLSA (almost certified) then we get into a big grey area.  If this type  of work was found in AC 43-13 current edition we could do it, yes it is that common I believe, so perhaps I am pushing the wrong people.  

Perhaps we have to lobby the authorities and not Rotax I think.  Cleaning a fuel injector is not difficult.  

Cheers

I think what I'll do is just take the engine off and ship it out as I'm unable to find anyone in MN who feels qualified to work on it at the hangar..

Now I've got to find some crate-building plans.