G. Bradley Note about highest time R2300 engine

[984dm]

Hello builders and flyers with interest in the Revmaster engine line,

I have been in touch with Glen Bradley over the past few years regarding his Revmaster 2300 engine he's flying behind in a Thatcher CX-5. Glen has been a valuable resource for me, with lots of experience and information. He has over 800 hours on his engine now (probably the most of anyone). I am including his recent report in entirety just in case you were not able to open the link that Wes attached. Glen gave me permission to share this information with the Sonex group.

Dave Misner
Sonex N984DM (work in progress)

Glen's report:

"GLEN BRADLEY cx4n5guy@gmail.com
Aug 13, 2019, 1:08 PM (17 hours ago)

Since I apparently have the high time R2300 in the world I thought it would be appropriate for me to share the operational history of my R2300.
Here goes:
I have not included all the oil changes and valve adjustments and head torques as I have done valve /oil maintenance about every 35-40 hours and head torque every 100 hours.  No significant head torque issues were found- only 2 bolts at 100 hour point and the need almost non-existant. 

100 hours - new oil cooler/ leak in second row of fins
281 hours - new oil cooler/ same issue
 I found that my engine oil pressure was WAY too high by checking using a separate gauge well over 100 psi and since it had always been that way my panel gauge was nearly always pegged and I didn't know that was abnormal for Revmaster engines. I reset the oil pressure spring to 70 max/ 55-60 at cruise and no more problems.

360 hours- my aluminum pushrods started to collapse giving me valve clearances from 20-48 thousands.  I have pictures of one steel tip at about a 25 degree angle.  The engine ran fine but when I checked the valve clearance at oil change I found this issue.  
Joe provided new steel push rods and I installed them thinking the problem was solved and for many hours it seemed to be. The check at 500 hours had shown no sig wear but from 500-540 hours they had worn approx. one thousandth per hour for gaps of up to 45 thousands.  I concluded they were not hardened deeply enough.  Joe checked their hardness and found that to be the case.  Joe had no replacements and didn't know when he would so I went to AMAZON and bought a set of EMPI chrome moly push rods - about $60-that one cuts to length. The machine shop I use cut them and installed the tips to length for about $40, and I was soon back in the air.  I have seen no significant wear from that point on the  800 hours. I have to adjust maybe 1m or 2 valves about a thousandth every oil change.  Last oil change no adjustments were required.  I set the chrome moly valve clearance to 5 thousandths.  

Approx  450 hours --A strong electrical smell developed during flight and continued for until I landed/about 7 min.  I had had an ignition coil burn out long ago - super easy fix...but this smell was different. After some searching I took the CDI cover off and ohmed out the STATOR.  It was bad- burnt to a crisp.  Joe did not have any in stock so a month or more went by and I finally got a new one. Installing it meant removing the engine---not fun. The install of the stator was quite easy once the engine was removed.  
In the process I learned a lot about the charging system. Revmaster wasn't sure what had caused this issue but they decided that it may have resulted from running BOTH  alternators at the same time, thus overloading the battery with the excess current.  They also decided to recommend a wet cell battery....I had just bought a new Odyssey battery a few days before even thought the 5 year old battery worked fine.  Anyway, I set up a three way switch  ALT 1    OFF    ALT 2 and have had no problems since. 

550 hour issues>>>>
at 550 hours my engine developed an oil leak. at the cylinder base which is sealed to the case by RTV.  It gradually leaked more and more and finally got pretty bad so I pulled the cylinder.  The hardest part was, of course, the baffling. 
Taking the head off loosened the other cyl base so I took them both off.  The valves all looked good and compression was still very high but it was so easy to pull the cylinders I decided to pull all of them and have the valve seats recut  (triple cut) and new valves too since it was so easy and inexpensive. The big clearances had beat up my valve adjusters a bit and rather than resurface them I just replaced all of them.  So my leak turned into a complete valve job.  That way I wouldn't have to do any work for a long time.  Total cost of materials and machine shop was $380.  I have had zero issues with the valves and pushrods since and almost no adjustment of valves since then.  

600 hours 
I began to have a slight miss on one of my 4 ignition systems (CDI)   The miss got more prolonged over the next 20 hours or so and got to the point that ig system would not work at all.  Seemed to me a wire was gradually losing contact but that was just my wild guess.  I checked all the ignition connections, even those inside the CDI housing, and found nothing. I spent over a week looking to the issue.  I ohmed out everything.  I ran all the ignition diagnostics that Joe prescribed.  NOTHING.  Finally Ralph, Joe's engineer ( a true genius and a gentleman) said it must be the CDI board.  I talked to Dwight Hoover who had had issues with his board and his friend, an electronic engineer,  had made up a new board for him which looked superbly done.  Dwights old board was embedded on what looked to be cereal box cardboard. No kidding.  I had to order one from Joe- around $400.  Anyway, Joe said I had to sent the CDI housing to him so he could embed the new board.  A couple of weeks later I get my new installed board and it did truly look good- very professionally done.  I installed it and.....it was NOT the problem.  So here I was out of flying for over a month and over $400 and no closer to the finding the problem than before.  A friend I had taught to fly 35 years ago came to town to visit and he  is a superb A&P.  Awesome. He and I spent a day going back over connections etc and other possibilities.  No progress.

He left the next day and I went out to the hangar determined  to find the problem.  I literally looked at EVERY connection again, even up INSide the connectors for ANY abnormality.  In a few minutes I saw that in one of the Mollex connectors one tab was inside the housing was pushed in a very small bit less - maybe 1/8 inch-than all the others.  I knew I had found the problem.  I got needle nose pliers and pushed the connector  IN to match the others. This had been hidden up inside the connector and almost impossible to see.  One had to look UP INTO the connector and be very precise at judging the distance the connectors were pushed in.  When I heard the CLICK I was expecting I knew my problem was solved.  It was.  The engine has run perfectly ever since.  NOTICE-- the engine ALWAYS RAN FINE with al ignition systems on- it has never missed a lick in the air.  

Writing this makes me think I have had lots of issues but remember it is 800 hours and the costs have been pretty minimal, including $400 for a CDI board that wasn't needed.  Overall I LOVE the Revmaster R2300.  It has never missed a lick in flight and starts easily every time  It clearly puts out way more HP than one would expect and, to this day, does not need any oil added between changes at 25-40 hours. My plugs don't need changing at 200 hours but I change them anyway- they are cheap.  I use approx.  70% auto fuel NO ethanol with  30% 100LL I have never had a plug fowl.  

I may be buying another R2300 soon and If I do I will immediately:
Set the alternators to run only ONE at a time.
Replace the push  rods with EMPI cut to length at the first oil change.
Make sure  my oil pressure is not too high. 

This should prevent nearly all the problems I have had.  I hope this info may save some of you most of the problems with your R2300.

Glen

--
Glen Bradley
Pensacola FL
850.816.4868"

“The views and opinions expressed herein are those of the author in his personal capacity and do not necessarily reflect the views of Thatcher Aircraft, Inc. My comments  should be taken only as those of a good friend of the company and the pilot of the first CX5.. Your aircraft may, for many reasons, fly and perform differently- especially due to differences in build and piloting technique."

[WesRagle]

Thanks Dave.

BTW, Glen is running a Zenith carb on his Revmaster isn't he?

Wes

[flyguyeddy]

Pretty sure he is running the 14998 zenith