CRRC Pro GF26I

[bosshoss]

Yikes!!!!!

I hope mine is OK, is Jim from Western Hobbies getting you a seal??

[hardtop351]

no mike...i have gone and gotten my own seal and i also have got 2 new bearings....thses bearings feel very gritty to me and so while it is all apart i will replace them. and yes RCIGN1...i will be using the bearing type with a seal in the front housing.

will post more photos as i go

cheers
craig

[hardtop351]

ive spent most of the night here still trying to start this engine. and it STILL wont start. its got 2 new bearings on the crank AND a new shaft seal at the front and STILL no joy in getting it to run.

i think the CDI unit has got something to do with it....i hear high voltage sparks being made even when the crank isnt turning. i tested this theory by using a test plug that i have and found that the CDI unit aint working as it should. it still sparks as it should but not when you want it to.

also guys....DONT be heavy handed in tightening up that little spark plug either. ive broken 2 plugs now. the thread separates from the body if you lean on them too much.the second one being an NGK plug.

i have taken some pix and will post them soon

cheers
craig

[TrikeFlyer]

Hardtop there is an issue with the EI circuit. With everything hooked up ready to run, listen very closely to the EI box and you will hear it arc inside. Sounds like snap of spark at plug but inside the EI box. Yet when you plull the plug out it will spark normally at the plg and not inside the EI box.

Drove me crazy until I substituted an EI I had bought for my Ryobi conversion and still couldn't get it to run untill I turned up the idle quite a bit. It started on the 2nd flip and now starts every time on 1st or second flip.

Now have over 3 hours on the engine and ready to transfer to my Laser 200. I will now change from the 32:1 Penz for break in to 40:1 Motul or BelRay synthetic.

Just about ready to do RPM test with different props and then do maiden flight in the Laser next week end.

[hardtop351]

yeah trike that is what happens. looks like another dud CDI the same as the one i had for my GF45 engine.

while the engine itself is quite well made...it appears that the "bolt on" gear is what's letting the whole show down. my engine is currently still in pieces awaiting me to cut some new gaskets for it.

cheers
craig

[TrikeFlyer]

Yah, bummer Hardtop, that is why I didn't tear my engine dow. No replacement gaskets and I didn't want to have to fabricate new ones.

The GF26I does run very well. Has immediate throttle response/ transisiton to high RPM. My RPM tests should start tomorrow when my new test sand is completed. I used the wrong materials constructing the current one and I am afraid of results like the DL50 accident.

[nicetie]

FYI: Those engine standoffs sell 4 for $30 at the LHS and over the internet!

Ken

[CRRCproUSA]

Hi Testers,
Yes, I have done extensive testing on this engine now and the original CDI. I have also been working with the factory on resolving this and they are now going to do more testing because they are not having the same results as we all are having doing our tests. I think alot of the no-run issues all of you were having are 100% ignition related and nothing else. Also, the bearings are an open design on these engines for a reason - less drag. A bearing with seals on both sides will decrease performance by adding surface drag. Nothing wrong with this seal design. Also, after testing the CDI with the factory and many discussions - it is correct that these ignitions are indexed at approximately 40 deg BTDC to provide auto-advance. This is contolled by the initial delay within the auto-advance circuit which will bring the advance back to a manageable level after the engine is started. This does work for running but it will make for difficult starting - it is one of the design points being discussed. The next point discussed is the determination of HV leakage within the CDI circuit itself - there is a fundamental transient HV problem that I cannot trace because the circuit components are potted and I cannot see them (although I can hear the spark internally). So, as of now the engine is running like a swiss watch on my test stand with an alternate ignition providing about 8580 rpm on a 16x8 Xoar.

Sincerely,
Jim
Western Hobbies

[hardtop351]

jim....

yes i agree on the ignition issues. and its good to see that the factory is listening to what we are finding out. if you look in the photos i posted you will see the bearing in the crankcase halfs. these are new NSK bearings with the seals removed. except for the bearing in the front....it has 1 seal removed while the other is still in place to help seal the crankcase off.

cheers
craig

[nicetie]

Jim, Are you saying the initial setting is 40 deg BTDC? This is the way I understood your statement! Please explain. An initial BTDC settting would normally be about
5 deg and advancing with RPM (or in the case of mechanical advance) to 32 deg BTDC or so if using 94 octane. 40 deg BTDC at start would tear off your fingers!
Ken

[hardtop351]

WELL WELL WELL!!!!!. i got my engine running!!!!! admittedly it was running on my fuel the i use in my GF45....but i still got it running.

in the photos you can see 2 CDI units...the silver one is the one that we all know is faulty. the small black one is the original CDI unit from my GF45 engine. i hooked it all up and tested it on the bench first to see if it would work. it did.

i cut some new gaskets and put the engine back together and bolted it back on my test rig. the fuel is 40:1 methanol/synthetic oil. it was the only fuel i had at hand lol.

anyways.....i primed it up and gave it a flick....it burped!!!....finally it started and i tuned it a little and gave it a few quick squirts to full noise.....what a FAST transition!!!!!!! currently it has an APC 16x8 prop...but it was just to get it all going.

i have a smile from ear to ear right now....i finally got it to work and now can say for sure that yes its the silver CDI unit thats at fault.

more to come.......

cheers
craig

[TrikeFlyer]

Nicetie, I also found the initial BTC timing set at 40 degrees and questioned whether that was correct. The factory said for this particular EI it was.

The way these ignition modules work (EI) is they do not advance at all. They RETARD the spark by about 26 degrees (depending upon the particular EI) when you first flip and start the engine.

Therefore you set the BTC timing at where you want it for when the engine is running max RPM. When you start the engine the EI retards the timing so you can idle the engine down and it will be smooth due to the retarded timing which will be the initial BTC setting minus the degrees retard of the EI which is usually 2 -6 degress..

As you advance the throttle, the EI retards the timing less and less as the RPM increases until the timing is back to the initial BTC timing.

Some EI's retard the timing more than others so you have to set the initial timing accordingly to get the BTC you want or that gives to max RPM.

Hope this clarifys the timing issue.

Trike

[bosshoss]

I can't wait to try the new ignition that CRRCPro is working on. Mine is going back to the factory. There are quite a few people I know that want a small gasser, and after seeing mine in my EF Yak they are very excited.


So am I.

[TrikeFlyer]

Same here BossHoss, many of my flying buddies are waiting to see how well the GF26 flys my Laser this next weekend.

Here is the plane it is going into tomorrow night after I do some RPM tests tonight.

Trike

[hardtop351]

hey hey all....

just to give some figures so far with my rough running engine...

these figures were taken with the engine using methanol/synthetic oil...

top rpm....8700rpm
idle..........2200rpm
prop used....Master Airscrew Classic 16x10

while this engine is working...it vibrates a LOT!!....i think this has a lot to do with the timing being out and using different fuel to what the timing is set at.

i will try petrol fuel in the next day or so but will leave the timing where it is for now

cheers
craig