shane55

My GP26R had a big end bearing failure yesterday after only 6 hrs run time. The conrod destroyed the crankcase and roller pins damaged the piston and cylinder. I was running on straight oil at 30:1 as the instructions state not to use synthetic during break in. I had a similar event with a gf26i about 6 months ago when the small end bearing failed also causing extensive damage although that engine had about 50hrs run time and was running on synthetic at 30:1.

I am wondering if the roller pin bearings on these engines are a weak point, the cage that holds the rollers looks very light. Its probably the worst part that can fail on account of the pins getting thrown everywhere, like a bomb going off in the engine! The big end bearing does not appear to be available as a spare on its own, you have to buy it with the crank and con rod.Or is it that the conrod and crankshaft should be replaced as well after this kind of failure even though there is no visible damage Im not sure about the cylinder damage, usable maybe? After a good run initially with the gf26i, I am now getting disillusioned with CRRC engines.

Is using non synthetic for the break in a fallacy? There seems to be conflicting opinions about this. Some say the piston ring will not seat properly with the cylinder if you dont break in with straight oil while other people say you can break in on synthetic, the seating process will just take longer. Im wondering if the better lubrication of synthetic oil may have prevented this failure.

I dont think there is any counterfeiting of CRRC engines taking place like there is with DLE. I bought this one from http://www.goodluckbuy.com/index.php...oduct_id=84425

1QwkSport2.5r

The whole synthetic vs. mineral oil debate has raged forever. Each oil has its pros and cons, some are better than others. Unless your needle was way too lean, I doubt the oil was to blame here.

I use use both oils depending on what's in sale. Never had a gas ignition engine fail, ever, even using cheap walmart oil.

Gizmo-RCU

My Feedback: (27)

With my limited experience with CRRC engines, 3 or 4, there always seems to be a problem. They are at the bottom as far as quality in my humble opinion. Had two 40cc Kit engines that never really sealed right and the ignitions failed rather sooner than later.
Also a 26cc like yours, ignition failure from the start, missing gasket under the carb...............ran ok after that. Could have bought a DLE for the extra cost of the ignition!
I would not try and save what you have, the cost should go into a higher quality replacement. I am afraid that with CRRC you get what you pay for, with that I suspect I have offended some "die-hard" fans?

Who would want to copy a CRRC????

shane55

I probably will not buy another CRRC either, The GF26i did serve me fairly well for a few yrs until the small end bearing went and damaged the piston, then the big end bearing failed shortly after although a lot less conspicuously, The engine failed and I found some pieces of metal embedded in the cylinder head. I couldnt figure out where they had come from until I looked closely at the big end bearing which is permanently connected to the conrod and crankshaft in the GF26i making it difficult to inspect properly. I noticed that the cage was damaged even though none of the rollers had actually broke free. The engine probably would have ran for another few flights with the damaged bearing until it failed completely

3136

+100

Shane could you show a pic of how the spark plug looks.

shane55

Heres the plug, Normal, AFAIK

irocbsa

My Feedback: (12)

Wow, sorry to hear about your bad luck. That is quite the extreme failure.

psgugrad

My Feedback: (2)

Thanks for posting. ...I was considering this engine myself and I'm glad I saw this.

shane55

considering how light the metal is in those roller bearings, big end and small end, they look like its only a matter of time before they let loose. Once they do, its the loose bits of metal that do all the damage. These are the only engines I've worked on, perhaps the roller bearings are similar in all engines, they look like they are definitely a weak point.

shane55

You would probably be better off to go for a DLE 20, probably just as much power,lighter, although the auto advancing ignition is a bit of a nuisance

irocbsa

My Feedback: (12)

The latest DLE20s have an ignition with an improved spark strategy. The previous module would just step from one level of advance to another which obviously caused some problems. The latest module has a bonafide advance curve in it.

Valley View RC also makes a great little 20, although I'm not sure if they will ship to Ireland.

RCGF is a good option as well. Their 20 has had good reviews on this site.

Either one of those engines should get you the reliable replacement that you need. Best of luck.

Gizmo-RCU

My Feedback: (27)

I have a VVRC 20, they come with RCXL ignition out of the box. It runs as well as my friends DLE 20. Worth the consideration if the price is right?
Something of note, many of the bearing failures I have experianced are the cheap Chinese versions, guess you would expect that in a Chinese engine but I have found them in some of the better Japanese engines.
I take my old bearings to the Bearing Supplier I use and they verified where the old ones were manufactured. They do not sell Chinese bearings because of quality issues.

shane55

I hadnt thought of doing that, using bearings from a different source, I thought the sizes/tolerances might be out if you didnt get the oem. But I presume they are standard sizes, are they? CRRC only seem to sell the big end bearing for the gp26r as part of a kit with the conrod and crankshaft. Is this just for their convenience or is it recommended that the conrod and crankshaft are replaced as well after the bearing fails?

Gizmo-RCU

My Feedback: (27)

Just take in your old bearings, they will mic. it and match, no big deal and much less expensive. The rod is part of the crank assembly and is a pressed fit as I recall? You are stuck with the big roller bearing.......the outter beaings should be replacable?
Afraid you are going to have to replace the rod and crank as one. Combine that with a new case, head and piston, gaskets, ect. No deal here I am afraid?

I have an XYZ 26 crash victem in much better condition and not worth salvaging.

irocbsa

My Feedback: (12)

Agreed, sounds like a new engine should be in your future. Are you determined to make the CRRC work as a way of learning about engines? That's great if you are, but if not, I sure wouldn't give my business once again to a manufacturer whose engines catastrophically failed twice!

shane55

I could repair it for about €50, It cost €140, haven't decided yet if I will repair it. On the GF26i the crank, bearing and con are press fitted together, they are separate parts on the gp26r athough they're not available separately.

shane55

Which module is that, I have the A-01 and A-02, Is it called A-03 ??

irocbsa

My Feedback: (12)

Was the old module a #4? Seems to ring a bell. I think the newer ones come with a better module as I mentioned, but you might want to check on that. Maybe someone else can chime in to confirm or refute?

shane55

I have 2 versions of the #4 module, A-01 and A-02. The A-02 has a higher working voltage, 8.4V as opposed to 6V with the A-01. I have not used the A-02 yet but I think I read that the only difference from the A-01 is the operating voltage

irocbsa

My Feedback: (12)

Maybe try a module from a different 20cc or one of these:

http://www.rcextremepower.net/ignitions.html

I have a couple of the RCXPs and they work flawlessly. As an added bonus, they're only about 75% of the size of the RcExcl.

shane55

I replaced the #4 module on my first dle20 with a standard rcexl module and its working fine. I have lately got a 2nd dle20 that came with the #4 A-02 module thats going into a seagull C152. The first dle20 is in a H9 corsair and the sudden rpm drop during approach was making things difficult. I might try the C152 with the #4 module and see how it goes, it will probably handle better than the H9 corsair. Its kind of a pain to buy a new engine and then have to get another module for it.

Had not seen The RCXPs before, A little expensive with international shipping though, $75 shipped. Got the rcexl for $45 shipped from china

irocbsa

My Feedback: (12)

That's a good deal. Go with the standard RcExl module if you can swing another one.

ahicks

My Feedback: (2)

If the module is showing it'll handle 8.4v, it's one of the newer style that don't have the single step timing curve.

Would just like to mention that the idle hang/drop could be 2 different things. 2 completely different, unrelated issues. One is heat/idle mixture related, and that issue is just as common a problem as the single ign. timing "step" at 2400 rpm (or so) on engines with idles set too high.

There's a lot of us flying on the original modules (with step) that have been able to figure out what's going on to the point we can tune around both those issues! Of note is that the temp/mixture related issue can occur on any 2 stroke engine - not just the DLE 20! I recognized the "high idle hang" first while riding a 170hp 800cc 3 cylinder snowmobile 15 years ago? It was doing the EXACT same "high idle hang" thing, for the same exact reasons these little guys do it when incorrectly tuned!

All that said, couldn't agree more with the idea that the newer modules allow for simpler tuning. Also agreed, best of the bunch being the new Rcxp. -Al

irocbsa

My Feedback: (12)

Great advice Al.

You might want to delay your return to Michigan by a few weeks. It's still miserable and freezing up here.

JRgraham

My Feedback: (1)

Not to add salt to the wound, but really..? GoodLuckBuy . com ? sounds like a risk right there in my little brain.