robertwilkerson

Alum spacer how it sits on the crank shaft I think this is the cause of the black residue coming from the front bearing area the first pic I tried to show were the seal would seat if you did not use the spacer. Sorry for the fuzzy pic's. The problem is depending on which exploded view there is a seal and one does not. Can anyone answer that? Which one is the better of the two. I would like to have a cleaner running engine and the more I think about it being assembled wrong from the factory caused more than normal wear thus the black substance. Thanks for the lock tite trick I tested it on the old case and had to cut the case to remove the front bearing should solve the spun problem. Once the parts arrive I will update you on any improvements I really wish they had not used old coat hanger wire to cast the crank way to soft.

Antique

My Feedback: (4)

The spacer is there so that the front bearing is tightened against the rear bearing when the prop hub is put on the end of the crank...If the crank had a taper the spacer would be un necessary, the hub would tighten against the taper and the front bearing would seat againse a ring or shoulder in the case...If the crank has a shoulder for the front bearing to seat against the spacer is not needed...
The front bearing has nothing to do with thrust when running, the rear bearing takes the thrust...when starting an engine like this the crank can push back against the backplate if a starter is used...Best scenario is a case bored deep enough in front for a second press fit from the inside against a ring in the case, then another pressed aginst the ring from the outside.The outside bearing can be either double sealed or shielded..if shielded it gets lubed from case pressure, if sealed it needs nothing else...

robertwilkerson

Thanks for that input the problem is that the crank is so soft it never seats on the inner bearing race and without the friction will spin under load creating leaks at the inner race and crank. Should this area be lock tiled also? (Front bearing to crank)

Antique

My Feedback: (4)

Anything you don't want to move...I got some green Loctite on a carb throttle shaft once,,,had to use a torch to get it apart...

robertwilkerson

The Stuff is strong! Has anyone had experience with this product it works with the alcohol from the fuel and should improve performance maybe the 91 octane has something to do with the idle.

eclipso

Robert, I really didn't want to make anything personal, I just simply wanted the whole story to come to light. I do not own stock and if I were to do things over again I would probably choose a different engine for the aircraft I have it on. Despite that though this engine has been a great performer, heck it got me through my first ever Imac season and still going. I think it is great that you are taking a step back and a breath and getting things worked out. I think if you take time and care and soak up some info from Antique you will have an engine that will at least give you easy starting and trouble free running. If you are interested I would love to explain how I did the metal reed valve cage and a pulse port similar to the one dogsome did. Can't wait for you to get this thing going again and change your opinion. It is frustrating I know, believe me I got this engine as an upgrade from an SPE 26. That engine started fairly well but I had to replace almost everything and it still didn't have any guts.

P.s. If you want you could likely harden the crankshaft but then it may be to brittle.

Edit: The stuff you show in the picture above should be fine but the issue with ethanol is the mineral oil. No petroleum oil is compatible with alcohol. Synthetic oil on the other hand or at least most of them are compatible and many such as the zenoah or now evolution oils have fuel stabilizers. 91 could cause idle issues but it was probably do to leakage in crank case or reed assembly. Aslo could be timing. I don't know what prop your running but I always get better low end reliability with a larger diameter prop. This engine should run quite happily on a 19x6 if you have the clearance. Iff you don't need the top end you could try one of the silencers from troybuilt that goes into the down pipe and it will give you some more back pressure and it will help your idle and of course quite it down a little.

I went back to the low octane fuel and 30:1 penzoil air cooled and have been using it as suggested by Bowman to break in the new ring and so far I get around a 1900 rpm idle which is fine because I am currently running a 17x8 menz wood prop and I run it to around 8800 - 9000 rpm.

If you ordered a new crank it should fit fine. I really do think you got a dud and I really think it sucks that you had to go and basically replace the whole engine but now that you are doing all the final touches that none of the chinese engine manufacturers do I think you will be surprised at how well this little engine will run. If you know how and can handle a port match and polish then you could do that too but honestly this engine is pretty well machined and it is difficult to port match without some kind of bolt on template, you could change port timing and so on even drop the jug to increase compression but I know I can't do any of that my self so good luck if you have the equipment.

robertwilkerson

Well I put everything back together today, have to admit I have a notchy bearing as it got started wrong. I ordered new ones; Here is the first readings I have after 20 minutes of run. Seems to hold idle around 1890 1900 that is a first even with the notchy bearings. It will hand start choke pop; open flip; rock if no fire... the ring being on the right side of the cylinder had something to do with it you think! Franks rings have a closer ring gap and a little harder material We give it another hour of run time (10 min cool between) see if it smooths out and break in the ring to cylinder til the new bearing come's in damn rear(bearing) got sideways on me and had to pull it in using the crankshaft (NOT GOOD FOR BEARINGS) I might just order another crank to seat the new bearing on it. So here's the deal I am going to eat my words (half way) Engine is good for a newbe's to break into gas. First inspect it re ring then when your are ready to move on buy American. Update with a small adjustment in timing 1-2 (27-26*) advance I have got idle down to 1200 and ran for sometime at that rpm. The bearings being bad has some drag on it and if I can get the new ones in without damage should hold that rpm. If you have this engine put a Bowman ring in it make's a difference. This engine is not yet broken in and getting better faster than the factory one. I might be getting ahead of my self mine has new piston ring and head. I really dont want to port or change this much the tolerances are raw at best and trying to fine tune might be more damage than good. In closing the statement you get what you pay for really hit home with this one. I forgot to mention prop sizes I have been using APC 18.5x10.25 haven't checked rpm but pulls my sig 4 star around like a sport flyer (I like mine a little faster) I have been breaking in with MS raggy 18x6 it looks like two pcs of bubble gum spinning there. I call it my veri pitch prop ( think it goes from 18x6 to 18x2 on the top end).


Thanks for putting up with me
Robert

eclipso

Thats Great to hear Robert ! I am glad things are comin around. I have about 80 minutes on my bowman ring and I can say with out a doubt that it idles better and I took my engine apart last night to mod in a pulse line for carb and there is no sign of any blow-by. My engine is clean which could also be because I am now using the penzoil aircooled to break in this ring rather than the junk lawnboy I originally ran in it, but it is also likely that the tighter tolerance of Frank's ring is to thank for reduced blow-by and better compression. Franks ring takes around an hour to seat but due to the harder material (cast iron)it will take many hours before it is fully broke in. Frank's rings will not expand as much as factory rings hence the reason you can even get away with running near zero end gap and really seal up the cylinder for awesome compression.

Please get a video when you get this thing running the way you like as there isn't much available online for this engine. It is good to help others so we all know what should be done to enjoy this engine or like you stated before that the newbes should check before heading out to the field.

Again I'm glad things are gettin better for you and sorry you had to go through that, you deserved to get a defect free item after you paid good money for it. Unfortunately we have to look over all our rc aircraft items before we use them especially when dealing with arf's or rtf's and even some of our engines. I have never owned an item that was worth any money when it was built in china. I wished I could go to usa only engines and electronics and build a kit from a US manufacturer but it just costs too much.

When you think it is time to get a bigger engine, say a 30cc I would certainly look into the Syssa 30cc. US made and very well built and costs as much as an evolution 26. Rear carb and rear exhuast for slimmer profile and better in cowl install. Just awsome, I am already saving my change for my next 30cc.

robertwilkerson

Have you changed carbs to get the pulse line in? Does it help with the fuel draw issues Man I just spent about 45 minutes getting that rear bearing out that green lock tile close to for ever bond. I have been looking at SSYA since it was intro $449.00 and untested big nut!

eclipso

No change of carb just two 8-32 pressure fittings from dubro a #29 drill bit and an 8-32 nc tap. So far as of the first ground run with the pulse line it has gone a little rich on high end, this is good because I have been having an issue with it leaning out on up lines and such. I already have changed all fuel lines, carb gaskets and diaphrams and even added an atmospheric line to fuse and out of all the many flights I've had, this thing still leans on uplines. I can richen it out to some extent but then all other flight attitudes suffer from rich condition. I don't know, weather is supposed to be good tomorrow so I'll test fly and let you know how it goes. The theory is that these carbs are supposed to have a positive and a negative pulse. These engines only have a negative pulse through the reed cage/intake mani. so my hope is that there will be a stronger and more constant supply of fuel. We will see. Didn't cost but a few bucks and it is the only thing I really have left to do to this engine. I could add a larger venturi carb and a velocity stack, etc.... but I am just going to run it from here on out and just enjoy some flying.

I think next I will get that syssa on here and then put this engine on a smaller lighter profile and just toss it around.

(Edit after flying this thing today it appears I will not be changing a thing it is running great, see post below. Besides according to other threads and forums syssa is having a hard time communicating with customers apparently.)

robertwilkerson

http://www.youtube.com/watch?v=V5gpMMIu1-A I love this breakin in bench

eclipso

Thats funny LOL !

I bet that guy is an engineer, haha. jk

eclipso

Well as promised here is the video of my second test flight today. As you can see the pulse line mod made a huge improvement, it no longer lean bogs on upline, inverted or any other manuever. I am completely pleased with the way this bird fly now. Idle is much smoother and more reliable now as well.

Enjoy...

[youtube]http://www.youtube.com/watch?v=tog19oHA_DY[/youtube]

robertwilkerson

Still running in my new engine, got about 1 hour on it I put a 18x6w on after I had installed the new rear bearing and didn't check the timing started up and threw the prop (glad I was behind it) spinner must have gone 25 feet prop hit the porch and broke the tip another $20 gone! Any way it runs strong the idle still higher than I like might get better with run in (that's even running on a canister muffler) THEY CALL A TUNED PIPE I don't think sooooo! Now after removing from the test bench and attempting to reset timing I have a broken wire in the hall sensor and need a new "thanks for getting it out so fast Mike" yaaa! At this rate should have it on my 4* new year. You know I have had better luck with YS and they say there hard to tune.

eclipso

Sorry all the hard luck mike. I don't know what your running for timing but I run mine at 32* btdc and it idles around 1800 now. I have 1 1/2 gallons on my Bowman ring and I think it is just starting to break as I am seeing a little less spooge and it is idling better. You are probably going to have to do the pulse line mod and be absolutely certain your reeds and reed cage are in good shape. Also be certain there are no air leaks. Did you change that bearing yet?

robertwilkerson

Mike is from Ibecinyou he got the sensor out the same day bout 1hour ofter I ordered it great service. I have been setting timing at 28 and understand 1or2 degrees will not effect it much if your getting a 1800 range I'll try the 32. I should state why the complaint about idle. This is the lowest speed I can get with the throddle all the way back I have removed the screw and spring as it will not be used (servo handles that function) I have checked the reeds no debris and cage is okay replaced all the gaskets and the notchy bearing and will only idle down by riching the low speed till the mid range is gasping for air and slow to spool. Carb might be next I suspect some kind of air leak. It will drop if the I go from high to low (rpm) will drop all the way down to 1100 1250 but then comes back up to over 2000. More breakin?? Maybe? Idea's

captinjohn

It is best to leave spring in place on shaft. Un-hook it if you prefer....but having the spring hooked up does not hurt anything. The load on a servo is not that much with a long arm on throttle. Do more reading and youu will find this out.

Best Regards Capt,n

robertwilkerson

Thanks for that information but that is not the problem as I have left the spring in place but removed the tension. I removed the idle adjustment screw and associated spring not the one on the butterfly shaft.

eclipso

Sorry double post.

eclipso

Its good to leave tension on the throttle spring in case you loose the throttle linkage. The idle issue is due to the lack of fuel supply, you are compensating for it by richening the low needle to much. My engine never idled low until I did the pulse line mod. This happens because you don't have enough fuel to lean out the high end. Most people think that the low end changes the mid range but it actually has very little effect unless the high end is already to rich. Low end needle is for idle and transfer but both needles are needed for mid and high but high is mostly the high needle. If you notice you can richen the low needle until mid burbles but high will go to lean if you lean it out any more. This is the problem I had, it wouldn't idle low but I contributed that to small light prop but now that I fixed the fuel supply strength it runs like a DA.

robertwilkerson

I got a email from Frank Bowman and he writes there is some problems with the reed block not allowing the reeds to seat properly repair consist of removing the reeds flat surface sand lightly both sides of the cage reinstall reeds. I had a hard time finding some Penzoil air cooled so ordered some on line I can post the site for those interested.
Bowman suggest all Dyno for the rings to seat. The pulse line is getting more of interests let's see how these corrections go and maybe we will talk. Maybe take a drive down. Just for back up I order another reed block why not every thing on this engine has been something wrong. Let's see what next week postman will bring me. I ordered the ring for the 50r too! looking at the 50R carb plate (the side the pulse line is on they use a 90 at that fitting may clear the beam mount better.

eclipso

Now we are talking Robert. These reeds are ok but that reed cage is crap. Like I said in earlier posts I had the center supports of my reed cage just fall out. I would get an rcgf 26 reed cage because it is aluminum it is not a hard mod. Do you know if that Mike guy carries the gasket set for this engine? I had to make my own gaskets but I would like to get a set of the originals now that I have everything set the way I want it. I have to admit I fully agree with your frustration and I did have to go quite far with this engine but the mods I've done aren't any different than the mods I would do to a dle. I only have time, a ring, and a new reed cage and reeds in mine but I too would be upset if the bearings faild and the engine was assembled wrong. Anyway at least things are looking up Rob after these things are done you will get to run the engine alot but then your airframe will probably start to fall apart like mine is. I hate that the airplane can't just run without issues for say 100 flights then change fuel lines and fly again, always some covering falling off or cowl screws falling out, etc.... maybe someday I'll have a solid plane and I will have my way. If you ever get around this area just let me know and we'll take a look at things and maybe get out to the feild.

robertwilkerson

Hey if the covering doesn't fall off how would ever get the thrill of the iron and blower. You know I have been searching for a carbon fiber reed and found some on a mini bike shop my concern is will they fit? You mentioned that your reed block is plastic not the cage but the block. Mine is made of aluminum are we talking the same block. Raven RC has the complete assy Ernie has it all listed and priced for ease of order. Mine looks like this one RCGF bp hobbies there is a dark spot along the top is that were it broke? I have some marks on mine in that area and is caused be the starter pushing the con rod against back plate and top of cage. This is why it is important to seat front and rear bearings when they spin in the case allows the bottom end to much end play starter force just makes it wear faster.

eclipso

The picture that is circled is the insulator block and it is made of phenolic. The one in this picture is an rcgf insulator and is unfortunately very cheap and porous, when I tried to mod this piece is just fell apart. The other piece is what I refer to as the reed cage. This reed cage is better than the crrc gp26r because it is metal. I don't know if any of these crrc engines come with the metal cage or not but mine didn't it was phenolic with a phenolic insulator. I was able to mod the crancase back plate and the original phenolic insulator to accept the rcgf aluminum reed cage. The new aluminum reed cage does not extend into the crankcase like the original did so I don't have to worry about the rod, bearing or shaft hitting it. If you are interested in this mod I would be happy to help. I hope you can get the bearings and shaft seated completely so as to avoid anymore internal damage.

Oh one more thing. If you look at this reed cage it has screws holding the reeds. In the gp26r it has a rubber boot type gasket that holds them in place but the problem I found is that the rubber boot doesn't give enough tension to make the reeds as tight as they should be.

Dave

robertwilkerson

Mine is the same as pictured no rubber boots just small screws a new one is on it's way pict's in the bag , I have flat surfaced with 600 grit. Here is what I think it needs the screws hold this reed in place does nothing to keep them flat and the reeds do not always close completely just my feeling and no test to proved that it exist. I have been doing some research and carbon fiber reed have a stiffer surface this would solve that issue. My problem and hoping there is some one who knows where do I get one of these and how do you know it will fit. I found some on a scooter store but not sure if they would be a drop in replacement. The bearings will not be an issue as the green locktite is so strong I will have to replace the case if I need new bearings (not a bad idea anyway) being locked in place the end play is limited to starter pressure and if the induction problem gets resolved will not be using it.