FNQFLYER

Question for the Gas people.  KLGME8 plugs could they be considered suitable to replace the Saito plug in the FG range of engines, specifically the FG14, 20 and 36?
Also any one had any "exposure" to the new gas twin yet?  I have money burning a hole in my pocket at present and it looks like a good way to dispose of it.
Earlwb  seen internals like that a lot, for all its worth I use my covering heat gun to warm up the crankcase to a point where I can't touch it with my bare hand then go the bearing extraction route, though over time we have found that the crankcase "expands" a little (several bearing changes that is) so then we use a little Locktite bearing lock to secure the bearings from turning inside the crankcase.    

earlwb

Thanks w8ye and fnqflyer.  
Yeah I had read about the fact that the aluminum crankcase can expand and not shrink back down after it gets heated up too much.
The first I read of it was some guys who welded on their crankcases and then having the problem where the bearings were loose afterwards. As they didn't take precautions to help keep the crankcase cooled down during the welding.
Then there were a couple of guys who overdid the propane torch heating method a little too much, and then the new bearings were loose.

kevinkenny

I am looking for some advice. The 1/3 cub forum seems to only talk to the old boys club not interested in new bee's. I have a 50CC engine and had to get a large internal exhaust which needs the muffler box to be insulated. Any suggestions? Kevin

kevinkenny

for got the pictures of the exhaust in the 1/3 cub. Kevin

w8ye

My Feedback: (16)

The spark plug in the FG30 and FG36 Saito engines is the NGK CM-6. There is actually no replacement for it except for some Iridium plugs sold by RCEXL

The FG20 and FG14 have a 1/4"-32 spark plug that has a Saito brand on it. The spark plug cap does not fit the 1/4-32 sold by RCEXL or the other company in the USA.

earlwb

usually for the canister muffers, they have a ventilated box surrounding the muffler. You want a air gap all the way around so that the muffler case doesn't touch anything nside the plane, except for the mounting brackets. You use something like 1/64" inch plywood to form the box with. Now you can also line the box with some aluminum foil to help reflect heat away from the insides of the plane too.
I think this article here will give you ideas for it.
http://www.rcflier.com/quiet/stf/ins..._canisters.htm

kevinkenny

Thank you Earl. The article was very instructive and helpful. I plan to stuff the box with Fiberglass with a foil back. Its just very difficult to make the side walls out of wood with everything already in place. Thanks again.
Kevin

FNQFLYER

w8ye, thanks for that, will pass on the data to the various people that made the inquiry of me.
Earl, re the exhaust remember outlet capacity air from the cowl should be twice that of the inlet otherwise you will have overheating problems, as our local hobby shop guy found out a couple of years ago, all went well will model until new exhaust fitted restricting outlet air big o/heat props actually fixed in the interim by restricting the inlet air.
Re the heating of crankcases, we usually stay away from propane torches, one guy as I was reminded had a Bundy (rum) event while doing that with an OS and had t purchase a new crankcase cause of the hole on the side.  Not a pretty site.  

tiffitech

It happened to me while I tried to repair a broken Crankcase of an SuperTiger ST34G. The entire crankcase growed somewhat but it was defective anyway.
The Carb throat was broken off on the rear side. There is not much that you can do for cooling the crankcase if you want to solder that.

Regards,

Holm

Rudolph Hart

Rum can be dangerous fnq,buy yourself a carton of vb cans and a handrolled havana then relax mate hi craig hope the shoulder is good how's the house?

Indiomike

My Feedback: (5)

Engine is a Saito 82a. It runs well at high end with just a little vibration. Low end is horrible. Vibration is huge and the engine sort of makes a loud knocking sound. I've adjusted the low speed needle both in and out but the vibration and knock is still there. The low speed needle is at about 2mm below the plastic housing. Going in further causes a rpm drop. Going out seems to make the knock and vibration worse. I did a valve adjustment but the problem persists.

Help please.
Indiomike

w8ye

My Feedback: (16)

It might have bad bearings? Have you felt of them?

earlwb

have you had the engine apart? sounds like maybe the camshaft timing is off more than one tooth.
Do the bearings feel Ok, when you turn the engine over?
what fuel are you running in it? How much nitro, etc?
Did you put in a new glow plug, if so, what type and brand of plug?

Indiomike

My Feedback: (5)

I don't know how to check the bearings. Do you wiggle the prop shaft to see if there is any play side to side, fore and aft, or top to bottom? Please explain. The fuel is Byron Performance blended 15%. Don't think it's the fuel as I also have a Saito 100 in another plane and this same fuel runs it perfectly. The glow plug is the one that came with the engine. I think the glow plug is okay as the engine will readily start. It is just extra rough running around idle rpm. The engine has about one hour total run time and runs well as long as the throttle is about one third open or more. Top end seems really good.

FNQFLYER

Old Fart the XXXX brewery is still in production (using clean water not river water) so why would one want VB (known in some places as young ladies water)
Re the checking of shaft bearings I use the tested method for checking racing YS bearings, put prop on engine secure engine apply hand to and grasp prop (with 2 hands) and attempt to move from side to side and up and down.  On YS any movement and no more racing but still fly gently for rest of the day with Saito in normal use very little movement continue to use "gently" but monitor anu appreciable increase remove bearings or if you continue to fly save rapidly for new engine. 

Indiomike

My Feedback: (5)

Here is a bit more information on my 82a. Yesterday afternoon I took the engine out and dismantled the carb to see if I could find anything there that might be a problem. I did not find anything amiss there. When I did the valve adjustment I removed the glow plug and used a toothpick in the hole to determine TDC. I was able to wiggle both rocker arms slightly so I am pretty sure I was at the proper position to do the valve adjustment. The exhaust side (side closest to muffler) was much too loose and require readjustment. The intake side tested proper.

The engine is installed into a Great Planes Matt Chapman Eagle 580. The prop I'm using is a wood 13x7 and has been balanced before use.

Indiomike

My Feedback: (5)

Just went out and ran the engine again in the plane. Engine idled at 2600 rpm and although a lot of shaking, it held idle for over a minute. I'm beginning to wonder if the problem is that the engine just needs more running time to break in. I'm also thinking the noise I'm hearing may be a resonance coming from the model itself. Could those two items together be the culprit?

blw

My Feedback: (3)

Indiomike- this may be the time to adjust the low speed leaner with extra care. Small adjustments, very small. If you adjust it to get a lot of smoke then it is rich.

FNQFLYER

if the engine is still in the a/c check the engine bolts holding it to the mount, and tighten if required, if tight check the mount for cracking, especially if it is glass type, and then check the bolts holding the mount to the bulkhead, then the bulkhead (firewall) it self for integrity.  If all ok try another prop if trouble still persists could be bearings, bent crank shaft or bent / broken 9partially) rod or gudgen pin (hold rod t piston 

Craig 01

G'day Old Fart,shoulder is coming along ok and the house is fine,luckily for us we are on high ground.

Hobbsy

My Feedback: (102)

Two things tell us that the LS needle is too rich, the high 2,600 rpm idle and the shake. Re-set the LS needle with the HS needle at absolute peak and as BLW said use small changes. Saitos will run and idle well when set very rich. Another clue to a rich LS needle is poor fuel economy. Use a tach to find the High Speed Needle peak. This should all be done on a test stand.

Indiomike

My Feedback: (5)

SUCCESS REPORT

First of all I want to thank every one who offered advice. I took it all to heart. So..... I removed the engine from the plane to run on a test stand. While the engine was off I inspected the firewall and engine mount for integrity and it was fine. After a short warmup I went to full throttle to get the high end set. I was good there as only 2 clicks in caused the engine to sag a bit. Throttled to idle and began tweaking the low needle. I found that it needed to go in (leaner) about 100 degrees or about a quarter turn. I have a Glo-Bee tach and it jumped around a bit but I was able to get the idle to around 2250. The tach would jump all over the place between 2200 and 2300. Transition from idle to full was very good. I measured how much the low needle screw head was below the plastic housing and it was about 3mm.

Thanks again to everybody for your help. Hobbsy's advice on the low end proved to be the problem area.

Happy flying.... Mike

NM2K

My Feedback: (14)

It is good to see you back again, Hobbsy. I hope all is well at your end. Or as well as it can be, considering.


Ed Cregger

earlwb

It was sort of a pleasant surprise when I test ran my old Saito 80 engine after replacing the crankshaft bearings, and I got the cam shaft installed correctly the first time. I didn't have to pull the cylinder/head unit off a couple of times to get it back on correctly.  Anyway, that was nice that I got it the first time. I guess I should have bought a lottery ticket. Anyway the engine is back in the airplane now and ready to go flying again. I guess I could go and clean the gunk off of the muffler, but what the heck, it works. It is sort of a puzzle as to where the oil is coming from to get on the muffler in the first place. You wouldn't think it could ooze oil from different places that would get on the muffler and exhaust pipe.

NM2K

My Feedback: (14)

I'm glad that you got it back together right the first time too, Earl.

It would be great if we could get one of our aerodynamic engineer friends to run our engine in a makeshift wind tunnel with smoke so that we could see the wind pattern over the engine. I'll bet that you would see one heck of a vortex wrapped around the engine. There may even be negative pressure pockets that could conceivably pull exhaust effluent forward of its exit point on the muffler.


Ed Cregger