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Saito FG-60R3

Old 11-17-2019, 10:55 PM
  #2576  
Enjoyav8tion
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Well Iíve got a FG 90 on the way. Even if I have to relocate the firewall I think itíll be better than all the mods.
Old 11-18-2019, 07:11 AM
  #2577  
757jonp
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Enjoy.... That's gonna be a "honker" on there LOL. I just stuffed a FG-90 on a Ziroli Texan/Harvard and had a good time doing it. Worked out well in the end weight wise, but had to a 2 inch longer cowl because I didn't want to recess the engine into the fuse. See you on the FG-90 thread?
Old 11-18-2019, 02:09 PM
  #2578  
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Default Fg 90

Yea I know itís going to be an uphill battle. Itís fine. I can still split the cowl, put part of the carb in the plane or maybe not use the offsets. Yep switching to the 90 chat. Thanks guys for your help and advice
Old 11-20-2019, 01:09 AM
  #2579  
cathurga
 
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Hey all, I managed to get some time to pull the engine off the plane, and do some inspection and teardown. Here are my observations, and I'm still in the dark as to what the ACTUAL cause of the failure was, but its my suspicion that there are a number of contributors.
Quick recap:
This engine was bought from a guy on these forums, and he had experienced a cylinder failure prior to me getting my hands on it, the cylinder that failed, was replaced under warranty, but this was before the new cylinder and piston design, so an original combo was used. I flew the engine many times in this format, using 20:1 redline, original timing setup and it never really flew well. It was on a 50cc Yak 3D plane and would barely tug it around....it was just disappointing. Tried a number of props 22x10 was the best of the lot, but tried 22x8, 21x12 but the thing never really excelled they way I was hoping. It went to the bench and was just being tested for all sorts....eventually got the timing sorted (I just rotated the hub on the crankshaft to get the timing to 28Deg). Eventually it got the MMM ring, and it just seemed to be running nicer, crisp throttle, good idle and seemed happier. We decided to run it on the SeaFury with the 4-bladed prop, as a test bed and after a while of good flying, it unexpectedly threw No3. I cant recall if we did the crankcase mod before or after that but the cylinder was replaced with the new design piston and cylinder. We have done maybe 30 flights in this config, until the other day, when it threw No2, also an original piston/cylinder combo.

So here we are now....upon removal there was NO leakage past the exhaust connectors (thanks Loctite flange sealer). There was NO leakage past the rocker gaskets (we put new ones on, but the crankcase mod is not allowing spooge out, so thats good). No 2 rocker cover bolts were all uniformly tight, nothing loose. There was PLENTY of lube on the valvetrain...nice and soaked in slippery stuff...The crankcase also had oil sloshing around in the bottom, but not nearly as much as I was expecting, I was fully expecting to have to POUR oil out since the crankcase mode, but it was maybe a few ml more than the last time I opened it up before the mod. Since we were running this on 30:1, there is less oil in both the air/fuel mix, as well as whats blowing by the rings...the excess might be getting atomised and passing through the combustion process...bottom line, I was happy to see that...Quite surprisingly there was NO gap on the inlet valve...it was not open, but the tappet gap was closed that there was no detectable gap. I thought it might have caused some burning/bypass on the inlet valve seats, but once we removed that, its apparent there was NO burning, and the seat and valve were clear and clean. The exhaust valve had a normal gap and was functioning well. There was some carbon buildup, but that has been there a long time but has not gotten any worse, in fact, when the last clylnider let go, there was a LOT of carbon on that one, as well as in the combustion chamber and on the piston crown. THis one had acceptable amonts of buildup in my opinion and most likely because we have run it on Stihl for the last 30 or so flights...we also put some engine cleaner treatment in a few tanks....could it be possible this has helped clean, or keep clean??
There is some weird marking on the piston and cylinder lining, but I dont know if this is from normal running or whether its happened after the cylinder went....the engine was still running, and we landed it still idling and running on 2, so with the cyl slighty crooked, it may have put the wier marks on it. They are not gouges at all, just seem like wear marks...
If you look at the pics, you can see that the cracks are EXACTLY where the new cylinders have been beefed up by Saito...and MOST of the other failures I have seen have been in a similar place (barring the incidents where engines have dismantled in flight and broken a lot more). My immediate reaction is that the cylinder material is not enough to cope with standard compression, and the timing has exposed that weakness. Even on my engine, with the amount of time it has been flying, its just been one 'bridge too far' on the metallurgy. I think that everyone with an older engine, is likely to have a failure at some point, and that failure will come sooner if you dont change the timing. I also suspect that running a 2-bladed prop is going to load the engine less, and will increase the time before a failure. If you manage to get a lot of flight time before that day comes, you are one of the lucky ones, and I know that some people may get a lifetime of use out of their engines, without any problems. If you are one of those people...go buy lottery tickets!

We are going to repair Frankensaito, but this time it will have ALL new version Pistons, Rings and Cylinders. We will put new valves in as well. Will continue to run it on the MMM timing at 28Deg, the crankcase mod from MMM and Stihl 30:1 mixed with pump gas...prepping to order parts, and will return once fitted up.

Pics here.



In situ cracks


Other side


Crown wiped clean with cloth



Crown before clean


Crankcase oil level


Combustion Chamber


Piston scoring
Old 01-13-2020, 04:10 AM
  #2580  
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I’m curious what people suggest for break in fuel mix, in my situation:

I have an earlier FG60R3 without the modified cylinders, that’s still unrun but a few years old so presumably out of warranty. I’ve ordered the Morris Mini Motors intake kit and new prop driver/magnet ring, which I’ll be fitting before turning it over. Also Keleo exhaust.

So, given the intake mod and therefore ability to run on much lower oil mix (Morris uses about 30:1 from memory) I’m wondering what a safe run-in mix would be. Also whether the 4000 rpm sloppy run in is still ideal?

Happy to hear if anyone has had one from new with the MMM mods, and what their experience was.

Cheers,

Cam.
Old 01-13-2020, 06:56 AM
  #2581  
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I don't have the 60R3 but have the 90R3 and bought the intake from MMM.
I told him that my engine was VERY low run time and should I continue to break in on 18-20:1?
He said go straight to 32:1. I'll do that but richen it up a bit initially.

Cheers,
Dave.
Old 01-13-2020, 09:32 PM
  #2582  
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Camdy, I assume your engine has not run yet? If so, I would make sure to get some lube into it before running it, I mean manually lube it. Since you are taking the back plate off to change to the intake mod, just drop some oil into the moving parts, no need to go crazy, but just lightly to have some oil in there on first run. Put your initial mix at 30:1 and run it rich as per the manual, sloppy. It helps to have the original exhausts on it so you can see which cylinders are firing and which not. I inverted mine for half of the break in so that 2 and 3 also get some heat cycling. The thread is full of info on the break in process. After 2 tanks like that, I would set it up for flight (not on the cusp of going lean, just so you are getting good revs and a stable idle). Before doing anything, get the timing set up at 28 Degrees BTDC!
As in my posts, even with the intake and timing mods, mine still bust a cylinder, but that could be a number of factors at play:
The cylinder material in the place it breaks, is weak, thats why they have changed it
Compression is high, which is why they have changed the piston
The above two conditions combine to cause potential failure.

I have also abused the engine of mine, it runs in really high ambient temps, it had a 4-bladed prop on it and was run in its original state for a long time before the mods, so this could have caused problems which appeared later.

I suggest to make sure it is nicely cooled/baffled, run it on a 22x10 or 21x12 (depending on air frame) two-blade prop, and use Stihl HP oil and make sure it doesnt run too lean. This isnt a high performance engine, so treat it ias such. Trying to get the last rev out of it will likely cause some problems. After that, you hope you have one that lasts.

If you bought it new, before you run it, take it back to the place you bought it and TELL them that there are changes to new components, you have proof here, and tell them to send it back and get the new version. You will STILL need to change the timing, and the intake mod is always going to be a good option from a longevity perspective.

Good luck
Old 01-13-2020, 10:38 PM
  #2583  
elmshoot
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If you bought it new, before you run it, take it back to the place you bought it and TELL them that there are changes to new components, you have proof here, and tell them to send it back and get the new version. You will STILL need to change the timing, and the intake mod is always going to be a good option from a longevity perspective.

Good luck[/QUOTE]
Do you know what version you have? Look through here to figure it out.
I doubt they will do anything at the hobby shop other than look at you with a blank stare... Horizon has an OUTSTANDING reputation for doing the right thing but I doubt that Horizon will honer any upgrades request. You could call Horizon directly and see if they are willing to do the upgrades.
Its easy to follow there breakin protocol. 20:1 oil . I use the red line oil available here in the US. For fuel I run methanol free gas and as low an octain as i can get.
Sparky


Old 01-14-2020, 03:39 PM
  #2584  
camdyson
 
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Originally Posted by mogman View Post
I don't have the 60R3 but have the 90R3 and bought the intake from MMM.
I told him that my engine was VERY low run time and should I continue to break in on 18-20:1?
He said go straight to 32:1. I'll do that but richen it up a bit initially.

Cheers,
Dave.
Wow - 32:1 on break in? Will definitely be lubing thoroughly and watching closely if I do that!

Whilst the older pistons/cylinders are a concern, a couple of my flying buddies have run this engine stock and not had issues, so with the modifications I feel I'll be ok. I fly slow and scale, so my engines have a pretty easy life.

Cam
Old 01-15-2020, 05:15 AM
  #2585  
cathurga
 
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30:1 is fine, as the oily fuel mix will be going through the crankcase, unlike normally where oil needs to make it past the rings first. With the mod, you have the best of both worlds.
Run it on 20:1 for a tank or two if you want but imho, that rich, with little oil burning off, leads to carbon.
i wonít open the can of worms that is the oil debate, but redline is great for high revving two-strokes, like go-karts. My personal feeling is that Stihl HP, or even HP ultra if you can get it, is preferable.
lots of people have been flying the engine without problems, ....you wonít find any of them on this thread. We are all the poor bums that lucked out...and Saito have made revisions, denied doing so...but we know...

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