Saito FG-60R3
07-29-2019, 10:29 AM
#2376
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Valves sticking is usually a result of either a bent valve, worn valve guides or EXCESSIVE CARBON BUILDUP. The fact that its on the exhaust valve of the cylinder that seems to get the least lubrication, lends some value to your friends suggestion....if you have a look in the exhaust port and see this...
then its quite likely your valve looks like this.....
so a sticky valve is not out of the question.
This is another reason I am trying the negative pressure crankcase mod....the mixture is less rich in oil, more burns off in combustion and doesn't cling to the VERY hot exhaust valve on its way out. I suppose if your engine is running too rich, with any oil mix concentration, this could occur as well... excessive idling, cold starts, low compression and poor combustion, all contribute to excessive carbon build up. Glow engines dont gunk up as much for a number of reasons, one of them is that they dont get as hot so the 'flashpoint' of the oils and castor dont burn onto the valves....( I think, I am not an expert on the topic...or any topic for that matter lol!)
Make sure you are lubing that No1 cylinder valve train...oil her up good!
then its quite likely your valve looks like this.....
so a sticky valve is not out of the question.
This is another reason I am trying the negative pressure crankcase mod....the mixture is less rich in oil, more burns off in combustion and doesn't cling to the VERY hot exhaust valve on its way out. I suppose if your engine is running too rich, with any oil mix concentration, this could occur as well... excessive idling, cold starts, low compression and poor combustion, all contribute to excessive carbon build up. Glow engines dont gunk up as much for a number of reasons, one of them is that they dont get as hot so the 'flashpoint' of the oils and castor dont burn onto the valves....( I think, I am not an expert on the topic...or any topic for that matter lol!)
Make sure you are lubing that No1 cylinder valve train...oil her up good!
07-29-2019, 01:19 PM
#2377
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I am in the process of selecting an exhaust ring for my TF Giant P-47. I believe I read the Keleo must be removed before spark plug wires can be pulled off, which I do not like. I have not heard anything about the Saito ring muffler. It looks small, is positioned close to the intake tubes, and doesn't seem to sound as good in the video. The Meier ring looks very nice, very large, and is probably the least convenient to purchase do to location.
Does anyone regret their purchase or have additional feedback?
Does anyone regret their purchase or have additional feedback?
07-29-2019, 03:14 PM
#2380
My Feedback: (6)
My Caps are at 90 degrees to the thrust line as in sideways this isn't so much a Kelo ring requirement but other considerations.
I safety wire my caps on by drilling a small hole in the exhaust fins and around the spark lead.
I would consider using the Saito provided exhaust tubes.
Sparky
I safety wire my caps on by drilling a small hole in the exhaust fins and around the spark lead.
I would consider using the Saito provided exhaust tubes.
Sparky
07-29-2019, 05:02 PM
#2381
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Thanks all. Its good to know the Keleo does not need to be removed. Maybe I made an assumption based on some pics and a few comments I read.
I also just assumed I would want the exhaust ring, based solely on exhaust tone and easy of packaging inside cowl. Something I can consider.
I also just assumed I would want the exhaust ring, based solely on exhaust tone and easy of packaging inside cowl. Something I can consider.
07-29-2019, 07:34 PM
#2382
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The Keleo one does allow acces to the plugs, but it is a very tight fit. I still think it puts unnecessary stress on the cylinders, but this is just an opinion I built up.
the Morris one DOES hinder the removal and replacement of the plug caps. But it’s the best sounding one. He is making a new ring that connects by ‘olive’ connectors, this will be my preference when they are available.
the Meier one seems to be the best one available at the moment, and also sounds pretty good but I don’t have one so my comments on that are not based on experienc but it connects easily without using a hammer, the diameter of the pipes and ring itself are good.
the Saito one has a good connection method but the pipe diameters are small, it interferes with plug and cap replacement and doesn’t have the deep growl the others have. It’s is well made and nicely put together.
the stock pipes are easiest to use, do their job well, allow you to see whether individual cylinders are richer than others, or whether they are firing properly. They don’t sound as good but are the best at dissipating heat and removing exhaust gasses.
the Morris one DOES hinder the removal and replacement of the plug caps. But it’s the best sounding one. He is making a new ring that connects by ‘olive’ connectors, this will be my preference when they are available.
the Meier one seems to be the best one available at the moment, and also sounds pretty good but I don’t have one so my comments on that are not based on experienc but it connects easily without using a hammer, the diameter of the pipes and ring itself are good.
the Saito one has a good connection method but the pipe diameters are small, it interferes with plug and cap replacement and doesn’t have the deep growl the others have. It’s is well made and nicely put together.
the stock pipes are easiest to use, do their job well, allow you to see whether individual cylinders are richer than others, or whether they are firing properly. They don’t sound as good but are the best at dissipating heat and removing exhaust gasses.
07-30-2019, 12:29 PM
#2383
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Hi gents. Sorry for a bit of an off-topic but I'd like to know your opinion about something. I'm not very experienced with four-stroke engines, I've got a FG33r3 and went through this whole thread so I am aware of your discussions. I have removed a Keleo Exhaust from this engine (flew with it three times, 5 mins each flight) and currently I'm reattaching original Saito tubings. I've put up with the fact that the engine will be written off sooner or later and I would like to ask you if you know anythong about the methanol version of FA-200R3. Whether it has similar problems or whether it has been a trouble-free engine. Is there a possibility of a similar problem with keleo exhaust? I love the sound of a three cilinder engine and therefor I'm considering buying a FA-200r3 or FG-30B engine instead of the fG33r3.. What do you guys think? Thanks in advance for your opinions.
Best regards Adam from Slovakia
Best regards Adam from Slovakia
07-31-2019, 01:40 AM
#2384
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Not sure I understand your question, but my first response would be to ask why you are going to write the engine off? ...or are you thinking ahead in case the FG33R3 fails?
if I were you, i would spend the money on the MorrisMiniMotors or CH-ignitions prop hub and get the timing done right.
In some discussions with Morris, he reckons that the FG33 is the best running engine of all the Saito radials.
converting one of the glow engines is feasible, just get this one running nicely and you’re good to go.
maybe spend any spare money you have on the intake mod as well....seems the FG33’s are the most reliable of the current Saito radial gassers, so I would be tempted to keep it!
if I were you, i would spend the money on the MorrisMiniMotors or CH-ignitions prop hub and get the timing done right.
In some discussions with Morris, he reckons that the FG33 is the best running engine of all the Saito radials.
converting one of the glow engines is feasible, just get this one running nicely and you’re good to go.
maybe spend any spare money you have on the intake mod as well....seems the FG33’s are the most reliable of the current Saito radial gassers, so I would be tempted to keep it!
08-01-2019, 10:34 AM
#2385
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since the past few post are about the Keleo ring, I got a question. I'm waiting fro my motor to be returned from Ray English, he did the timing change fro me and he called me questioning me as to why I had the tap plugged off. I told him I didn't use it and he said that I should because of the carb design. I said I didn't want that black stuff in my tank and he said just make or use a crap trap. do any of you use this to pressurize your tank.? my carb and fuel to carb line are dead inline, but he said If I were to go inverted that I could have a lean run, so I should use the pressure tap. looking forward to getting the engine back next week. Can anyone recommend an plane that has no cowl.
Thanks
Tom
Thanks
Tom
08-01-2019, 12:15 PM
#2386
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I dont know about that, I mean....what about if you're using the stock pipes? there is no 'tap' there to use. Although, saying that, who knows WHAT Saito were thinking about a few things. I believe that when Keleo built the rings originally, that tap was for smoke....early on in this thread, there was talk of the 'danger' of using pressure in a gas system, and although I dont believe there are any inherent dangers of the thing exploding, there is a 'waste spark' on the exhaust stroke, but the chances of unburnt gas vapor, or vapor in the tank igniting, are going to be negligible...I would think.
I don't know of anyone here, or elsewhere, that is using that to pressurise the tank.
For what its worth, I have found that carb to be VERY GOOD at drawing fuel, and in one of the applications I used it in, the tank was a fair distance from the carb, and it pulled fuel just fine. Before I pressurised the tank, I would opt for one of Morris's little pumps that he sells. I cannot justify spending money on one right now, but I would consider it if ever I thought there was a chance of going to lean, or inconsistent fuel delivery...
Planes without a cowl would probably be WW1 type planes I would imagine, unless you want to put it on an Ugly Stik or similar.......either way, chances of you flying inverted for any length of time are?....
Oh, and yes, I agree, there is a lot of smoke and oil residue with 20:1 mix, so the likelihood of getting that crap in your fuel tank, is pretty high...
I don't know of anyone here, or elsewhere, that is using that to pressurise the tank.
For what its worth, I have found that carb to be VERY GOOD at drawing fuel, and in one of the applications I used it in, the tank was a fair distance from the carb, and it pulled fuel just fine. Before I pressurised the tank, I would opt for one of Morris's little pumps that he sells. I cannot justify spending money on one right now, but I would consider it if ever I thought there was a chance of going to lean, or inconsistent fuel delivery...
Planes without a cowl would probably be WW1 type planes I would imagine, unless you want to put it on an Ugly Stik or similar.......either way, chances of you flying inverted for any length of time are?....
Oh, and yes, I agree, there is a lot of smoke and oil residue with 20:1 mix, so the likelihood of getting that crap in your fuel tank, is pretty high...
08-01-2019, 05:12 PM
#2387
My Feedback: (6)
I am using the Kelo Muffler pressure tap as the vent from my fuel tank. I don't think there is much pressure going to the tank the fuel line looks reasonably clear. It serves as the overflow for the tank so when fuel runs from the muffler I have a full tank,.
I'm running a two line fuel delivery system with a T in the fuel feed line that is used for refueling. It is capped off for running.
I have no concerns about getting feedback into the fuel tank.
My Crank case vent feeds into the exhaust.
Sparky
I'm running a two line fuel delivery system with a T in the fuel feed line that is used for refueling. It is capped off for running.
I have no concerns about getting feedback into the fuel tank.
My Crank case vent feeds into the exhaust.
Sparky
08-01-2019, 10:59 PM
#2388
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Well there’s one! Do you not think it is creating much of pump pressure? If anything, it would be nice to be able to block the exhaust and help get fuel through to the carb after it hasn’t run for a while...
i might have to experiment.
i might have to experiment.
08-02-2019, 04:52 AM
#2389
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I am using the Kelo Muffler pressure tap as the vent from my fuel tank. I don't think there is much pressure going to the tank the fuel line looks reasonably clear. It serves as the overflow for the tank so when fuel runs from the muffler I have a full tank,.
I'm running a two line fuel delivery system with a T in the fuel feed line that is used for refueling. It is capped off for running.
I have no concerns about getting feedback into the fuel tank.
My Crank case vent feeds into the exhaust.
Sparky
I'm running a two line fuel delivery system with a T in the fuel feed line that is used for refueling. It is capped off for running.
I have no concerns about getting feedback into the fuel tank.
My Crank case vent feeds into the exhaust.
Sparky
08-02-2019, 11:44 AM
#2391
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Yeah, the manual states on page 3, Fig. 8 that you are supposed to place the breather pipe in the 'blast' of the exhaust, it creates negative pressure at the end of the pipe, and basically 'extracts' the excess oil from the crankcase. They don't say anywhere to apply pressure to the tank... Anyone noticed in the latest manual that there are a few points 'blanked out in red on the last page of the manual, point 3....I will have to dig out my manual and see if I can see what they've removed..lol.
The carb draws fuel really well, and is a clever design. I dont know why they wouldn't put a choke on it, but I suspect it might be one of two things...a) fear of people flooding the engine and causing a hydrolock. This is a possibility, if you've ever held your finger over the carb opening, and turned it over a few times, it REALLY sucks fuel through and you have a wet finger very quickly. b) doing what I have just mentioned, may damage the diaphragms.
I have opened one up and it is a weird pump system...the rectangular 'box' part, with Saito written on the top, has a top cover, a middle part and then the carb body. Between the parts there are two plastic filaments with a spring and two little 'plungers', one in each compartment. They are not soft diaphragms like in a walbro, but more like transparent film. The top cover has hole in it, and drilled holes in the carb, I dont think its using 'pulses' like a walbro, it seems the the negative pressure from inside the carb, forces the little plungers against the filaments and then the spring overcomes that, and the hole in the top allows them to return to position, thereby creating a vacuum which sucks the fuel through. I am not a specialist in this department but it sure seems like it is a positive pumping action and does the job pretty well. I am adverse to replacing it with the Walbro carb mod that does rely on 'pulses' although the FG84 and 90 look to have the components of a walbro (diaphragms are similar) and it seems to work ok in those applications. I would like to open up one of those one day and investigate, and I have one on my FG40, but will leave that until the day I need to open it to rebuild diaphragms.
Its just my opinion, but I think the carb does well enough without pressurisation, but I also dont think you are unlikely to do any harm by doing it. If you are going to do it, a craptrap might help, and using a good felt clunk would probably prevent too much residue getting in the. I will give it a go on Frankensaito, but this weekend we are going to shift the timing from 30Deg BTDC to 34Deg, and see if it has any impact on running. Will report back later...
The carb draws fuel really well, and is a clever design. I dont know why they wouldn't put a choke on it, but I suspect it might be one of two things...a) fear of people flooding the engine and causing a hydrolock. This is a possibility, if you've ever held your finger over the carb opening, and turned it over a few times, it REALLY sucks fuel through and you have a wet finger very quickly. b) doing what I have just mentioned, may damage the diaphragms.
I have opened one up and it is a weird pump system...the rectangular 'box' part, with Saito written on the top, has a top cover, a middle part and then the carb body. Between the parts there are two plastic filaments with a spring and two little 'plungers', one in each compartment. They are not soft diaphragms like in a walbro, but more like transparent film. The top cover has hole in it, and drilled holes in the carb, I dont think its using 'pulses' like a walbro, it seems the the negative pressure from inside the carb, forces the little plungers against the filaments and then the spring overcomes that, and the hole in the top allows them to return to position, thereby creating a vacuum which sucks the fuel through. I am not a specialist in this department but it sure seems like it is a positive pumping action and does the job pretty well. I am adverse to replacing it with the Walbro carb mod that does rely on 'pulses' although the FG84 and 90 look to have the components of a walbro (diaphragms are similar) and it seems to work ok in those applications. I would like to open up one of those one day and investigate, and I have one on my FG40, but will leave that until the day I need to open it to rebuild diaphragms.
Its just my opinion, but I think the carb does well enough without pressurisation, but I also dont think you are unlikely to do any harm by doing it. If you are going to do it, a craptrap might help, and using a good felt clunk would probably prevent too much residue getting in the. I will give it a go on Frankensaito, but this weekend we are going to shift the timing from 30Deg BTDC to 34Deg, and see if it has any impact on running. Will report back later...
08-02-2019, 06:25 PM
#2392
My Feedback: (6)
I doubt you will see any difference in the flight characteristics by changing the timing 4 degrees as you propose on a download of the engine you might see the difference.
Two flights today NO issues. On the taxi in I pull the idle down to 1000 RPM just for the sound.
I filter my fuel before t goes in the plane and no filters are in the plane.
flying in a contest tomorrow.
Sparky
Two flights today NO issues. On the taxi in I pull the idle down to 1000 RPM just for the sound.
I filter my fuel before t goes in the plane and no filters are in the plane.
flying in a contest tomorrow.
Sparky
08-02-2019, 08:11 PM
#2393
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Sparky, not really expecting any ‘visible’ gains/losses by changing the timing, but was hoping to see a change in temperature, even if it’s a small change, hopefully a few degrees lower.
glad to hear yours is still running well, and the idle at 1000rpm is cool for sure. Did you manage to try a higher pitch prop?
what event are you taking part in, and what discipline (scale, best sounding, best looking?) make sure to get some pics to share with us!
each to their own, but I prefer felt clunks in my fuel systems, they provide filtering and when transitioning to inverted or maneuvering, they tend not to suck up air bubbles...
good luck at the show!
glad to hear yours is still running well, and the idle at 1000rpm is cool for sure. Did you manage to try a higher pitch prop?
what event are you taking part in, and what discipline (scale, best sounding, best looking?) make sure to get some pics to share with us!
each to their own, but I prefer felt clunks in my fuel systems, they provide filtering and when transitioning to inverted or maneuvering, they tend not to suck up air bubbles...
good luck at the show!
08-02-2019, 09:14 PM
#2394
I had an odd issue come up last week. The Keleo pressure tap was used as the vent like has been talked about before but the tygon tubing melted after 3 flights causing a blockage. I noticed the engine running hot at the end of the 3rd flight so I landed. Come to find out the engine was leaning out trying to suck gas out of the tank.
Replumbed the tank and plugged the fitting on the exhaust so it’s running just like the FG84 or 90.
Im using the black tubing for gas from the crank case to the exhaust for oil overflow.
I did see a lot of carbon/oil build up running back up the vent tube towards the tank. Not a fan of this even with a crap rap. Plus I have seen this engine have the characteristic stumble in flight as I roll the airplane. Still not sure why these engines do this but it’s been a characteristic of the 84, 90 and the 60 in my experience. I guess the positive tank pressure is not the answer.
Replumbed the tank and plugged the fitting on the exhaust so it’s running just like the FG84 or 90.
Im using the black tubing for gas from the crank case to the exhaust for oil overflow.
I did see a lot of carbon/oil build up running back up the vent tube towards the tank. Not a fan of this even with a crap rap. Plus I have seen this engine have the characteristic stumble in flight as I roll the airplane. Still not sure why these engines do this but it’s been a characteristic of the 84, 90 and the 60 in my experience. I guess the positive tank pressure is not the answer.
08-02-2019, 09:59 PM
#2395
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Chris, ok, that’s an undesirable state to not be able to draw fuel! I suppose using high temp like neoprene tube might reduce the melting risk, but I’m still opposed to having exhaust fumes in the tank. Gassers run hotter than glow so exhaust temps are less likely to melt the tygon.
ive not had the stumble you speak of, but my mate’s FG90 has, and my FG40 definitely has. Even the instructions suggest holding the plane in a certain orientation for the first flight of the day but really, a 90cc plane has to be held up like a .40 glow to get bubbles out?!!? Ridiculous.
the FG60 carb doesn’t do it on either of my engines..
ive not had the stumble you speak of, but my mate’s FG90 has, and my FG40 definitely has. Even the instructions suggest holding the plane in a certain orientation for the first flight of the day but really, a 90cc plane has to be held up like a .40 glow to get bubbles out?!!? Ridiculous.
the FG60 carb doesn’t do it on either of my engines..
08-03-2019, 01:53 AM
#2396
Hey everyone i'm joining the fg-60 family, I will be installing it in a seagull p-47, I've ordered the MMM timing ring, is there anything else that is a must have to keep this motor humming? Also could someone steer me to a p-47 style spinner ,I plan on running either a 22x10 or 22x12 xoar ww2 prop.
Thanks Jim
Thanks Jim
08-03-2019, 04:17 AM
#2397
My Feedback: (2)
Hey everyone i'm joining the fg-60 family, I will be installing it in a seagull p-47, I've ordered the MMM timing ring, is there anything else that is a must have to keep this motor humming? Also could someone steer me to a p-47 style spinner ,I plan on running either a 22x10 or 22x12 xoar ww2 prop.
Thanks Jim
Thanks Jim
On B/O at the moment though.
08-03-2019, 06:25 AM
#2399
Air Purging of the Walbro Carburetor; FG30B, 36B, 40, 57T, 84R3, 90R3
The instructions state " if the airplane is too large and heavy to handle by yourself , Do Not try purging on the ground. Then at first flight, gain height high enough and incline the airplane to roll slowly and carefully toward the Metering room which is opposite of the throttle lever.
I do this procedure on the first flight of the day at approximately 300 feet, I do three slow rolls for the air purge. It works well, no coughing after the rolls are completed. The FG60 does not have a Walbro carburetor, thus it does not have the symptoms of coughing like the engines listed above.
The instructions state " if the airplane is too large and heavy to handle by yourself , Do Not try purging on the ground. Then at first flight, gain height high enough and incline the airplane to roll slowly and carefully toward the Metering room which is opposite of the throttle lever.
I do this procedure on the first flight of the day at approximately 300 feet, I do three slow rolls for the air purge. It works well, no coughing after the rolls are completed. The FG60 does not have a Walbro carburetor, thus it does not have the symptoms of coughing like the engines listed above.
08-03-2019, 02:16 PM
#2400
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Yeah, the manual states on page 3, Fig. 8 that you are supposed to place the breather pipe in the 'blast' of the exhaust, it creates negative pressure at the end of the pipe, and basically 'extracts' the excess oil from the crankcase. They don't say anywhere to apply pressure to the tank... Anyone noticed in the latest manual that there are a few points 'blanked out in red on the last page of the manual, point 3....I will have to dig out my manual and see if I can see what they've removed..lol.
The carb draws fuel really well, and is a clever design. I dont know why they wouldn't put a choke on it, but I suspect it might be one of two things...a) fear of people flooding the engine and causing a hydrolock. This is a possibility, if you've ever held your finger over the carb opening, and turned it over a few times, it REALLY sucks fuel through and you have a wet finger very quickly. b) doing what I have just mentioned, may damage the diaphragms.
I have opened one up and it is a weird pump system...the rectangular 'box' part, with Saito written on the top, has a top cover, a middle part and then the carb body. Between the parts there are two plastic filaments with a spring and two little 'plungers', one in each compartment. They are not soft diaphragms like in a walbro, but more like transparent film. The top cover has hole in it, and drilled holes in the carb, I dont think its using 'pulses' like a walbro, it seems the the negative pressure from inside the carb, forces the little plungers against the filaments and then the spring overcomes that, and the hole in the top allows them to return to position, thereby creating a vacuum which sucks the fuel through. I am not a specialist in this department but it sure seems like it is a positive pumping action and does the job pretty well. I am adverse to replacing it with the Walbro carb mod that does rely on 'pulses' although the FG84 and 90 look to have the components of a walbro (diaphragms are similar) and it seems to work ok in those applications. I would like to open up one of those one day and investigate, and I have one on my FG40, but will leave that until the day I need to open it to rebuild diaphragms.
Its just my opinion, but I think the carb does well enough without pressurisation, but I also dont think you are unlikely to do any harm by doing it. If you are going to do it, a craptrap might help, and using a good felt clunk would probably prevent too much residue getting in the. I will give it a go on Frankensaito, but this weekend we are going to shift the timing from 30Deg BTDC to 34Deg, and see if it has any impact on running. Will report back later...
The carb draws fuel really well, and is a clever design. I dont know why they wouldn't put a choke on it, but I suspect it might be one of two things...a) fear of people flooding the engine and causing a hydrolock. This is a possibility, if you've ever held your finger over the carb opening, and turned it over a few times, it REALLY sucks fuel through and you have a wet finger very quickly. b) doing what I have just mentioned, may damage the diaphragms.
I have opened one up and it is a weird pump system...the rectangular 'box' part, with Saito written on the top, has a top cover, a middle part and then the carb body. Between the parts there are two plastic filaments with a spring and two little 'plungers', one in each compartment. They are not soft diaphragms like in a walbro, but more like transparent film. The top cover has hole in it, and drilled holes in the carb, I dont think its using 'pulses' like a walbro, it seems the the negative pressure from inside the carb, forces the little plungers against the filaments and then the spring overcomes that, and the hole in the top allows them to return to position, thereby creating a vacuum which sucks the fuel through. I am not a specialist in this department but it sure seems like it is a positive pumping action and does the job pretty well. I am adverse to replacing it with the Walbro carb mod that does rely on 'pulses' although the FG84 and 90 look to have the components of a walbro (diaphragms are similar) and it seems to work ok in those applications. I would like to open up one of those one day and investigate, and I have one on my FG40, but will leave that until the day I need to open it to rebuild diaphragms.
Its just my opinion, but I think the carb does well enough without pressurisation, but I also dont think you are unlikely to do any harm by doing it. If you are going to do it, a craptrap might help, and using a good felt clunk would probably prevent too much residue getting in the. I will give it a go on Frankensaito, but this weekend we are going to shift the timing from 30Deg BTDC to 34Deg, and see if it has any impact on running. Will report back later...
so I understand, the vent line from the tank should hook up to the exhaust? I have a Keleo on mine. I just run mine out the bottom of the plane along with the crankcase vent on the Saito. Is this incorrect? Motor runs good and has no issues at all when rolling the plane inverted. Got to love the Roto-Flow tank!
Brad