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Saito FG-60R3

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Old 05-23-2019, 08:36 AM
  #2251  
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BH177-Fairchild 24W | Blackhorsemodel
Soft dirt is good....

Fairchild 24
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Old 05-24-2019, 04:03 AM
  #2252  
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Oh no! That's harsh, although it looks like you got a little lucky! Before you make assumptions, you may also want to check if there is any run-out on the crankshaft as well, I would think a shock impact might bend the shaft, depending on the angle of impact. Also, the pushrod tube that is bent, might also have a bent pushrod as well....

Elmshoot is 100% correct on soft dirt being good. One of the guys at our field had one installed on a Hangar 9 Stik, and the empennage detached itself in flight, and the thing went from horizontal flight, vertically down and into the tarmac runway, at full bore.....not much left of that engine!
I hear you about the sealed being 'airtight', and am armed with some electrical cleaner in a can, so I can squirt it at certain points (i.e rubbers, tappet covers, pushrod seals etc etc) and see if I can find a leak. I have lots of the tappet cover seals, the inlet seals and rings, but I dont have any of the pushrod tube seals, so hopefully during running tomorrow, I can find a leak somewhere. Suspect it might be the tappet cover seals.

As far as my 'tinkering' goes....yeah....someone just try stop me LOL!
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Old 05-24-2019, 04:13 AM
  #2253  
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Timbers,
I would consider the prop hub from MMM as the FIRST mod that I would do. The timing on the engine is too aggressive. The only reason I am trialing the intake mod is because I am in the extreme heat of the desert, so my running temps are a concern as well as the fact that 20:1 ratio is causing me carbon build up. The intake mod allows me to decrease the oil content by 10:1.
If I was in your shoes, with an engine that runs well, I would leave it as is, with the exception of the prop hub adaptor. Even if you find you want to move the timing back to where it is now, you can do it without changing the prob hub back, you can just do it on the MMM one anyway. I suspect though, that once you get a nice stable idle, nice transition and smoother running, you will want to leave the timing at around 30Deg BTDC, or if you are wanting more power, then 34 Deg BTDC. As it is now, you are at a minimum, at least 40Deg BTDC.

Regarding the pushrods jumping out.....these engines dont like high revs....at least from my findings....this is a likely cause of them jumping out...because a valve 'bounces' and thats the result. I dont know what you are flying it in, but if the airframe allows is, go down in diameter on the prop, and up the pitch. Or if it is revving high now, maybe up the pitch an inch. Use the usual caution when testing.
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Old 05-24-2019, 09:21 PM
  #2254  
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Originally Posted by cathurga View Post
Oh no! That's harsh, although it looks like you got a little lucky! Before you make assumptions, you may also want to check if there is any run-out on the crankshaft as well, I would think a shock impact might bend the shaft, depending on the angle of impact. Also, the pushrod tube that is bent, might also have a bent pushrod as well....

Elmshoot is 100% correct on soft dirt being good. One of the guys at our field had one installed on a Hangar 9 Stik, and the empennage detached itself in flight, and the thing went from horizontal flight, vertically down and into the tarmac runway, at full bore.....not much left of that engine!
I hear you about the sealed being 'airtight', and am armed with some electrical cleaner in a can, so I can squirt it at certain points (i.e rubbers, tappet covers, pushrod seals etc etc) and see if I can find a leak. I have lots of the tappet cover seals, the inlet seals and rings, but I dont have any of the pushrod tube seals, so hopefully during running tomorrow, I can find a leak somewhere. Suspect it might be the tappet cover seals.

As far as my 'tinkering' goes....yeah....someone just try stop me LOL!

Don't worry, everything has been checked, and since the reassembly the engine has already worked 2 hours without any problem.
FYI, on the picture, the condition of the 3 pistons (without cleaning after disassembly) after nearly 40 hours of operation.
I also feel that since I reassembled the Saito carburetor, the engine is more sensitive to the fuel level in the tank, and I feel like it works better when the level is at above the carburetor. Have other users made the same observation?




JM

Last edited by JieM; 05-24-2019 at 09:43 PM.
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Old 05-25-2019, 01:31 AM
  #2255  
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Thats amazing, and good to know it is back up and running properly. The pistons look very clean, would be interesting to see what your valves looked like. You have modified your intake for negative pressure as well, right? Did you get some new intake tubes, those look a little buckled :-) Or did you just make them right again? New pushrods?
I am going to be doing some tinkering this afternoon on my engine, and am hoping that I have everything sorted out that it will run properly. Its just on its stand at the moment, so once its all looking ok, I will put it back on the plane again.

Good to see yours in running properly now. I hope you manage to find a nice plane to put it on. I saw some videos of guys flying it in the Seagull Lysander which looks pretty cool but I have to admit I would get a little bored of the high wing, slow flying planes....warbirds are more fun :-) but typically they are a bit of a handful. If you are looking at a warbird, the VQ Bearcat looks like it was MADE for these engines and it fly's like a big old trainer from what I can see. Didier has the racing version and he clipped the wings, which looks great. He has contributed to the OTHER forum with some updates and video's, looks great and his engine appears to be running like a train!

Thanks for all your contributions to this thread, great experience with this engine.....and good that people are persevering with them.

BTW, feel free to make a batch of cylinder gaskets and shove them in an envelope and send them to Dubai... I dont have the patience or the skills, or the material.....but I would happily recompense in some way... :-)
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Old 05-25-2019, 10:38 AM
  #2256  
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Well, some interesting news from today's tinkering:
The engine did not want to start easily, so had to put it on a starter, which co-erced it into life, but it wasnt running well still. Managed to get it to stabilise at around 3000 rpm, and started spraying contact cleaner at all the points where unregulated air could get in. Rocker covers, inlet tubes to and bottom, crankcase breather and lastly....carb and the phenolic tube...immediately as the spray hit the phenolic tube...it started stalling...Stopped the engine immediately and took it off the stand. The new carb throttle body arrived with a white coloured phenolic tube, and it is quite 'rough', wasnt taking any chances and put a thin layer of HT RTV sealant on both sides, where it goes into the engine, as well as the carb. Shoved it back on. I noted that the original phenolic tubes from the factory engine, had a 'step' in it, as per my diagram I posted previously, this one does NOT have the step so I think that the screw holding the carb on, is actually pushing the tube skew. Before checking that, I wanted to make sure the engine was running properly. It did on the stand, so it went back on the SeaFury....

The following is the result:



Same 4-bladed prop, running 93 octane fuel, 30:1 Stihl HP oil....
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Old 05-26-2019, 03:09 AM
  #2257  
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Just as a point of interest, the LSN is still turned out a LOOONG way....its probably around 5.5-6 turns out! Previously I was on around 4. I replaced the throttle body and in order to do this, I had to remove the 'pump' section from the old one, and put it on the new body. I also replaced the LSN screw, and used a tiny dab of flange sealer on the threads as it is not a tight fit and LSN seems to be prone to turning on its own. That setup with the throttle lever tube, holding the LSN tight with an o-ring is not the sharpest idea I have ever seen.
The distance have to turn, between too rich and too lean on the LSN, is around 1/5 of a turn, I seem to remember more adjustability on this engine previously, but I could well be wrong...
Anyway, enough tinkering for now....going to fly it for as long as possible in this configuration, although Mike hates the sound of the exhaust, so we might slap the Keleo back on it :-)
In other words, more tinkering...

Hers a little vid of yeaterday's landing...

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Old 05-26-2019, 07:52 PM
  #2258  
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Nice!
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Old 05-27-2019, 12:45 AM
  #2259  
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Originally Posted by cathurga View Post
If you are looking at a warbird, the VQ Bearcat looks like it was MADE for these engines and it fly's like a big old trainer from what I can see. Didier has the racing version and he clipped the wings, which looks great. He has contributed to the OTHER forum with some updates and video's, looks great and his engine appears to be running like a train!
Yep. I can confirm that the VQ RareBear is a nice flying model and the FG60R3 fits the model perfectly.
I clipped the wings of the RareBear as VQ didn't do it for several reasons. VQ were really impressed and consider to make the clipped wing version them self and sell them as an option.








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Old 05-27-2019, 12:46 AM
  #2260  
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Here is the video of the clipped wing RareBear

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Old 05-27-2019, 03:17 AM
  #2261  
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Didier, thatís actually quite a lot that you chopped off! I would have thought the thing would roll like a drillbit with that much removed. I suppose you have also removed some aileron as well so may cancel things out a bit.
Are you running stock exhausts?
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Old 05-27-2019, 05:20 AM
  #2262  
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Originally Posted by cathurga View Post
Didier, that’s actually quite a lot that you chopped off! I would have thought the thing would roll like a drillbit with that much removed. I suppose you have also removed some aileron as well so may cancel things out a bit.
Are you running stock exhausts?
The funny thing is I actually had to add 5% dual-rate on ailerons to get the same feeling as the original wing set-up.
Although the wings are clipped, the ailerons were clipped as well around 40%! (check picture 1,2,3)
The exhaust is a Meier. I gives such a deep tone, everybody thinks it is a Moki radial. I guess that's a compliment!
https://www.meier-ringschalldaempfer.com



Last edited by Didier; 05-27-2019 at 05:24 AM.
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Old 05-27-2019, 06:26 AM
  #2263  
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Very cool! I suppose if someone had the knowledge and went to the effort, they could explain the science and aerodynamics as to why the clipping of the wings has made it behave like it does...for us though,...looks great, flies great! Yahoo!!
the Meier rings look like they fit properly... the MMM one sounds great, but is the same design as the keleo, both of which donít fill me with confidence with the way they fit. Morris is redesigning his with Ďoliveí glands which will be similar to the Meier ones and hopefully he will look at the spark plug fittings as well. The Saito ring is nothing special, but fits with the same method as the Meier but getting the plugs on is a right old struggle.
i like the Meier one a lot.
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Old 05-28-2019, 01:24 AM
  #2264  
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The Meier is a great exhaust ring and does not interfere with the spark plug caps.
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Old 06-01-2019, 06:46 AM
  #2265  
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We got a few more flights in on the Sea Fury this weekend, all successful and the engine is running well it seems. We removed the temp sensor because it was causing us too much concern, and the fact that the ambient temps here are high, it casts some doubt as to the accuracy. Its also making us 'baby' the thing too much. Since doing the MMM negative crank pressure mod, it seems that the No1 exhaust valve is getting more lube. After the flights this weekend, I popped off the tappet cover on the ex and saw liquid oil in there! Its the FIRST time I have EVER seen that on this engine, so its a positive thing! I still will drop a little oil in there just to keep things 'slippery'.
Other observations are:
  • The oil ratio at 30:1 is creating a LOT cleaner burning engine, hopefully not because it is too little oil, but hopefully because it is running more efficiently since it is not so reliant on 'blowby' of the rings for lube. The air/oil/fuel mix going through the crank + the 'blowby' is getting enough oil in there.
  • We took the stock exhausts off, and put the Keleo ring back on, in the process, I had a look in the exhaust port and it looks dusty, and NOT all sludgy-carboned up. It looks to be cleaner and like what you would expect an engine exhaust port to look like.
  • The engine is idling very well, stable at 1000-1100rpm. It will idle at around 950 but its not as comfortable there. This leads me to believe that the timing could be advanced just a little, it 30deg right now, but going to push it up to 34deg. The curve of the ignition is maxed at 28Deg @ 4000rpm, but at higher revs, it would probably do better with 34deg and get a little more efficiency. We are getting 5500rpm static on the 4-bladed prop, but dont have a rev telemetry so going to hook one up, and see what it revs out at in flight. I would expect that it should make at least 6500rpm so having a little more advance might help.
On the timing matter, it would be really cool to have the ability to program your own curve into the ignition box. I suppose this is a 'closely guarded' secret and since the engine manufacturers dont make the ignitions, it would create some warranty matters if people messed around with it by themselves. The timing curve of the ignition plus the ability to move the hall sensor, is very likely going to open up a pandora's box of people burning holes in their engines by screwing up the timing. For those that ARE interested though, imagine an 'app' for your phone, connected to a bluetooth module that would allow you to make custom ignition curves....bliss for those that know how to use them properly..!
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Old 06-05-2019, 06:24 PM
  #2266  
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Greetings, My engine and I are new to this thread. I have been following for a while and appreciate everyone's experiences and inputs concerning this engine. I haven't run it yet, hoping to give it the best possible chance of success. I redrilled the timing sensor location for a 28 to 32 degree range, and am interested in the intake gases thru the crankcase housing mod for proper bottom end lubrication. Can anyone give me some input on the theory and necessary design . Thanks, Ed
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Old 06-08-2019, 02:01 PM
  #2267  
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Hey Ed,

Yeah lots of info here, lots of speculation too....but mostly helpful.
Depending on how new your engine is, you may have the 'new & improved' pistons and the cylinders....there are a few pics further back in the thread that Didier posted. The cylinders have had their heads changed to lower the compression, the cylinders are different now in that the mounting 'lugs' have more meat on them. Drilling the location of the sensor holes is one way to do the timing change, and I have heard recently that a good place to set the timing is around 34Deg as it gives a good balance of performance and longevity. Although if you have all the new components, then you may not have the problem.
For break in, I ran it as suggested in the book, and inverted the engine for a tank of break in, because it is so rich, the bottom cylinders dont really heat cycle. That was just my own preference, and others have tried various ways.

Morris Mini Motors sells a replacement prop hub which gives better options for the timing issues, he also sells a back plate redesign which eliminates the chances of hydro-locking, uses negative crankcase pressure as well. JieM posted a really good way to do the backplate design which is a little more elegant in my opinion as it forces the mixture into the crankcase, but it is not commercially available. He has supplied an .sti file with the design. Check post 2112

For what its worth, one of my engines I just drilled 6 x 4mm holes in the backplate, and it works fine. I think the other options from MMM and JieM are better though.

Remember, all of these are going to void your warranty....which is worhtless to me.

Ran mine in the SeaFury again today....and ran VERY well, seems to have settled in now, and even though ambient temps were in the mid 40C range, still went fine.

Pick your poison..

BTW, I am running Stihl HP in mine, at 30:1 with the negative crank mod and its holding up well. Good oil IMHO.

These things SIP petrol as well....did 2 x 8 min flights and probably used half of a 500ml tank....
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Old 06-08-2019, 05:37 PM
  #2268  
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Default Saito FG 60 -

Originally Posted by Didier View Post
Welcome to the Netherlands!
Yeah, I have the new piston/cylinder style Saito. The only mod I did was the MMM ignition ring.
I baffled the engine really well and the temps never exceed 135 degrees C. The engine runs really cool.
In my point of view the engine is the most happy between 6-7 KRPM.
I plan to fly mine just as stock. I purchased mine last November and it seems to run great after break in! I use Klotz oil at 20 to 1 and seems to run great! I have a question, how do I know if I have the new style cylinders and pistons in my engine without opening it up? Thank you and the Rare Bear is super nice!


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Old 06-09-2019, 01:27 AM
  #2269  
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Check out posts 2187 and 1849
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Old 06-09-2019, 01:00 PM
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Cathurga, thanks for your response. I purchased my FG60r3 and a FG84r3 at the same time back in march 2016 after watching some utube video's and Saito reeled me in hook,line and sinker. What a sound for my models ! I guess I should have researched all the reviews and video's before I leaped, but, I'm still not sorry I bought them. However, I became very reluctant to begin startup so I just oiled them up and stowed them away until hopefully Saito corrected any deficiencies that would be covered by my 3 year warranties. Reading about the attrition rate you guys have been experiencing over the past few years was a little disheartening ,but I felt rest assured I would be receiving a recall sooner or later . Well , 2 weeks before my warranty was up, I inquired about this with HH and they said if I was having any problems to send them the engine and they will honor the warranty. Well, there's nothing wrong with my 3 year old unused, never been started engines, so here we are. The FG84 I redrilled the timing sensor, installed the Saito FG90 bushed rod and intake manifold , because I feel that was the upgrade modification the 84 needed and the 90 got. The FG60 has the bushed rod , but the original pistons , which will stay, I redrilled the timing sensor for 28 to 32 degrees , and am going to try them both with these mods for initial runs. The 6 - 4mm holes that you drilled into the back cover sounds logical. They are seeing the back of the crank and rod with the nylon button centered , correct? Yes , your latest flying video's looked great, engine sounds happy! It's very reassuring that you guys, thru trial and effort and perseverance , have helped Saito's Radial Engine Program immensely and you deserve a raise ! I'll post results when I run them. Thanks again,Ed
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Old 06-10-2019, 02:44 AM
  #2271  
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Ed, I think we ALL got lured into this the same way, and when they run well, they sound great! Its quite difficult to 'size' a plane for these, as the combination of 4-stroke, gas and multi-cylinder means you are getting less power than a 50-55cc 2-stroke engine, but in the right application, they are good.
I would LOVE to know what the attrition rate is in real numbers. There are probably thousands and thousands of owners out there who have not had the problems the rest of us have had, although the fact that the FG90 replaced the FG84 pretty quickly, with the mods, and many of the mods were passed on to other models, means there was a problem to start with. With the new pistons for the FG60 and the new cylinders (BTW, the new pistons need their respective new rings as well, or they dont fit) it stands to reason that they KNOW that something is wrong, and are trying to fix it, but REST ASSURED you will not get a recall. With no disrepect to the culture, but if a recall did happen, someone would need to have died an 'honorable death'..
You have probably saved your engines just by doing the timing adjustment, but it will likely mean you dont get the best performance out of them, for that, the timing needs to be around 35-39 degrees from what I can deduce....but I am not one to seek performance over reliability...I will go with the latter. The problem is that the ignition curve is SET to advance to a max of 28-30De BTDC and a minimum of around 4-5Deg BTDC for starting. This means that to get 35-39 BTDC, the entire curve has to be shifted and then you get pre-ignition occuring in mid-range, and great power at the top end.... If the curve went from 4-5Deg on starting, all the way up to 35-39 deg, there would be a good range for easy starting, transition and top rpm.. At the moment, there is a compromise....
Some of the guys that bought from HH have got their units repaired and sent back to them, but I recall reading that they were told that the warranty was no longer valid after the repair...
Regarding the backplate, yeah, thats the plate that the nylon crankbush touches, just drilled some holes in it, and it seems to run fine, but I still think JieM's option is possibly the best design for this as it forces the mix into the crankcase, and then pulls it back through the holes to the intake tubes. Morris Mini Motors option is also a good one in that you are unlikely to EVER have a hydro-lock happen, and his is commercially available as an option. You can send him your plenum, he does the mods, and sends it back.
Anyway, I am happy to be the guine-pig for now, but its always great to hear other peoples opinions.....mine stink sometimes....lol

Last edited by cathurga; 06-10-2019 at 02:47 AM.
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Old 06-10-2019, 06:25 AM
  #2272  
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Default Saito FG60 carb trouble

I wanted to share something in case others have a similar issue. I was running my FG60 yesterday, preparing for an upcoming flyin, and really had the engine running good. I cut the engine off to go get a drink of water and when I came back out to start the engine, I started it and noticed it was running rough. It looked like I was near out of gas so I filled it back up. After that, all it would do was crank up and shut back down. After checking battery voltage, spark plug wires, etc, I figured this was a fuel issue. I pulled the engine off the plane so I could take a look at the carb. I found that I could not blow through the fuel inlet cleanly. It felt restricted so I began to tear the carb apart. After taking the pump and associated components apart, I blew everything out with compressed air. I put it back together but left the throttle barrel of so I could look at it. As I looked towards the high speed needle, I could see that the brass tube looked clogged. It looked so smooth on the end that I was wondering if it was suppose to be like that. I couldnít see it working like that so I unscrewed the high speed needle and set it aside. I took a flash light and looked through the brass tube but could not see out the other end. I took a small wire and ran through the high speed needle body and began to push out what looked to be crud. I sat this on a paper towel and blew the opening out with air. Now the light would shine all the way through. I assembled everything back together and now ready to try and run the engine. Iím sure this is why it wouldnít start and run.

I took a magnet and ran it across the paper towel where the crud was and low and behold the magnet sucked it off the paper towel. I still donít know what it was but it had a green tint to it under the magnifying glass. All I can think of is that something got sucked into the carb while running it on my driveway without the cowl installed. Definitely something to check if you are running good and all of a suddden loose gas flow to the carb. I use roto flow tanks and Iím wondering if somehow a piece of solder from inside the tank made it past my filtration. Sure is strange. I havenít tried to crank the motor as it got late last night but Iím sure this was the problem, Iíll report back after I try to run it again.

Debris in the bore of the high speed needle canít be good, it was completely stopped up.
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Old 06-10-2019, 11:11 AM
  #2273  
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Default Fuel filters

I doubt the debris came from the engine, more likely from everything before the carb. More reason to filter the gas going into your premix fuel tank, install a filter clunk in your airplane gas tank minimum. some put inline fuel filters between fuel tank & carb but you have to insure that connection doesn't suck air bubbles into your fuel line. I usually install the complete fuel delivery system from tank to carb,including clamps , then remove it all in one connected assembly, plug the tank vent & carb connection, submerge in water, then blow thru the the filler tubing to pressurize the system & check for air bubbles . Any bubbles = a leak which will suck air into the fuel line while engine is running & cause an erratic lean mixture = fix it.
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Old 06-10-2019, 11:45 AM
  #2274  
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When you say you looked at the HS needle, do you mean you were looking it from the side where the rotating barrel goes into the carb? If so, when you look there, and have the HS needle out, then you should see all the way through the brass tube that the HS needle goes into? (The same tube that has the slit in it, that the LS needle goes over?) If so, then I think I might have had the same trouble with mine at some stage, and I thought I had broken something so bought a new throttle body... probably coulda cleaned that out but I was too nervous to as I didnt want to pokey-pokey inside there...

As Ed says, I have a felt clunk in the bottom of my fuel can, I also have an inline filter on the filler pipe. I also ONLY use felt clunks in the planes fuel tank. Some have tried putting inline filters between the tank and the carb, but everytime I have done that, it seems to be a source of foaming so I avoid by have the other three filters in place....that should be enough. I prefer seeing the line from the tank to the carb with NO bubbles or air pockets in them.
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Old 06-10-2019, 03:45 PM
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Originally Posted by EFHANC View Post
I doubt the debris came from the engine, more likely from everything before the carb. More reason to filter the gas going into your premix fuel tank, install a filter clunk in your airplane gas tank minimum. some put inline fuel filters between fuel tank & carb but you have to insure that connection doesn't suck air bubbles into your fuel line. I usually install the complete fuel delivery system from tank to carb,including clamps , then remove it all in one connected assembly, plug the tank vent & carb connection, submerge in water, then blow thru the the filler tubing to pressurize the system & check for air bubbles . Any bubbles = a leak which will suck air into the fuel line while engine is running & cause an erratic lean mixture = fix it.
I think you meant the right thing here but generalized it a bit. You will always have air in your tank (from the vent line alone) which doesn't get sucked into the fuel line because it's submerged in the fuel. It's the part of the line that's not submerged that can't have holes in it to let air in, which is either the line itself or the connections on the barbs. If you have air bubbles in other areas, that's simply prone to fuel leakage.
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