ASP/MAGNUM FS400AR Rebuild/Overhaul
06-08-2013, 11:47 PM
#2351
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RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
Hey I'm about to do some stainless brazing. My sparrowhawk exhaust was just a manifold for a cannister ,yes loud! It snapped of just before the flexi/expansion section.I had it TIGed but broke again .Its so thin. Now I will try what A bloke in our club done ..cut the busted maniflod down and braze a heavier flex section (from Christian Traderswww.modelling.christiantraders.com.au/contents/en-us/d28_Flexible_Exhaust_Systems.html a 25.4mmdia.I will be able to get a super tght bend without stress. The braze is 45% silver with flux and yes can be used with a normal propane torch www.desertaircraft.com.au/shop/header-components/
I can get cheaper a my local engineering supplys ,but supply your own flux.
From what I've heard ,yes the flexi sections can rob power dramaticaly
To me its looks like its never been easier to make your own custom stainless headers. So I've got 2 cannisters and some headers coming from R2 hobbies on ebay to try chop up and make a twin setup for my Giant Stik.
I can get cheaper a my local engineering supplys ,but supply your own flux.
From what I've heard ,yes the flexi sections can rob power dramaticaly
To me its looks like its never been easier to make your own custom stainless headers. So I've got 2 cannisters and some headers coming from R2 hobbies on ebay to try chop up and make a twin setup for my Giant Stik.
06-08-2013, 11:57 PM
#2352
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RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
BJ a long time ago Bolly were making carbon fibre tuned pipes for glo boats. Apparently they would change a darker shade if it was lean or rich,not sure which! So they could handle heat ,but from a gas motor??
06-11-2013, 07:56 AM
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RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
Bit of a divergence from the 400 for a moment if I may, but I have been asked in the past how to tune twin carbs on V twin engines. Well guys, this is how!
http://www.youtube.com/watch?v=CnMbm...ature=youtu.be
Please note the engine in this video is brand new and had never been run prior to me taking this video. The slow run needles are a bit rich but I left them alone as the response was ok and it will need resetting inthe model anyway.Also note also the oil dripping off the head from the valve gear. No dry assembly here, Sanye please take note
http://www.youtube.com/watch?v=CnMbm...ature=youtu.be
Please note the engine in this video is brand new and had never been run prior to me taking this video. The slow run needles are a bit rich but I left them alone as the response was ok and it will need resetting inthe model anyway.Also note also the oil dripping off the head from the valve gear. No dry assembly here, Sanye please take note
06-11-2013, 10:06 PM
#2356
RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
ORIGINAL: Carosel43
Bit of a divergence from the 400 for a moment if I may, but I have been asked in the past how to tune twin carbs on V twin engines. Well guys, this is how!
http://www.youtube.com/watch?v=CnMbm...ature=youtu.be
Please note the engine in this video is brand new and had never been run prior to me taking this video. The slow run needles are a bit rich but I left them alone as the response was ok and it will need resetting in the model anyway. Also note also the oil dripping off the head from the valve gear. No dry assembly here, Sanye please take note
Bit of a divergence from the 400 for a moment if I may, but I have been asked in the past how to tune twin carbs on V twin engines. Well guys, this is how!
http://www.youtube.com/watch?v=CnMbm...ature=youtu.be
Please note the engine in this video is brand new and had never been run prior to me taking this video. The slow run needles are a bit rich but I left them alone as the response was ok and it will need resetting in the model anyway. Also note also the oil dripping off the head from the valve gear. No dry assembly here, Sanye please take note
Hi Jon
This is great! Thank you very much,
Artto
06-12-2013, 01:01 PM
#2358
RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
ORIGINAL: Carosel43
Hi Artto, I told you I would do this video eventually! I hope you find it helpful
Hi Artto, I told you I would do this video eventually! I hope you find it helpful
And not only I find it helpful but I'm sure there many others that feel the same. I think many will pay attention to how quick the engine respnds to change in needle setting. It's probably due to the carbs being attached without long intake tube. So you can apply full throttle and lean, lean out one carb at the time and then move to the other carb. My Saito FA-125a does not respond that quick to changes in HS needle setting but instead there is a quite long lag before you notice change in engine rpm. So if I did the tuning of my Saito in the same way I would easily pass the "sweet spot" and go further to lean of the optimum.
Another thing, many recommend using a tach to set the HS needles but you rely on your ears to determine change in engine tone. As I'm able to sing Neapolitan songs and opera arias I should be capable of doing the same
I'll be testing 10% nitro on my Laser 240v: I will set the carbs right in the same way as you did. I think I will also run, out of curiosity, the engine without the cline regulators, just to see if this makes any difference.
Ok I'll quite now as I'm getting of the original topic but thanks once again!
Artto
06-12-2013, 11:37 PM
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RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
Artto, with your specific installation I would leave your fuel system as it is. Due to the very high tank position you need the regulators and exhaust pressure to keep the fuel pressure constant with attitude change. I hope the video gives you a little more confidence in the tuning of your Yak. And I will do that cooling diagram eventually!
06-12-2013, 11:48 PM
#2360
RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
ORIGINAL: Carosel43
Artto, with your specific installation I would leave your fuel system as it is. Due to the very high tank position you need the regulators and exhaust pressure to keep the fuel pressure constant with attitude change. I hope the video gives you a little more confidence in the tuning of your Yak. And I will do that cooling diagram eventually!
Artto, with your specific installation I would leave your fuel system as it is. Due to the very high tank position you need the regulators and exhaust pressure to keep the fuel pressure constant with attitude change. I hope the video gives you a little more confidence in the tuning of your Yak. And I will do that cooling diagram eventually!
Yup I was thinking of just running the engine on the ground without the clines, just to see if this makes many change. As you say it won't work correctly in the air due to the tank position.
Your video does give me more confidence! And the same will apply to the cooling diagram
But please take you time, I know you'v got so many things going on at the same time..
06-12-2013, 11:58 PM
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RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
ORIGINAL: Carosel43
Bit of a divergence from the 400 for a moment if I may, but I have been asked in the past how to tune twin carbs on V twin engines. Well guys, this is how!
http://www.youtube.com/watch?v=CnMbm...ature=youtu.be
....
Bit of a divergence from the 400 for a moment if I may, but I have been asked in the past how to tune twin carbs on V twin engines. Well guys, this is how!
http://www.youtube.com/watch?v=CnMbm...ature=youtu.be
....
Crikey!
I always thought there was a bit of ~black magic~ involved.
You always see the I/C guys twiddling and fiddling and revving - no-one's ever explained in simple terms what they are doing.
Sooo... basically...
You start the engine up 'fat' (rich) on fuel - some manuals say 2 1/2 to 3 turns on the High Speed Needle... others may say 3 to 4 turns... etc.
Once the engine has warmed a bit, you bring it up to full throttle (measuring RPM if you can). Then you keep leaning the mixture out on the High Speed Needle (a little at a time and maybe wait a while till the RPM settles for some engines) until you see/hear max revs, then you back off (richen the mixture back up) 1/8th to 1/4 turn on the High Speed Needle. And that's it?
If so, you have forever simplified my understanding of the Voodoo that goes on between starting and flying a model engined aircraft.
Does the same method apply for 4 strokers as well as the 2 strokes?
BJ
06-13-2013, 03:20 AM
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RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
ORIGINAL: BJ64
You start the engine up 'fat' (rich) on fuel - some manuals say 2 1/2 to 3 turns on the High Speed Needle... others may say 3 to 4 turns... etc.
Once the engine has warmed a bit, you bring it up to full throttle (measuring RPM if you can). Then you keep leaning the mixture out on the High Speed Needle (a little at a time and maybe wait a while till the RPM settles for some engines) until you see/hear max revs, then you back off (richen the mixture back up) 1/8th to 1/4 turn on the High Speed Needle. And that's it?
You start the engine up 'fat' (rich) on fuel - some manuals say 2 1/2 to 3 turns on the High Speed Needle... others may say 3 to 4 turns... etc.
Once the engine has warmed a bit, you bring it up to full throttle (measuring RPM if you can). Then you keep leaning the mixture out on the High Speed Needle (a little at a time and maybe wait a while till the RPM settles for some engines) until you see/hear max revs, then you back off (richen the mixture back up) 1/8th to 1/4 turn on the High Speed Needle. And that's it?
What I will be doing soon is another video showing a single cylinder and I will setup the slow run as well as the high speed. Personally I do think Laser engines have the best throttle response going (due to the short intake) but the principal is the same for all engines. two strokes are a little more of a pain as they don't rev up as nicely as a 4 stroke, but again the basic principal is the same.
The method I personally use for Lasers (and I have used it on other engines with success) is:
Open needle to about 3 turns
Prime engine
Flip prop over to clear excess fuel
Set throttle to idle and put prop in the right position to start
glows on
tap prop backwards against compression (engine then fires, bounces in the correct direction blowing any crap out of the cylinder and inducting the correct amount of fuel for the next firing stroke)
once running disconnect glows and open up to 3000rpm
run for 30 secs
open up to 5000rpm
run for 30 secs
open to fullthrottle and set for max power. if the max point is correctly identified then there is no need to run 400rpm rich or anything like that. At most I will run 1/8 turn rich. my tuning increments are sometimes down to 1/32 of a turn (if im really being fancy about it) but for the most part its not worth being that accurate and is impossible with ASP/Saito/Enya as they have very course ratchets on their needles. OS tend to have fine ratchets and Laser don't have one at all. tuning the top end should take 15 secs or less. A good check for top end tuning is to throttle back and then open up again, if the RPM falls off after a few secs you are likely a little lean. One thing that is really fun when testing the new lasers (the 70s especially) is getting the tuning set at full power and just leaving it open while watching with a tacho. over a period of about 15 seconds the rpm slowly rise as the valves and ring bed down. its very satisfying to watch!
throttle to idle and check pickup
adjust idle needle as needed until pickup is satisfactory. usually I keep leaning until the engine hesitates on pickup and then I go back rich in small chunks until its spot on.
Now, this is my personal method and I have no doubt that other people have their own methods which no doubt work to their satisfaction. but if it stops raining today/tomorrow I will do another video showing a single and post it up. Also not all engines respond in the same way, for example trying to tune the 400 this way is not easy at all as the rpm fluctuates so much. My saito 450 also took upto20 seconds sometimes to respond to tuning changes so do be careful and check it holds power for 15 seconds or more before flying.
06-13-2013, 03:45 AM
#2363
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RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
I thought you flicked that thing clockwise to start it... now I know why 
At first, I just assumed it was a clockwise spinning motor (wouldn't be all that many about, would there?). As an aside, why do just about all Electrics and Fuelers run anticlockwise when viewed from the front?
I hear what you're saying re letting the ASP run a while longer after making a HSN change - they take a while for the RPM to equalise-out, yah?
Now... I'm waiting with baited breath for Pt2 - How to set the Low Speed Needle.
I suspect that this is the problem on a Tiger .91 single 2 stroker that I have - it starts easy, revs ok, then conks-out dead. We checked it's not fuel pickup problems. Someone remarked it's probably the LSN.
It'll be interesting to hear your thoughts.
Thanks heaps for the info so far - it'll be good to know what I'm doing and what I'm looking for in order to keep and engine running without going too lean...
BJ
At first, I just assumed it was a clockwise spinning motor (wouldn't be all that many about, would there?). As an aside, why do just about all Electrics and Fuelers run anticlockwise when viewed from the front?
I hear what you're saying re letting the ASP run a while longer after making a HSN change - they take a while for the RPM to equalise-out, yah?
Now... I'm waiting with baited breath for Pt2 - How to set the Low Speed Needle.
I suspect that this is the problem on a Tiger .91 single 2 stroker that I have - it starts easy, revs ok, then conks-out dead. We checked it's not fuel pickup problems. Someone remarked it's probably the LSN.
It'll be interesting to hear your thoughts.
Thanks heaps for the info so far - it'll be good to know what I'm doing and what I'm looking for in order to keep and engine running without going too lean...
BJ
06-13-2013, 04:20 AM
#2364
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RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
I will see if I can find a 2 stroke buried in a box somewhere and do a video of that. the problem with the 2 strokes is the LSN is harder to get at as usually they are deep inside the throttle barrel
Also that backwards flick trick is an old one. Saito even recommend it in their manuals. On my P40 and La7 I can start them by grabbing the spinner with thumb and finger and flipping it backwards. Much to the astonishment of those around me. But again, this is an old old trick that works equally well on 2 strokes, especially big 'uns
Also that backwards flick trick is an old one. Saito even recommend it in their manuals. On my P40 and La7 I can start them by grabbing the spinner with thumb and finger and flipping it backwards. Much to the astonishment of those around me. But again, this is an old old trick that works equally well on 2 strokes, especially big 'uns
06-13-2013, 05:12 AM
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RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
It's not so much getting to the LSN, it's more about how do you know it needs adjusting...and how do you go about adjusting it, Caro
BJ
BJ
06-13-2013, 06:37 AM
#2366
RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
ORIGINAL: Carosel43
It really is that simple..more or less. Theres a bit more to it if you really want the absolute max. for example in that video I tweak both needles as bit as I could hear a slight change in the engine. Its very subtle and I don't think the video even picks it up but it was enough for me to want to tweak it. in truth it wont matter a jot to 99% of people but I wanted to be sure it was right as its a test run and its got to be right before we send to the customer.
What I will be doing soon is another video showing a single cylinder and I will setup the slow run as well as the high speed. Personally I do think Laser engines have the best throttle response going (due to the short intake) but the principal is the same for all engines. two strokes are a little more of a pain as they don't rev up as nicely as a 4 stroke, but again the basic principal is the same.
The method I personally use for Lasers (and I have used it on other engines with success) is:
Open needle to about 3 turns
Prime engine
Flip prop over to clear excess fuel
Set throttle to idle and put prop in the right position to start
glows on
tap prop backwards against compression (engine then fires, bounces in the correct direction blowing any crap out of the cylinder and inducting the correct amount of fuel for the next firing stroke)
once running disconnect glows and open up to 3000rpm
run for 30 secs
open up to 5000rpm
run for 30 secs
open to full throttle and set for max power. if the max point is correctly identified then there is no need to run 400rpm rich or anything like that. At most I will run 1/8 turn rich. my tuning increments are sometimes down to 1/32 of a turn (if im really being fancy about it) but for the most part its not worth being that accurate and is impossible with ASP/Saito/Enya as they have very course ratchets on their needles. OS tend to have fine ratchets and Laser don't have one at all. tuning the top end should take 15 secs or less. A good check for top end tuning is to throttle back and then open up again, if the RPM falls off after a few secs you are likely a little lean. One thing that is really fun when testing the new lasers (the 70s especially) is getting the tuning set at full power and just leaving it open while watching with a tacho. over a period of about 15 seconds the rpm slowly rise as the valves and ring bed down. its very satisfying to watch!
throttle to idle and check pickup
adjust idle needle as needed until pickup is satisfactory. usually I keep leaning until the engine hesitates on pickup and then I go back rich in small chunks until its spot on.
Now, this is my personal method and I have no doubt that other people have their own methods which no doubt work to their satisfaction. but if it stops raining today/tomorrow I will do another video showing a single and post it up. Also not all engines respond in the same way, for example trying to tune the 400 this way is not easy at all as the rpm fluctuates so much. My saito 450 also took upto 20 seconds sometimes to respond to tuning changes so do be careful and check it holds power for 15 seconds or more before flying.
ORIGINAL: BJ64
You start the engine up 'fat' (rich) on fuel - some manuals say 2 1/2 to 3 turns on the High Speed Needle... others may say 3 to 4 turns... etc.
Once the engine has warmed a bit, you bring it up to full throttle (measuring RPM if you can). Then you keep leaning the mixture out on the High Speed Needle (a little at a time and maybe wait a while till the RPM settles for some engines) until you see/hear max revs, then you back off (richen the mixture back up) 1/8th to 1/4 turn on the High Speed Needle. And that's it?
You start the engine up 'fat' (rich) on fuel - some manuals say 2 1/2 to 3 turns on the High Speed Needle... others may say 3 to 4 turns... etc.
Once the engine has warmed a bit, you bring it up to full throttle (measuring RPM if you can). Then you keep leaning the mixture out on the High Speed Needle (a little at a time and maybe wait a while till the RPM settles for some engines) until you see/hear max revs, then you back off (richen the mixture back up) 1/8th to 1/4 turn on the High Speed Needle. And that's it?
What I will be doing soon is another video showing a single cylinder and I will setup the slow run as well as the high speed. Personally I do think Laser engines have the best throttle response going (due to the short intake) but the principal is the same for all engines. two strokes are a little more of a pain as they don't rev up as nicely as a 4 stroke, but again the basic principal is the same.
The method I personally use for Lasers (and I have used it on other engines with success) is:
Open needle to about 3 turns
Prime engine
Flip prop over to clear excess fuel
Set throttle to idle and put prop in the right position to start
glows on
tap prop backwards against compression (engine then fires, bounces in the correct direction blowing any crap out of the cylinder and inducting the correct amount of fuel for the next firing stroke)
once running disconnect glows and open up to 3000rpm
run for 30 secs
open up to 5000rpm
run for 30 secs
open to full throttle and set for max power. if the max point is correctly identified then there is no need to run 400rpm rich or anything like that. At most I will run 1/8 turn rich. my tuning increments are sometimes down to 1/32 of a turn (if im really being fancy about it) but for the most part its not worth being that accurate and is impossible with ASP/Saito/Enya as they have very course ratchets on their needles. OS tend to have fine ratchets and Laser don't have one at all. tuning the top end should take 15 secs or less. A good check for top end tuning is to throttle back and then open up again, if the RPM falls off after a few secs you are likely a little lean. One thing that is really fun when testing the new lasers (the 70s especially) is getting the tuning set at full power and just leaving it open while watching with a tacho. over a period of about 15 seconds the rpm slowly rise as the valves and ring bed down. its very satisfying to watch!
throttle to idle and check pickup
adjust idle needle as needed until pickup is satisfactory. usually I keep leaning until the engine hesitates on pickup and then I go back rich in small chunks until its spot on.
Now, this is my personal method and I have no doubt that other people have their own methods which no doubt work to their satisfaction. but if it stops raining today/tomorrow I will do another video showing a single and post it up. Also not all engines respond in the same way, for example trying to tune the 400 this way is not easy at all as the rpm fluctuates so much. My saito 450 also took upto 20 seconds sometimes to respond to tuning changes so do be careful and check it holds power for 15 seconds or more before flying.
I think it's good to remind us all that you do not use muffler pressure on Laser engines, hence no need to richen the HS by the norm 200-400 rpm from the peak which you must do with the engines that you use muffler pressure. The reason is, the pressure inside the tank decreases along with the decreasing amount of fuel inside the tank. As a consquence of this the engine goes too lean if you set the HS needle to peak rpm at full tank
As a
06-13-2013, 07:41 AM
#2368
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RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
I have run pressurised engines (OS, Saito,ASP,SC,Enya and lasers) for many years without issue. I have never run them rich. just tune for max power and fly. The pressure in the tank should remain pretty constant, the only reason they appear to lean off is as the tank level drops any gravity assistance is reduced. this clearly all depends on tank position though.
The primary reason for the recommendation to run 400rpm rich or whatever is because people either go right past the peak in search of more power or do not give the engine sufficient time to react to tuning changes and so end up lean in the air. I have done this myself with the 400 as I forgot just how long it takes for tuning changes on the 400 to take effect. Also different engines have different peak characteristics. Laser have a noticeable peak and fall off (apart from the 180 which is less marked). My enya 120 had a peak and die mentality so you had to be right on the money. One click leaner and it died, YS are similar but at least they let you know when you have gone too far. Nitro further clouds the issue as the peak becomes much broader.
The primary reason for the recommendation to run 400rpm rich or whatever is because people either go right past the peak in search of more power or do not give the engine sufficient time to react to tuning changes and so end up lean in the air. I have done this myself with the 400 as I forgot just how long it takes for tuning changes on the 400 to take effect. Also different engines have different peak characteristics. Laser have a noticeable peak and fall off (apart from the 180 which is less marked). My enya 120 had a peak and die mentality so you had to be right on the money. One click leaner and it died, YS are similar but at least they let you know when you have gone too far. Nitro further clouds the issue as the peak becomes much broader.
06-13-2013, 10:08 AM
#2369
RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
ORIGINAL: Carosel43
I have run pressurised engines (OS, Saito,ASP,SC,Enya and lasers) for many years without issue. I have never run them rich. just tune for max power and fly. The pressure in the tank should remain pretty constant, the only reason they appear to lean off is as the tank level drops any gravity assistance is reduced. this clearly all depends on tank position though.
The primary reason for the recommendation to run 400rpm rich or whatever is because people either go right past the peak in search of more power or do not give the engine sufficient time to react to tuning changes and so end up lean in the air. I have done this myself with the 400 as I forgot just how long it takes for tuning changes on the 400 to take effect. Also different engines have different peak characteristics. Laser have a noticeable peak and fall off (apart from the 180 which is less marked). My enya 120 had a peak and die mentality so you had to be right on the money. One click leaner and it died, YS are similar but at least they let you know when you have gone too far. Nitro further clouds the issue as the peak becomes much broader.
I have run pressurised engines (OS, Saito,ASP,SC,Enya and lasers) for many years without issue. I have never run them rich. just tune for max power and fly. The pressure in the tank should remain pretty constant, the only reason they appear to lean off is as the tank level drops any gravity assistance is reduced. this clearly all depends on tank position though.
The primary reason for the recommendation to run 400rpm rich or whatever is because people either go right past the peak in search of more power or do not give the engine sufficient time to react to tuning changes and so end up lean in the air. I have done this myself with the 400 as I forgot just how long it takes for tuning changes on the 400 to take effect. Also different engines have different peak characteristics. Laser have a noticeable peak and fall off (apart from the 180 which is less marked). My enya 120 had a peak and die mentality so you had to be right on the money. One click leaner and it died, YS are similar but at least they let you know when you have gone too far. Nitro further clouds the issue as the peak becomes much broader.
06-13-2013, 10:19 AM
#2370
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RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
That's a strange one..lol. if the tuning is right it should in theory run at the same rpm no matter what, although if you are a touch rich at full tanks to prevent a lean cut at half tanks that might explain it. The thing is with the larger carbs saitos do not have as stronger a fuel draw as some other brands
06-13-2013, 11:12 AM
#2371
RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
ORIGINAL: Carosel43
That's a strange one..lol. if the tuning is right it should in theory run at the same rpm no matter what, although if you are a touch rich at full tanks to prevent a lean cut at half tanks that might explain it. The thing is with the larger carbs saitos do not have as stronger a fuel draw as some other brands
That's a strange one..lol. if the tuning is right it should in theory run at the same rpm no matter what, although if you are a touch rich at full tanks to prevent a lean cut at half tanks that might explain it. The thing is with the larger carbs saitos do not have as stronger a fuel draw as some other brands
06-14-2013, 03:46 AM
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RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
ORIGINAL: BJ64
When do we find out how to set the LSN..? *hint hint*...
BJ
When do we find out how to set the LSN..? *hint hint*...
BJ
lucky for you I was able to get out today and fire up my 150. I deliberately put the needles very rich to represent an engine that's had some basic settings applied. in this case it was about 6 turns on the slow run and 3 on the main (other engines will have different basic settings).
Anyway I fired it up and set the top end as before (lean off pretty quickly until close and then slowly to the max), then I throttle back and there are clues about the bottom end tuning. For a start its very lumpy, lots of smoke and is not really that happy below 2500rpm. The rpm also dances around and throttle response is poor.
so, I lean out the slow run in quite large 1/3 turn chunks and check the pickup as I go. Eventually the engine bogs and wont accelerate. That means im too lean. Other clues for a lean slow run include a fast but smooth rpm that dies abruptly if throttled back further in an attempt to drop the rpm, difficulty starting (the engine picks up on the prime and then stops or just pops and farts when driven by a starter), excessive throttle opening to allow starting.
from the lean setting I slowly open the needle in much smaller 1/8 turn increments until im really close, then its down to really small 1/32 tweaks to get it perfect (you don't have to be that anal if you don't want to). I then reset the high speed needle as the slow run has an effect on it.
When correctly tuned the throttle response is much better, idle rpm slower and smotherthe whole engine is more reliable and there is less smoke blowing about.
http://www.youtube.com/watch?v=DaeLy...ature=youtu.be
Enjoy
p.s. I also have another video of a twin and I set the slow runs on that as well. Its a part work as the engine stopped twice and needed to be restarted. As its not strictly relevant here I wont post it unless there is significant interest. if anyone wants it for their own personal use let me know and I will send it over (after I knit it together)
And yes I know my test bench is filthy and my prop has chunks out of it, but that's my benchmark prop and the state of the bench matters not as the pipes are nice and clean!
06-14-2013, 06:44 AM
#2374
RE: ASP/MAGNUM FS400AR Rebuild/Overhaul
Hi Jon
I tried to watch the video but it says "it's being processed" (or something)?
I think these video tutorials are of a very high value and I think "club Laser might be a good subforum for them, too.
However, as the tutorials refer to appropriate tuning methods in general one should not limit this information to Laser engine enthusiasts, only.
So I do not think you are breaking any rules if you post the other twin videos here, too. At least I would like to see them here
Artto
I tried to watch the video but it says "it's being processed" (or something)?
I think these video tutorials are of a very high value and I think "club Laser might be a good subforum for them, too.
However, as the tutorials refer to appropriate tuning methods in general one should not limit this information to Laser engine enthusiasts, only.
So I do not think you are breaking any rules if you post the other twin videos here, too. At least I would like to see them here
Artto