Oil leaking out - Splattered Cowl
01-28-2007, 05:16 AM
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Oil leaking out - Splattered Cowl
I've been flying my Funtana yesterday with a new Thunder Tiger 91 Four Stroke engine in it.
Coming to the clean up afterwards, theres quite a lot of oil splattered around the inside of the front of the cowl.
It looks to be coming from behined the prop driver washer where the front crankcase bearing is ?
I've not had a fully cowled engine before, so wouldn't have noticed if oil had splattered out of any other of my planes engines.
Is this normal ?
The engine is brand new out the box, and now has 3 tanks of fuel through it.
Coming to the clean up afterwards, theres quite a lot of oil splattered around the inside of the front of the cowl.
It looks to be coming from behined the prop driver washer where the front crankcase bearing is ?
I've not had a fully cowled engine before, so wouldn't have noticed if oil had splattered out of any other of my planes engines.
Is this normal ?
The engine is brand new out the box, and now has 3 tanks of fuel through it.
01-28-2007, 06:12 AM
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RE: Oil leaking out - Splattered Cowl
Check to see that the crankcase vent nipple is clear.
If you have put a piece of fuel tube on the crankcase vent, how long is it ?
If it's too long oil will build up in the crankcase and then might come out of the front bearing. If all appears to be ok then the shield on the front bearing has failed. This won't do any harm though other than cover your model with goo.
Good luck
If you have put a piece of fuel tube on the crankcase vent, how long is it ?
If it's too long oil will build up in the crankcase and then might come out of the front bearing. If all appears to be ok then the shield on the front bearing has failed. This won't do any harm though other than cover your model with goo.
Good luck
01-28-2007, 06:38 AM
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RE: Oil leaking out - Splattered Cowl
Thanks.
The nipple appears to be clear, as you can hear air coming out of it, or going into it as you turn the engine over by hand.
I have tried it with and without a bit of fuel tube on it, as I first thought that it might have been the nipple that was chucking all the oil out to start off with, so I put some tube on their and placed it so that it would chuck the oil clear of the plane.
But after flying, the oil splatter was still the same.
If the bearing is knackered then it's under warranty anyway, as it's brand new, so it can go back if thats the case.
The nipple appears to be clear, as you can hear air coming out of it, or going into it as you turn the engine over by hand.
I have tried it with and without a bit of fuel tube on it, as I first thought that it might have been the nipple that was chucking all the oil out to start off with, so I put some tube on their and placed it so that it would chuck the oil clear of the plane.
But after flying, the oil splatter was still the same.
If the bearing is knackered then it's under warranty anyway, as it's brand new, so it can go back if thats the case.
01-28-2007, 06:47 AM
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RE: Oil leaking out - Splattered Cowl
Hi
I wouldn't get too excited about sending that engine back just yet. You really need to wait until it's properly run in and you will most likely find that the problem goes away. At the moment you're getting a lot more blow-by than you will once run in. A little oil from the front bearing is nothing to worry about anyway as it shows your bottom end is getting enough lubrication.
Dave :^)
I wouldn't get too excited about sending that engine back just yet. You really need to wait until it's properly run in and you will most likely find that the problem goes away. At the moment you're getting a lot more blow-by than you will once run in. A little oil from the front bearing is nothing to worry about anyway as it shows your bottom end is getting enough lubrication.
Dave :^)
01-28-2007, 09:31 AM
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RE: Oil leaking out - Splattered Cowl
Thanks for the advice Dave, I'll have to see what it's like later on then 
How is it possible that it could leak out less oil later on after running it in ?
Craig.
How is it possible that it could leak out less oil later on after running it in ?
Craig.
01-28-2007, 10:18 AM
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RE: Oil leaking out - Splattered Cowl
ORIGINAL: Chocks_Away
Thanks for the advice Dave, I'll have to see what it's like later on then
How is it possible that it could leak out less oil later on after running it in ?
Craig.
Thanks for the advice Dave, I'll have to see what it's like later on then
How is it possible that it could leak out less oil later on after running it in ?
Craig.
Cheers,
Chip
01-28-2007, 05:27 PM
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RE: Oil leaking out - Splattered Cowl
Did you install the choke assembly? The choke assembly has a venturi built on it which helps to prevent fuel from spitting out the carb and into your cowl. As mentioned before when the ring seats there will be less blow by past the ring and out the vent tube.
01-29-2007, 12:25 PM
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RE: Oil leaking out - Splattered Cowl
ORIGINAL: MrMotor
Did you install the choke assembly? The choke assembly has a venturi built on it which helps to prevent fuel from spitting out the carb and into your cowl. As mentioned before when the ring seats there will be less blow by past the ring and out the vent tube.
Did you install the choke assembly? The choke assembly has a venturi built on it which helps to prevent fuel from spitting out the carb and into your cowl. As mentioned before when the ring seats there will be less blow by past the ring and out the vent tube.
(but the carb is no where near where the splatter is anyway.)
01-29-2007, 12:26 PM
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RE: Oil leaking out - Splattered Cowl
ORIGINAL: Ed Cregger
Also, as the engine breaks-in, you will be leaning the mixture needles in order to get it to run well. Less fuel means less oil spread over your model.
Ed Cregger
Also, as the engine breaks-in, you will be leaning the mixture needles in order to get it to run well. Less fuel means less oil spread over your model.
Ed Cregger
I'm only running it rich by a 1/4 turn now from the optimum setting.
01-29-2007, 03:59 PM
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RE: Oil leaking out - Splattered Cowl
ORIGINAL: Chocks_Away
Yeah, thats true, but I'm more or less at final settings anyway now.
I'm only running it rich by a 1/4 turn now from the optimum setting.
ORIGINAL: Ed Cregger
Also, as the engine breaks-in, you will be leaning the mixture needles in order to get it to run well. Less fuel means less oil spread over your model.
Ed Cregger
Also, as the engine breaks-in, you will be leaning the mixture needles in order to get it to run well. Less fuel means less oil spread over your model.
Ed Cregger
I'm only running it rich by a 1/4 turn now from the optimum setting.
01-29-2007, 06:49 PM
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RE: Oil leaking out - Splattered Cowl
Hiya, my TT91 is in a Funtana X50.
It's a bit on the big side to be putting in a 40 sized Telemaster trainer though isn't it ? [X(]
I'm only running mine on 5% nitro, and after seeing the performance it gives, I see no need to increase it.
It will go vertical on only 1/2 throttle, so the hover will only be just below that anyway.
It has plenty of pull out power, and full throttle sees it going straight up at a fair rate of knotts, so isn't going to be needed much, and when it is, it will only be in short bursts anyhow.
I went for a bigger engine than I actually needed, so I know it will handle what I want it to do with ease
So, it should last a good long while for what I will be demanding from it, as it shouldn't be under much stress.
It's a bit on the big side to be putting in a 40 sized Telemaster trainer though isn't it ? [X(]
I'm only running mine on 5% nitro, and after seeing the performance it gives, I see no need to increase it.
It will go vertical on only 1/2 throttle, so the hover will only be just below that anyway.
It has plenty of pull out power, and full throttle sees it going straight up at a fair rate of knotts, so isn't going to be needed much, and when it is, it will only be in short bursts anyhow.
I went for a bigger engine than I actually needed, so I know it will handle what I want it to do with ease
So, it should last a good long while for what I will be demanding from it, as it shouldn't be under much stress.
01-30-2007, 01:41 AM
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RE: Oil leaking out - Splattered Cowl
The SR is a Senior Telmaster around a 96" wing span at 12lbs. She is a floater with that large wing. I was wondering about the Funtana 50 as a possible replacement for my UCD 60 it's starting to show it's age.......LOL I crashed my UCD in my car......NO inside my car....hehehe a lady pulled out in front of me putting on her makeup , and the quick stop slammed my heavy flight box into the tail section crushing it badly. I broke the tail of a while back on landing so the Tail section is becoming a big PIA if you know what I mean.
Thanks sounds like the Fun 50 could get me off the 30%
Thanks sounds like the Fun 50 could get me off the 30%
01-30-2007, 12:31 PM
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RE: Oil leaking out - Splattered Cowl
Ahh, I didn't realise that you can get a larger Telemaster, now thats a different story in a 12lb plane
My Funtana X50 weighs 6lb 10oz without fuel, so you can imagine the power increase you'd get from that engine on a plane almost half the weight [sm=lol.gif]
Yeah, it probably would be a good choice for a replacement to the UCD.
[X(] That is a right pain in the ass, even more so if you were on your way out to go and fly [:@]
Not as bad if your were returning home after a session, but still very annoying none the less [&:]
Yeah, I see no need for the more expensive 30%
I'd only consider using 10% at the most, and thats only if I was experiencing any running/tickover problems.
My Funtana X50 weighs 6lb 10oz without fuel, so you can imagine the power increase you'd get from that engine on a plane almost half the weight [sm=lol.gif]
Yeah, it probably would be a good choice for a replacement to the UCD.
[X(] That is a right pain in the ass, even more so if you were on your way out to go and fly [:@]
Not as bad if your were returning home after a session, but still very annoying none the less [&:]
Yeah, I see no need for the more expensive 30%
I'd only consider using 10% at the most, and thats only if I was experiencing any running/tickover problems.
01-30-2007, 06:26 PM
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RE: Oil leaking out - Splattered Cowl
Do you have enough fuel line on the vent to take the oil out of the bottom of the cowl, up to 6 inches won't hurt a thing and it would take a whole lot more than that to make oil come out of the front bearing.
01-31-2007, 11:23 AM
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RE: Oil leaking out - Splattered Cowl
ORIGINAL: Checklst
My TT91 pulled 11lb 8oz on a static pull ,that's not a bad ratio for hoover...... in a 6.8 LB air frame
My TT91 pulled 11lb 8oz on a static pull ,that's not a bad ratio for hoover...... in a 6.8 LB air frame
ORIGINAL: Hobbsy
Do you have enough fuel line on the vent to take the oil out of the bottom of the cowl, up to 6 inches won't hurt a thing and it would take a whole lot more than that to make oil come out of the front bearing.
Do you have enough fuel line on the vent to take the oil out of the bottom of the cowl, up to 6 inches won't hurt a thing and it would take a whole lot more than that to make oil come out of the front bearing.
After the flight, there was no oil in the pipe at all.
The pipe was clear of any obstructions. and you could hear the air coming out of the end of the pipe no problem.
ORIGINAL: Sport_Pilot
Could the tube from the vent have a leak in it?
Could the tube from the vent have a leak in it?
01-31-2007, 08:52 PM
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RE: Oil leaking out - Splattered Cowl
chocks_Away A retired Pharmacist at our field purchased an electronic hand held scale. I don't remember the brand, but he checked it's accuracy with his brass scale weights. He is compiling more than a few numbers on a lot of different motors in the last 3months. He records the static thrust at max rpm, engine type and fuel type. I have used his scale and I kept a little more data on my engines like Prop Pitch.............. I am think of using his pull scale to set my throttle stick position to match a (hover rpm) example would be a plane that hovers at 3/4 throttle but you would like the same RPM at a Half throttle stick position........it just seem easier for me to find the 1/2 throttle position.
His only request is that you fly your plane and after landing you attach it to his scale and static pull without needle adjustment(not an over lean not flyable setting)
His data as a whole has shown what a lot of us have thought for some time that 2 cycle and 4 cycle are (thrust wise) are vary equal in the same CC engine size. Last time I looked at his chart the OS 120AX 2c had a 2 oz lower(static thrust pull) than the Satio 125FS ,this makes perfect since the CC is slightly larger on the Satio. Most ALL engines are staying with in the rule of (CC engine size rules) CC is more of a determining factor for power than what type of motor(2c vers4c)
THE ONLY ENGINES to break this RULE is some of the YS 4strokes so far 2 of their engines 140,63's are pulling well above the 2stroke counter parts of equal CC engine size. Example 4 OS 160's 2C all pulled around 16.1 lbs with one OS at 17.3 lbs on 30% nitro, only 2 YS140FS tested so far both were on 30% 17.6 and 17.12 lbs thrust, considering the differences in CC engine size this is quite a large gap between the 2. NOW I'm sure that does not supprise YS folks but the next has most of us at our field going Hummmmmmmmmmmmm the 4 YS 110's tested so far all on 30% stayed within their CC class go figure. I'm sure in the spring(good weather) we'll get a lot more 110s in the mix so maybe the data will swing up (above their CC class) like their brothers the 63 and 140 who knows.
Like I said above we don't tweak......change props........fuel ect.........we just fly, do a thrust pull write down the data and REFER TO IT when someone ASK...WHAT ENGINE will hover my 12lb plane the best. This Data has maybe 30 various engines so far so I hope no one takes it as gospel and starts a WAR over it.......it just shows simple trends.
His only request is that you fly your plane and after landing you attach it to his scale and static pull without needle adjustment(not an over lean not flyable setting)
His data as a whole has shown what a lot of us have thought for some time that 2 cycle and 4 cycle are (thrust wise) are vary equal in the same CC engine size. Last time I looked at his chart the OS 120AX 2c had a 2 oz lower(static thrust pull) than the Satio 125FS ,this makes perfect since the CC is slightly larger on the Satio. Most ALL engines are staying with in the rule of (CC engine size rules) CC is more of a determining factor for power than what type of motor(2c vers4c)
THE ONLY ENGINES to break this RULE is some of the YS 4strokes so far 2 of their engines 140,63's are pulling well above the 2stroke counter parts of equal CC engine size. Example 4 OS 160's 2C all pulled around 16.1 lbs with one OS at 17.3 lbs on 30% nitro, only 2 YS140FS tested so far both were on 30% 17.6 and 17.12 lbs thrust, considering the differences in CC engine size this is quite a large gap between the 2. NOW I'm sure that does not supprise YS folks but the next has most of us at our field going Hummmmmmmmmmmmm the 4 YS 110's tested so far all on 30% stayed within their CC class go figure. I'm sure in the spring(good weather) we'll get a lot more 110s in the mix so maybe the data will swing up (above their CC class) like their brothers the 63 and 140 who knows.
Like I said above we don't tweak......change props........fuel ect.........we just fly, do a thrust pull write down the data and REFER TO IT when someone ASK...WHAT ENGINE will hover my 12lb plane the best. This Data has maybe 30 various engines so far so I hope no one takes it as gospel and starts a WAR over it.......it just shows simple trends.
02-01-2007, 01:21 PM
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RE: Oil leaking out - Splattered Cowl
Well, thats a simple & effective method of doing it.
I have heard of people doing it with electric motors on a test bed to test the thrust, but not on a large IC model.
I had a feeling it would be done the same way as electric motors (with a set of scales) but I would have thought that it would be very awkward to do with a large plane.
Anyway, 2 stroke thrust Vs 4 stroke thrust CC for CC is about the same you say ?
Well, the only difference that there will be for sure then is that the 2 strokes will produce their torque at top rpm, whereas the 4 strokes will produce it at a low rpm.
I have heard of people doing it with electric motors on a test bed to test the thrust, but not on a large IC model.
I had a feeling it would be done the same way as electric motors (with a set of scales) but I would have thought that it would be very awkward to do with a large plane.
Anyway, 2 stroke thrust Vs 4 stroke thrust CC for CC is about the same you say ?
Well, the only difference that there will be for sure then is that the 2 strokes will produce their torque at top rpm, whereas the 4 strokes will produce it at a low rpm.
02-01-2007, 02:32 PM
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RE: Oil leaking out - Splattered Cowl
ORIGINAL: Chocks_Away
Yeah, thats true, but I'm more or less at final settings anyway now.
I'm only running it rich by a 1/4 turn now from the optimum setting.
ORIGINAL: Ed Cregger
Also, as the engine breaks-in, you will be leaning the mixture needles in order to get it to run well. Less fuel means less oil spread over your model.
Ed Cregger
Also, as the engine breaks-in, you will be leaning the mixture needles in order to get it to run well. Less fuel means less oil spread over your model.
Ed Cregger
I'm only running it rich by a 1/4 turn now from the optimum setting.
---------------
Nope. If you only have a few tanks of fuel through it so far, the engine will loosen up with more use, requiring you to reset (lean) the mixtures over time.
Ed Cregger
02-01-2007, 02:40 PM
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RE: Oil leaking out - Splattered Cowl
ORIGINAL: Checklst
chocks_Away A retired Pharmacist at our field purchased an electronic hand held scale. I don't remember the brand, but he checked it's accuracy with his brass scale weights. He is compiling more than a few numbers on a lot of different motors in the last 3months. He records the static thrust at max rpm, engine type and fuel type. I have used his scale and I kept a little more data on my engines like Prop Pitch.............. I am think of using his pull scale to set my throttle stick position to match a (hover rpm) example would be a plane that hovers at 3/4 throttle but you would like the same RPM at a Half throttle stick position........it just seem easier for me to find the 1/2 throttle position.
His only request is that you fly your plane and after landing you attach it to his scale and static pull without needle adjustment(not an over lean not flyable setting)
His data as a whole has shown what a lot of us have thought for some time that 2 cycle and 4 cycle are (thrust wise) are vary equal in the same CC engine size. Last time I looked at his chart the OS 120AX 2c had a 2 oz lower(static thrust pull) than the Satio 125FS ,this makes perfect since the CC is slightly larger on the Satio. Most ALL engines are staying with in the rule of (CC engine size rules) CC is more of a determining factor for power than what type of motor(2c vers4c)
THE ONLY ENGINES to break this RULE is some of the YS 4strokes so far 2 of their engines 140,63's are pulling well above the 2stroke counter parts of equal CC engine size. Example 4 OS 160's 2C all pulled around 16.1 lbs with one OS at 17.3 lbs on 30% nitro, only 2 YS140FS tested so far both were on 30% 17.6 and 17.12 lbs thrust, considering the differences in CC engine size this is quite a large gap between the 2. NOW I'm sure that does not supprise YS folks but the next has most of us at our field going Hummmmmmmmmmmmm the 4 YS 110's tested so far all on 30% stayed within their CC class go figure. I'm sure in the spring(good weather) we'll get a lot more 110s in the mix so maybe the data will swing up (above their CC class) like their brothers the 63 and 140 who knows.
Like I said above we don't tweak......change props........fuel ect.........we just fly, do a thrust pull write down the data and REFER TO IT when someone ASK...WHAT ENGINE will hover my 12lb plane the best. This Data has maybe 30 various engines so far so I hope no one takes it as gospel and starts a WAR over it.......it just shows simple trends.
chocks_Away A retired Pharmacist at our field purchased an electronic hand held scale. I don't remember the brand, but he checked it's accuracy with his brass scale weights. He is compiling more than a few numbers on a lot of different motors in the last 3months. He records the static thrust at max rpm, engine type and fuel type. I have used his scale and I kept a little more data on my engines like Prop Pitch.............. I am think of using his pull scale to set my throttle stick position to match a (hover rpm) example would be a plane that hovers at 3/4 throttle but you would like the same RPM at a Half throttle stick position........it just seem easier for me to find the 1/2 throttle position.
His only request is that you fly your plane and after landing you attach it to his scale and static pull without needle adjustment(not an over lean not flyable setting)
His data as a whole has shown what a lot of us have thought for some time that 2 cycle and 4 cycle are (thrust wise) are vary equal in the same CC engine size. Last time I looked at his chart the OS 120AX 2c had a 2 oz lower(static thrust pull) than the Satio 125FS ,this makes perfect since the CC is slightly larger on the Satio. Most ALL engines are staying with in the rule of (CC engine size rules) CC is more of a determining factor for power than what type of motor(2c vers4c)
THE ONLY ENGINES to break this RULE is some of the YS 4strokes so far 2 of their engines 140,63's are pulling well above the 2stroke counter parts of equal CC engine size. Example 4 OS 160's 2C all pulled around 16.1 lbs with one OS at 17.3 lbs on 30% nitro, only 2 YS140FS tested so far both were on 30% 17.6 and 17.12 lbs thrust, considering the differences in CC engine size this is quite a large gap between the 2. NOW I'm sure that does not supprise YS folks but the next has most of us at our field going Hummmmmmmmmmmmm the 4 YS 110's tested so far all on 30% stayed within their CC class go figure. I'm sure in the spring(good weather) we'll get a lot more 110s in the mix so maybe the data will swing up (above their CC class) like their brothers the 63 and 140 who knows.
Like I said above we don't tweak......change props........fuel ect.........we just fly, do a thrust pull write down the data and REFER TO IT when someone ASK...WHAT ENGINE will hover my 12lb plane the best. This Data has maybe 30 various engines so far so I hope no one takes it as gospel and starts a WAR over it.......it just shows simple trends.
---------------
This only works if the two-stroke is saddled down with a huge prop and is running out of its design range. Put a normal sized prop on the two-stroke and it will thoroughly kick the snot out of a four-stroke of equal displacement. Don't believe me? Watch the motorcycle races. You'll see that they have to give the four-strokes twice the displacement to stay with the itty-bitty two-strokes.
This whole static thrust thing is baloney anyway. I don't fly my models static. Do you? I find it to be much more fun to have the model actually leave the ground and fly around through the air.
Ed Cregger
02-01-2007, 05:18 PM
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RE: Oil leaking out - Splattered Cowl
If you only have a few tanks of fuel through it so far, the engine will loosen up with more use, requiring you to reset (lean) the mixtures over time.
Ed Cregger
I didn't realise that
02-01-2007, 10:27 PM
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RE: Oil leaking out - Splattered Cowl
ORIGINAL: Chocks_Away
If you only have a few tanks of fuel through it so far, the engine will loosen up with more use, requiring you to reset (lean) the mixtures over time.
Ed Cregger
Yeh ?
I didn't realise that
If you only have a few tanks of fuel through it so far, the engine will loosen up with more use, requiring you to reset (lean) the mixtures over time.
Ed Cregger
I didn't realise that
---------------------
I'm not trying to insult your intelligence and I have no way of knowing how much experience you have. Pardon me if I stepped on your toes. You didn't answer as though you understood what I was saying. That is why I persisted, waiting for an acknowledgement.
The vast majority of "engine problems" that I see with newbies (less than 10 years flying experience) and their engines is that most grossly underestimate how long it actually takes for an engine to be broken-in enough to arrive at its peak performance. Until you get the engine to that point, it is still in the break-in process and cannot be expected to handle well.
Too much nitro is the next major culprit for two-stroke flyers and inverted engine installations are number three. Although the order of these problems is arguably debatable.
Ever notice that the engines that do break-in quickly never quite seem to arrive at said performance peak? Break'um-in, break'um-out. <G>
Ed Cregger
Free advice is worth exactly what you paid for it - including mine.