pudestcon Posted April 10, 2012 Posted April 10, 2012 OK, some issues here I'm hoping you can help me solve I have a brand new Rotax 582 on my T500 Thruster, the engine has just turned over 25 hours on the clock. It is driving a 68" 3 blade Brolga prop with 12 degree pitch blocks through a "B" reduction box at 2.58. Now this engine has always tended to overheat from run-in on. I have a hard time keeping the temps below 80 degrees indicated on a brand new VDO gauge connected to a brand new sensor in the engine head, all connected together with the wiring that came with the unit. So, unless the new gauge is faulty, I think the temp gauge is reading correct. I will, however, double check this next time I'm at the airfield by sitting the sensor in a pot of water and heat it up. I'll cross reference the temp gauge reading with a thermometer. I have only just pulled the prop[ apart to check the pitch, and I must say I was surprised to see such a fine pitch. I was expecting something near the high side of the range, around 16 degrees. I thought the overheating would be caused by too coarse a pitch setting and I could reduce the over temp reading by reducing the pitch - but not so. Another complication for you to digest; I have never been able to get full (6800) revs from the 582, either on the ground or when flying around. Most I've got is 6200RPM, so again I thought this would be due to a coarse pitch setting. Now I have to rethink. The EGT readings are identical at about 1100 on the gauge when at 6000RPM, so I reckon the carbies are right. I checked the barrel slides in the carbies and they are opening right up at full throttle. So I have 2 issues - an overheating engine, and an engine that is not achieving full revs. Where do I go from here learned forumites? Pud
Keith Page Posted April 10, 2012 Posted April 10, 2012 Pud... I know it may sound simple we must start at the basics :- "Have you changed the radiators out too, the blue heads need a larger radiator than the grey heads". there is my .25 cents worth. Keith Page.
terryc Posted April 10, 2012 Posted April 10, 2012 OK, some issues here I'm hoping you can help me solveI have a brand new Rotax 582 on my T500 Thruster, the engine has just turned over 25 hours on the clock. It is driving a 68" 3 blade Brolga prop with 12 degree pitch blocks through a "B" reduction box at 2.58. Now this engine has always tended to overheat from run-in on. I have a hard time keeping the temps below 80 degrees indicated on a brand new VDO gauge connected to a brand new sensor in the engine head, all connected together with the wiring that came with the unit. So, unless the new gauge is faulty, I think the temp gauge is reading correct. I will, however, double check this next time I'm at the airfield by sitting the sensor in a pot of water and heat it up. I'll cross reference the temp gauge reading with a thermometer. I have only just pulled the prop[ apart to check the pitch, and I must say I was surprised to see such a fine pitch. I was expecting something near the high side of the range, around 16 degrees. I thought the overheating would be caused by too coarse a pitch setting and I could reduce the over temp reading by reducing the pitch - but not so. Another complication for you to digest; I have never been able to get full (6800) revs from the 582, either on the ground or when flying around. Most I've got is 6200RPM, so again I thought this would be due to a coarse pitch setting. Now I have to rethink. The EGT readings are identical at about 1100 on the gauge when at 6000RPM, so I reckon the carbies are right. I checked the barrel slides in the carbies and they are opening right up at full throttle. So I have 2 issues - an overheating engine, and an engine that is not achieving full revs. Where do I go from here learned forumites? Pud Hi Pud, with your 582 and gear box if you are getting 6200 revs flat out you do have 16 degree pitch blocks. If you want [and you should] to get 6800 revs you need to replace them with 15 degree pitch blocks. the maths don't lie. Altitude does make some different but not a lot unless you are on a high mountain top. If your pitch blocks have a 12 on them it must be for something else and not relating to pitch. Regards Terry
pudestcon Posted April 10, 2012 Author Posted April 10, 2012 Pud...I know it may sound simple we must start at the basics :- "Have you changed the radiators out too, the blue heads need a larger radiator than the grey heads". there is my .25 cents worth. Keith Page. The radiators have not been changed, didn't know about the bigger size radiators so I better do some research on it. Thanks, and I reckon your ".25 cents worth" could very well be worth a whole lot more to me. Pud
pudestcon Posted April 10, 2012 Author Posted April 10, 2012 Hi Pud, with your 582 and gear box if you are getting 6200 revs flat out you do have 16 degree pitch blocks. If you want [and you should] to get 6800 revs you need to replace them with 15 degree pitch blocks. the maths don't lie. Altitude does make some different but not a lot unless you are on a high mountain top. If your pitch blocks have a 12 on them it must be for something else and not relating to pitch.Regards Terry G'day Terry, Well the numbers on the pitch blocks are certainly where the pitch numbers are supposed to be found on the Brolga props - look like they have been either cast in or punched in with a letter punch set. I'll check it under a magnifying glass when I get home. So if the pitch is 12 degrees the engine should be achieving 6800rpm no problems, yes? Wonder if I need to check the tacho now.... 2nd guessing again, I seem to be good at that!! I think I'll get hold of a tacho that reads prop revolutions and see what that shows. Let me see... engine revs/reduction box gearing= prop revs. 6800/2.58= 2635.66 revs at the prop. Is this correct? Our airfield is at 1330' asl according to my Recreational Flying 5" GPS. Pud
Barefootpilot Posted April 10, 2012 Posted April 10, 2012 My old 582 on a Thruster had the high stack radiators and in the warm qld temps would still reach up toward the high side on thr ground or low level but once in the cruise it would settle down. Remeber airspeed cools things down a lot quicker than reducing power so its better to level off low and cool it off and then keep climbing to you higher cruise height. Thats my 25 cents worth so now you have 50 cents!
Riley Posted April 10, 2012 Posted April 10, 2012 Pud, if you loan me that 50 cents on low interest long term repayment, I'll loan you a set of bona fide 13* and/or a set of 17* pitch blocks to play with if you wanna do some trials. cheers
terryc Posted April 10, 2012 Posted April 10, 2012 G'day Terry,Well the numbers on the pitch blocks are certainly where the pitch numbers are supposed to be found on the Brolga props - look like they have been either cast in or punched in with a letter punch set. I'll check it under a magnifying glass when I get home. So if the pitch is 12 degrees the engine should be achieving 6800rpm no problems, yes? Wonder if I need to check the tacho now.... 2nd guessing again, I seem to be good at that!! I think I'll get hold of a tacho that reads prop revolutions and see what that shows. Let me see... engine revs/reduction box gearing= prop revs. 6800/2.58= 2635.66 revs at the prop. Is this correct? Our airfield is at 1330' asl according to my Recreational Flying 5" GPS. Pud Hi Pud, The 17 degree blocks offered by riley will make the problem worse by loading your engine even more. I have used them on mine but found them no good with two up so took them off straight away. The 16 degree blocks I used mostly [150 hours ] and what was on it when it came from the factory gave me 6200 revs exactly at full power on climb out the same as yours. When my engine was rebuilt after my accident the l2 that did it insisted that I change the 16s to 15s because the power lost in that extra 600 revs was considerable and needed with a t500. He was dead on the new climb out revs were exactly 6800 revs and a better climb rate. I've used 17 16 and 15 degree blocks and there's no doubt the 15s are the correct ones for the 582 on a t500 I remember tony hayes writing an article on this, maybe on this forum. I'll see if I can find it for you. Terry
Tex Posted April 10, 2012 Posted April 10, 2012 Pud try a 'Tiny Tach' they are very accurate. I pitched my Drifter to 6500RPM on climb out for best all round setting... climb rate and cruise YMMV
pudestcon Posted April 10, 2012 Author Posted April 10, 2012 G'day Terry,Well the numbers on the pitch blocks are certainly where the pitch numbers are supposed to be found on the Brolga props - look like they have been either cast in or punched in with a letter punch set. I'll check it under a magnifying glass when I get home. So if the pitch is 12 degrees the engine should be achieving 6800rpm no problems, yes? Wonder if I need to check the tacho now.... 2nd guessing again, I seem to be good at that!! I think I'll get hold of a tacho that reads prop revolutions and see what that shows. Let me see... engine revs/reduction box gearing= prop revs. 6800/2.58= 2635.66 revs at the prop. Is this correct? Our airfield is at 1330' asl according to my Recreational Flying 5" GPS. Pud Well here's a photo of the pitch blocks showing a 'cast in' number where the Ultra-Props documentation says to look for the pitch degree identification. It looks like 12 degree pitch blocks to me. Now with 2 up and a full load of fuel I reckon my Thruster climbs out very well - nothing spectacular mind, but not bad all the same. The tacho reads 6100 - 6200 max revs, and does not sound like it is screaming it's t#ts off. A mate of mine has a digital rev counter gauge that reads a reflective tape stuck on a prop blade. I'm going to see if I can borrow it this weekend to check the revs. Just a thought - is there another way to check the degrees on a pitch block - is it simply a matter of reading the sloping face against the square edge to give you the angle? Pud
pudestcon Posted April 10, 2012 Author Posted April 10, 2012 I remember tony hayes writing an article on this, maybe on this forum. I'll see if I can find it for you.Terry Thanks Terry, I'd be interested in reading the article. Pud
pudestcon Posted April 10, 2012 Author Posted April 10, 2012 Pud, if you loan me that 50 cents on low interest long term repayment, I'll loan you a set of bona fide 13* and/or a set of 17* pitch blocks to play with if you wanna do some trials. cheers I know what you are like with legal tender of this country Riley, I'll never see that 'borrowed' coin again:laugh: Looking forward to catching up sometime soon to chew the fat and try some of your Godawful coffee you keep in your hangar - might even take a look at those pitch blocks as well thanks! Pud 1
pudestcon Posted April 10, 2012 Author Posted April 10, 2012 The radiators have not been changed, didn't know about the bigger size radiators so I better do some research on it. Thanks, and I reckon your ".25 cents worth" could very well be worth a whole lot more to me.Pud Jeez those higher radiators don't come cheap eh? Anyone got a good s/h set they are prepared to let go? Pud
pudestcon Posted April 10, 2012 Author Posted April 10, 2012 Pud try a 'Tiny Tach' they are very accurate. I pitched my Drifter to 6500RPM on climb out for best all round setting... climb rate and cruise YMMV Thanks Tex, I'll try my mates rev counter first and see how I go with that. Is it true that Tiny Tachs are not available anymore? Pud
pudestcon Posted April 10, 2012 Author Posted April 10, 2012 My old 582 on a Thruster had the high stack radiators and in the warm qld temps would still reach up toward the high side on thr ground or low level but once in the cruise it would settle down. Remeber airspeed cools things down a lot quicker than reducing power so its better to level off low and cool it off and then keep climbing to you higher cruise height. Thats my 25 cents worth so now you have 50 cents! That's what I'm doing all the time Barefootpilot, have done since the 582 was run in, but I need to do something about it before I inadvertently let the temp get above 80* one day when my attention is distracted. Pud
pudestcon Posted April 10, 2012 Author Posted April 10, 2012 Just a thought - is there another way to check the degrees on a pitch block - is it simply a matter of reading the sloping face against the square edge to give you the angle? If I've done this correctly then the pitch blocks are definitely 12* Do I need 11* pitch blocks or should I look for the problem elsewhere? Pud
Tex Posted April 10, 2012 Posted April 10, 2012 You can still get Tiny Tachs. Just thinking... high temp, low RPM on fine pitch ... if your tacho is cactus and is reading low (like 600rpm) it might explain all of them?
Methusala Posted April 10, 2012 Posted April 10, 2012 G'day Pud, I've just replaced my grey head with a blue head that I re-built. The grey head used to get 6,500 on climb out with a 68" Brolga set at 16 deg pitch. I'm using a Grand Rapids engine monitor instrument with limits set at the factory. The red warning light would flash if revs exceeded 6500. The new engine with identical jetting gives 6100 on climb out. I have re checked the timing but still no increase. I wonder whether it is a case of the new rings being tight and friction being the cause. I replaced the radiators with the new tall ones and have no temp problems but it does run up to 75 or 80 on climb. The plugs look ok with a light brown oil film. Egts are on the low side at 520-550 (650 is max). so I may get a size smaller main jet to try. I tried moving the needle circlip to lean the mid range but it went too high. If it doesn't change I may try 15 deg pitch blocks if they are available. I removed the oil pump and run 50:1 premix with Castrol Activ 2t. Don't know whether this is helpful but my 2 bobs worth. Cheers,Don
pudestcon Posted April 11, 2012 Author Posted April 11, 2012 G'day Pud, I've just replaced my grey head with a blue head that I re-built. The grey head used to get 6,500 on climb out with a 68" Brolga set at 16 deg pitch. I'm using a Grand Rapids engine monitor instrument with limits set at the factory. The red warning light would flash if revs exceeded 6500. The new engine with identical jetting gives 6100 on climb out. I have re checked the timing but still no increase. I wonder whether it is a case of the new rings being tight and friction being the cause. I replaced the radiators with the new tall ones and have no temp problems but it does run up to 75 or 80 on climb. The plugs look ok with a light brown oil film. Egts are on the low side at 520-550 (650 is max). so I may get a size smaller main jet to try. I tried moving the needle circlip to lean the mid range but it went too high. If it doesn't change I may try 15 deg pitch blocks if they are available. I removed the oil pump and run 50:1 premix with Castrol Activ 2t. Don't know whether this is helpful but my 2 bobs worth. Cheers,Don I may well have to replace the radiators as you did Don - we'll see. What ratio is your reduction box, are you using a different ratio box on the new blue head, or the same? Pud
Riley Posted April 11, 2012 Posted April 11, 2012 OK Pud I'll up the ante. Make it a $2.00 long term loan and I'll throw a R582 tall radiator hookup into the deal! Seriously, if you find you have to go down that road in attempts to resolve the issue, I have a set of twin tall radiators on the Suzi 3 cyl experimental project (presently stalled) that I'd be happy to LOAN you for trial purposes to prove the possibility before shelling out for a replacement cooling system. And, while I can bear the pain & hurt from that unkind comment on my coffee, my dear old Mom used to tell me that coffee & smokes would stunt my growth so you better come around for more cuppas because, as I recall, your radial growth could do with some stunting. Give us a call if & when when you need. Cheers Riley
pudestcon Posted April 11, 2012 Author Posted April 11, 2012 OK Pud I'll up the ante. Make it a $2.00 long term loan and I'll throw a R582 tall radiator hookup into the deal! Seriously, if you find you have to go down that road in attempts to resolve the issue, I have a set of twin tall radiators on the Suzi 3 cyl experimental project (presently stalled) that I'd be happy to LOAN you for trial purposes to prove the possibility before shelling out for a replacement cooling system. And, while I can bear the pain & hurt from that unkind comment on my coffee, my dear old Mom used to tell me that coffee & smokes would stunt my growth so you better come around for more cuppas because, as I recall, your radial growth could do with some stunting. Give us a call if & when when you need. Cheers Riley Ahhh Riley, you have cut me to the core!! But I like your offer of the radiator loan to check if the problem goes away. I'll see what transpires over the weekend and be in touch next week sometime. Cheers, Pud
Methusala Posted April 11, 2012 Posted April 11, 2012 Pud, reduction is 2.58:1 - no change to anything except the donk. I think it may be to do with friction between bores and rings. Like to know whether Maj Millard or Facthunter have any thoughts on this? BTW, fascinating that your prop is set at 12deg! Cheers, Don
terryc Posted April 11, 2012 Posted April 11, 2012 Well here's a photo of the pitch blocks showing a 'cast in' number where the Ultra-Props documentation says to look for the pitch degree identification. It looks like 12 degree pitch blocks to me.[ATTACH=full]17098[/ATTACH] Now with 2 up and a full load of fuel I reckon my Thruster climbs out very well - nothing spectacular mind, but not bad all the same. The tacho reads 6100 - 6200 max revs, and does not sound like it is screaming it's t#ts off. A mate of mine has a digital rev counter gauge that reads a reflective tape stuck on a prop blade. I'm going to see if I can borrow it this weekend to check the revs. Just a thought - is there another way to check the degrees on a pitch block - is it simply a matter of reading the sloping face against the square edge to give you the angle? Pud Hi Pud, yes their 12 degrees all right. 1/So we know the pitch for certain 2/ We know the 582 for certain 3/ Gear box. Do we know for certain the gearbox, I don't think we do. Maybe you could double check this Pud. Gees this is fun :roflmao:Sorry Pud I know it's not for you
facthunter Posted April 11, 2012 Posted April 11, 2012 Bigger radiators are worth a try for the temp problem. Why are the revs down so much? Is there any damage to the prop leading edges? A rich mixture can do this to some extent, but don't go leaning it out , unlesss you do it very carefully, and have determined that it IS rich. Are the air cleaners blocked? Nev
Keith Page Posted April 11, 2012 Posted April 11, 2012 Do the carbys belong this 582 and what is the fule mixture setting. I have a 582 in a Lightwing:- with the sparkplugs set at .5 of a mill and the exhaust leaks at the elbows sealed, on the climb out the EGT is cooler and the torque is noticeable i.e., less throttle needed, just a tad nothing great, but noticeable.
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