582 0verheating issue

[pudestcon]

G,day Pud.Here are a couple of photos of my radiator setup, the push pull handle on the left of the dash is for the radiator flap.

With your tracking problem, I was told in my early days when flying a skycraft scout that if your prop was out of track you could put a shim of some sort behind the blade that was back, seeing as you only have one blade out of track you should be able to put a shim behind it to push it forward.

 

My engine only rev,s to 6000 WOT has done ever since ive owned it, I thought that was the norm until I was told I should be getting about 6500 to 6700. I have 15% pitch block and my carbies are good, Ive never worried about it, it gets of reasonabley quick, climbs out ok, cruises at 50 kts indicated at 5400.

 

SAJ

Can't see any photos SAJ:private eyes:. Interesting about the shims - what shim material would you use? Anyone else have a view on using a shim to change a propeller blade tracking? Initially I wasn't worried about the engine revs either, but now I know about it and the water temp is hot I thought I'd find the cause as both issues could be related. Just a thought, but it may be that your setup with the extra radiator capacity is masking the real reason for overheating. In my situation with the blue head engine, where it needs the extra capacity (around 163.5 cm2 of extra radiator surface area over the grey head engine) your third radiator idea should solve the problem, giving an excess of 76.3 cm2 surface area capacity.

Food for thought....

 

Pud

 

 

[pudestcon]

Pud I hit post reply befor I had put the photos in, having down trouble down sizing photos, when I work it out I will send them to you.SAJ

It's easy if you use Microsoft Picture Manager (MPM) SAJ. When you have a photo on screen in MPM click on "Edit Pictures..." in the menu bar across the top of the screen, a box will appear down right side that gives you the option to resize the photo. You need the 640x480 size to have it accepted for upload to the site here. At least, that's how I do it:wink:

Pud

 

 

[turboplanner]

Could no extra revs also be attributed to no extra capacity (fuel) from the carburettors - I'm thinking main jets too small or blocked, in effect, governing the engine? I'll keep your idea in mind Nev. Thanks.Pud

That's the reason I suggested looking at the stamped numbers on the main jets, and making sure they match the standard specifications.

 

This isn't racing where you might be prepared to play around with jet sizes in return for a much shorter engine life, so I wouldn't start going away from the standard jet size, because it should produce the expected rpm. As I've mentioned you've invested thousands of dollars in a new engine, and it only takes the slightest experiment off standard to burn out a piston and have to start all over again.

 

 

[robinsm]

I was chasing revs in a grey head engine and changed the main jet sizes. Burnt a hole in one of the pistons 300 ft about the airstrip on take off. Be very, very carefull when changing away from the recommended jets!!!!!!!

 

 

[facthunter]

As to your question ,Pud, on the Fuel supply alone being the situation. NO.... If that was the case it would have been all over for your engine a while ago. You would have had a lean mixture at high power. A no go area with two-strokes.

 

A piston engine is an air pump (amongst other things). If the load is too high, like too tall a top gear in a car, it will not rev enough to suck in enough air (and fuel as a mix) to use the last bit of throttle, and to develop it's rated power.. Nev

 

 

[turboplanner]

I'm with Facthunter and Wayne on this - the byproduct of the load being too high in a two stroke is an immediate increase in heat.

 

If the engine was revving out to its rated limit freely and the water was overheating, then I'd say it was heat exchanger.

 

However, the issue to me points back to the prop, and while I have no experience on prop setup at all, it seems to me that one blade tracking out of true could be causing turbulance or deflection.

 

 

[pudestcon]

As to your question ,Pud, on the Fuel supply alone being the situation. NO.... If that was the case it would have been all over for your engine a while ago. You would have had a lean mixture at high power. A no go area with two-strokes.A piston engine is an air pump (amongst other things). If the load is too high, like too tall a top gear in a car, it will not rev enough to suck in enough air (and fuel as a mix) to use the last bit of throttle, and to develop it's rated power.. Nev

So if the main jets are the correct ones and the throttle slide is opening fully, then you are suggesting I look to the propeller as the source of not achieving maximum revs, yes?

Pud

 

 

[Methusala]

I am still baffled by the facts as they appear in both my case and in Pud's. We both have replaced an existing 582 of considerable hrs with a new (in my case re-newed with new seals, needle rollers, de-glazed barrels and rings) engine of the same basic specs. When equipped with carbs jetted identically, exhaust system identical as well as gearbox and prop, we get more heat (coolant temp) and less power (rpm). I have suggested perhaps it is simply the increased friction between the new rings and the cylinder wall. Yesterday I saw 6200 in cruise for the first time since running in some 4hrs ago. I saw a similar effect from my Aeropower conversion years ago. Exchanging radiators for the larger units can do no harm but the rest may settle down as the engine gathers hours. As long as CHT's and EGT's are within limits (I have a Grand Rapids engine information monitor with twin cht and egt's as well as coolant and tach) little harm should be done. Don

 

 

[facthunter]

Rings bed in pretty quick. The amount of energy that you are talking about is considerable, and I doubt that the rings could account for it. Certainly changing radiators can do no harm and is also a priority idea. Has there been a change in some of the specs for these engines. Timing, porting, compression ratio exhaust back pressure etc Is the lower octane fuel correct these days for the engines.? Nev

 

 

[Methusala]

G'day Nev, As I say, I am mystified by the outcome. I have checked the timing, plugs mags and so forth. The setting up of the rotary valve is so straight forward as to be (almost) fool proof. The fuel is fresh and 91 ron as specified. When Pud started this thread I thought that surely the answer must rapidly evolve. I believe that the assembly of my engine was carried out carefully and correctly. However something is missing and hopefully in time it will become known. I am grateful for all contributions to this theme. I also thought that the rings should be well bedded after following the Rotax procedure. Just clutching at straws perhaps. Don

 

 

[facthunter]

There WILL be an answer. Do the radiators anyhow. Accept nothing that hasn't been proven in a situation like this. I feel a bit bad because I encouraged Pud to go via the new engine route. It's usually just a matter of bolting it in and break it in and go. Nev

 

 

[Methusala]

Thanks for your reply Nev. As you say, "never stop learning". I'm sure that Pud has no regrets in following your advice. Don

 

 

[SAJ]

Sorry pud - have resized the pictures - hopefully they will load now

 

SAJ

 

 

 

 

 

 

 

[propfarmer]

Hi Pud,

 

have been watching this thread with interest and after seeing the above photos and reading that the alignment of one blade is different to the others, have had a thought...

 

Is it possible that the 12 deg blocks can be put on incorrectly and are oriented the wrong way giving a false pitch? eg. the block designed to be infront of the blade is infact behind it and vice versa.

 

Could this be the reason for one blade being out of alignment? One is correct and two are wrong or two correct, one wrong?

 

ps. have no experience with maintenance on this type of engine or prop so what i am questioning may not be possible?

 

Good luck.

 

 

[pudestcon]

There WILL be an answer. Do the radiators anyhow. Accept nothing that hasn't been proven in a situation like this. I feel a bit bad because I encouraged Pud to go via the new engine route. It's usually just a matter of bolting it in and break it in and go. Nev

Hehehe, I can't believe you are feeling "a bit bad" Nev... You should be feeling a bloody "lot bad"

Seriously though, as Don has said, I definitely have no regrets about getting the new engine, and fully expect to work these issues out in due course, and have many many hours of flying fun. So thanks for your input Nev, it has been very valuable, and thanks for your concern as well.

 

Pud

 

 

[pudestcon]

Sorry pud - have resized the pictures - hopefully they will load nowSAJ

Thanks SAJ. Good to see you worked out how to load photos - it's not too hard once you get the gist of it.

Your solution to the overheating problem is certainly novel, and obviously working. I like the idea of shutting off the lower radiator when its not needed - I hope it is attached well!!

 

Cheers, Pud

 

 

[pudestcon]

Hi Pud,have been watching this thread with interest and after seeing the above photos and reading that the alignment of one blade is different to the others, have had a thought...

 

Is it possible that the 12 deg blocks can be put on incorrectly and are oriented the wrong way giving a false pitch? eg. the block designed to be infront of the blade is infact behind it and vice versa.

 

Could this be the reason for one blade being out of alignment? One is correct and two are wrong or two correct, one wrong?

 

ps. have no experience with maintenance on this type of engine or prop so what i am questioning may not be possible?

 

Good luck.

G'day propfarmer, the pitch blocks are fully interchangeable front and back. If you check out photos number 1 and 4 in SAJ's post #88 you will see what I mean. SAJ's propeller set up is identical to mine. The pitch blocks in use are the ones featured here http://www.competitionaircraft.com/ultralight-aircraft-parts.html

Some information on prop combinations for the 582 can be found on this page http://www.competitionaircraft.com/Brolga.htm

 

Pud

 

 

[pudestcon]

For those that are interested, the assembly instructions for the propeller set up I have can be accessed from this page http://www.competitionaircraft.com/Brolga.htm then click on the link contained within the 1st paragraph under the heading "Assembly and Care of the Brolga Ultra-Prop"

 

Pud

 

 

[terryc]

For those that are interested, the assembly instructions for the propeller set up I have can be accessed from this page http://www.competitionaircraft.com/Brolga.htm then click on the link contained within the 1st paragraph under the heading "Assembly and Care of the Brolga Ultra-Prop"Pud

Hi Pud, remember that an ultra brolga prop is not the same as our brolga prop we use on our thrusters etc. The fellow that made our props got his hubs from ultra brolga props but that's all. The props we have are far superior and designed differently. If you had an ultra brolga prop then your 13 degrees pitch blocks would be correct, but you don't. What you have is a Australian made brolga which require 15 degree pitch blocks for a 582. If you borrow a another prop that tracks true with 15 degree pitch blocks I thinks both your revs problem and over heating problem will disappear.

Terry

 

 

[pudestcon]

Hi Pud, remember that an ultra brolga prop is not the same as our brolga prop we use on our thrusters etc. The fellow that made our props got his hubs from ultra brolga props but that's all. The props we have are far superior and designed differently. If you had an ultra brolga prop then your 13 degrees pitch blocks would be correct, but you don't. What you have is a Australian made brolga which require 15 degree pitch blocks for a 582. If you borrow a another prop that tracks true with 15 degree pitch blocks I thinks both your revs problem and over heating problem will disappear.Terry

Are you serious about two different Brolga props Terry?!! Bloody hell, this is never ending.

On saying that though, the status quo remains with my setup as I have the Australian prop blades teamed with the ultra hub, same as you are saying the Aussie Brolga had. That means I should have 15* pitch blocks when I have 12*. So the engine should be screaming it's lungs out - but it ain't!! Putting in 15* blocks will make the situation worse.

 

I posted the links above because the assembly and configuration of the propeller is identical to my setup.

 

Somehow, I think the RPM issue is not with the propeller because of the 12* pitch, rather it has something to do with fuel. I will be happy to be proven wrong on this, as long as it happens sooner rather than later. I believe the overheating is a separate issue caused by the smaller radiator assembly.

 

Pud

 

 

[Riley]

Tonight I’ve been trying to get my head around where I am with the under revving and overheating issues with my blue head 582. Here’s where I’m at and what I’ll be doing next time I’m at the airfield….Summary of known conditions in no particular order-

· Propeller. 12* pitch blocks on a 3 blade composite 68” Brolga prop, powered by a 582 blue head Rotax engine through a “B” reduction box 2.58:1 gearing. Propeller is second hand but in good condition. Number 1 blade weights 2 grams lighter than the other 2. Number one blade tracks 10mm to the rear of the other 2 blades at bottom centre of the propeller arc. No facility on this type of setup to adjust propeller blade tracking.

 

· Maximum revs 6200 WOT ever since brand new including during run in phase.

 

· Engine prone to overheating ever since new with temps wanting to climb through 80*c including during run in phase.

 

· The Bing 54 carburettor slides show synchronised and full movement through the entire throttle lever range. WOT position shows slide as wide open.

 

· Engine idles at 2000 RPM with vibrations felt until revs increased to 2200.

 

· Engine has 30 hours since new, as shown on electrically activated hour meter – true running hours possibly 27 or so.

 

· Tacho and water temp gauges are confirmed as reading accurate.

 

· Thermostat is confirmed as operating correctly.

 

· Enrichening circuits (choke) on the carburettors are functioning correctly with complete de-activation when levers returned to the ‘Off’ position. Engine starts with no trouble.

 

· All 4 spark plugs exhibit consistent tan/light brown colour, indicating correct fuel/air mixture.

 

· EGT gauges at 6000 RPM read 1100* identical on both cylinders.

 

· Engine runs on Caltex unleaded 91 Ron fuel at 50.1 mix with Castrol Active 2T 2-stroke oil.

 

· Air cleaners were brand new with the engine and are in as new condition.

 

· Carburettors were brand new with the engine and have not been altered in any way, or checked for synchronisation apart from visual inspection of slide operation on both carburettors.

 

· Exhaust system was brand new with the engine and has been slightly modified. Where the gases exhaust to outside air a 50mm long (or thereabouts) curved pipe has been added to direct the exhaust gases away from the wing skins. See photo in post # 52

 

· The 2 part radiators are the smaller version radiators from the old grey head 582 installation. New radiators were not purchased with the new blue head 582 engine.

 

Things to check when next at the hangar-

 

· Remove overflow bottle from the radiator coolant circuit to check if there is airflow interference from the bottle interrupting airflow around the radiators and engine. See photos.

 

· Fully inspect and check carburettors set up – All jets and needles, float levels, position of needle clip retainer in needle groove, position of white plastic retainer is above needle clip, pneumatic synchronisation of both carburettors, and full throttle slide movement (again).

 

· Fit larger test radiators on loan from Riley to ascertain benefit from larger radiator capacity.

 

· Check ignition pick up gap and timing of ignition.

 

Is there any other checks I should do at the same time?

 

Pud

G'day Pud

I'm probably 'preaching to the choir' but when you next get up to the hangar and commence your overheating 'rat-killing', ensure that you knock off each of your check points & test individually before moving on to the next if not successful. We all stand to learn from your saga so have fun old son but no short cuts!

 

 

[pudestcon]

G'day PudI'm probably 'preaching to the choir' but when you next get up to the hangar and commence your overheating 'rat-killing', ensure that you knock off each of your check points & test individually before moving on to the next if not successful. We all stand to learn from your saga so have fun old son but no short cuts!

Good advice Riley, and I fully intend to do just that. I want to know what effect, if any, each item will have.

I am having fun working through this with the help of you people here, and some others, namely Poll and The Runt who get in my ear constantly:blah blah:

 

Pud

 

 

[Guest Johnny B]

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 Ian,It's john from west swan.Finally managed to join up.Have been doing a bit of research re my thruster prop.Should be 6200 Max static rpm and flat out in straight and level flight 6500.From what I've read max red line should only be possible in a descent.So much info out there but this seems to tally with the old Victa.Max straight and level was 2550.2800 red line only possible in a dive.Fitted those doors yet?

 

 

[Guest Maj Millard]

Pud, If your only running 12 deg blocks and not getting the rpms, then it doesn't sound like the pitch blocks if everyone else is running 15 and doing ok. I think you do need the high radiators to keep your temps down, and the correct coolant. Are you using Castrol anti-freeze, anti-boil mixed 50/50 with demineralized water, as recommended by Rotax for that engine ?. The right coolant is a big thing on those engines.

 

Also remove the air cleaners from the carb, put the throttle at full and stick your finger in on the slide, see if you can push it up any further. If not adjust the brass nurled knob at the top to raise the slide all the way at full throttle. The needle needs to be fully up through the main jet for a full flow of fuel at full throttle. It is only the main jet that meters fuel at full throttle. Yes your Gbox/ engine rev calculations are correct. EGTs should run between about 1100-1250 deg farenheit, 1150-1225 is perfect. Don't go above 1250 if you can help it. Have you gapped your plugs correctly, they come out of the box new at 25 thou but run better at 22-24 thou....Coolant temp is what you watch on these engines and the range is 60-80 C. Mine always sat at 70 C with the thermostat fitted. Silly question..but I am assuming you do have 100mls of 90 wt oil in the gear box ?..as required.......................................................Maj...

 

 

[Tex]

EGTs should run between about 1100-1250 deg farenheit, 1150-1225 is perfect. Maj...

I thought 930-1150 is operating temp, 1150 1200 is caution range