Lucas Di Pentima

Hi Nev! Yes, I know that Pennzoil TC is the best, but here in Argentina is not being sold (the entire Pennzoil brand doesn't exist here) so I'm trying to get some other good oil that's available here. You or Maj told me that the Castrol 2T red was a good one too, on other posts I read that the Castrol is the Activ 2T, and searching here I have found the Castrol Actevo X-Tra 2T, this one is semi synthetic instead of mineral as the Castrol Activ 2T, could it be OK too? It complies JASO FD, API TC and ISO EGD standards. Yesterday I sent this question to Rotax via the website http://www.rotax-aircraft-engines.com/ contact form, I'm still waiting for an answer. Best regards

Thanks Nev, I asked because this oil also comply with the API-TC spec, that is (as far as I know) for air cooled engines. Searching on the web i've found not many but some forum posts about the usage of this oil for ultralights and got some positive experiences, but nevertheless I wanted your opinion. Here are some of my findings: http://www.rotaryforum.com/forum/archive/index.php/t-21802.html http://www.ul104.eaachapter.org/rotaxrickengineinfo.htm

Hello all, I've been told by an experienced ultralight pilot that he's using the Texaco Havoline TC-W3 2T oil, suitable for water and air cooled engines (it passes the API-TC standard also), I've searched the forum and cannot find any reference about this oil, do you have some kind of info about it? Here in Argentina is being imported from the USA. Best regards

Hi Nev! When you say that the engine runs cooler with a high ethanol quantity, do you refer to the water temp, the EGT or CHT? I can measure the first two, and those are a bit low, what should I do to correct it?

Hey Gerry, thanks for the video! Actually, I've started my quest of knowledge about the 2 stroke engines by watching this video! And because I found it so useful, I bought their book about ultralight, but sadly there's not much more info about engines on it :( Best regards

Hey Frank, thanks for the welcome! Sorry I didn't answer earlier.

Hey Phil! thanks for all the posts, sorry I'm replying just now, that's because usually I'm away from the computer at weekends. First, let me tell you that I got the typo, 20-something degrees C for the engine would be just too cold. :) I'm having between 55 to 65 degrees C, I think that I should be getting at least 70 don't you think? Many on my airclub put some kind of paper of plastic to partially block the radiator. I think this is an awful solution and would like to know why I should be doing it if I don't live in a cold weather region. The oil I've been using is ESSO Aquaglide outboard oil, because almost all pilots on my airclub use it (including the flying school). As I've said, many decisions I make are because someone with more exprience in the field has told me. This Aquaglide oil has been discontinued and now they have changed to some nationally produced oil that I'm not aware of its features, and I have a bottle or 2 of Aquaglide left. I've been adviced on another thread to change to Castrol 2T red bottle, and luckily it seems to be available on my country. About the plugs gapping: The 532 manual says that it should be 0.50mm (0.02 in), is that the maximum or the ideal value? About RPMs: Until recently I've installed a faulty RPM gauge (it readings were higher than the true values), so I installed a new one and my only tests for the moment were on the ground: I got 6400rpm on full throttle. The manual says that the maximum recommended is 6800rpm (the same as the 582, am I right?) and I suppose that this kind of revs are to be used on full throttle on take offs only, is that a mistake? Why the 532 don't warn about not using the engine above 6350 RPM? As far as I know, the prop pitch should be set testing the full throttle RPM: I have to get close to (but no more than) 6800rpm on the air, so maybe on the ground I should aim for 6600rpm at full throttle. This could explain why I'm getting low EGTs on cruise (no more than 1000F on one cylinder, and 950F on the other): I've read that if the prop has too much pitch, it will impose in the engine a higher load and this higher load produce lower EGTs (and higher CHTs, but those I cannot measure because I don't have the instrument), is this incorrect? About the prop balance: I haven't detected vibrations but I'll take your advice if I change its pitch as both blades are indepent of each other. About the plugs and carb setting: I'm getting somewhat black plugs but the carbs have the correct jets and needle as the manual describe, maybe the blackness on them are because I wasn't pre-gapping (newbie mistake, nobody told me and I didn't look at the manual... OUCH!) them until now? About ethanol on fuel: In Argentina there's a law that says that the gas suppliers must add at least 5% of alcohol. I've checked this on the Argentinian's Shell website and there it says that their gas have between 5% and 10% of ethanol. I'm aware of the effects of ethanol on plastic fuel lines and tanks, my ultralight has a steel tank so I'm safe on that side. Well, the message got a bit lengthy, thanks for you time and help :) Best regards, Lucas.

Nev, Maj... thanks for so much useful tips, I'm learning here more than in few years I've been in this great world of ultralight! I've searched on the web and it seems that the Castrol 2TT red can be obtained (many things from abroad here in Argentina are hard to get since our nice government closed pretty much all imports), I'll get myself a box of 12 bottles and hope to burn them off quickly :)

Hey Phil, I'm not the original owner of this engine, so I don't know how well it has been treated. Plus, I'm a newbie in this area and trying to learn as fast as I can for obvious reasons :) My problem is that every 6 to 8 hours I've had some kind of power drop on the engine, and almost every time it has been solved by changing the plugs (I've had other problems, ie: carb spilling fuel that I solved by buying new jet needles, jets, etc). I know that spark plugs shouldn't be changed so often, so I'm searching why this happens. I've changed the double EGT gauge, the EGT probes and the RPM gauge so I can diagnose with some degree of accuracy what is happening. The data I'm seeing these days are the following: * EGTs: 950F & 1000F (in different cylinders, at cruise) - At low throttle (4500 - 5000 rpm) on final approach, the EGT goes up a bit (approx a 50F rise) * Water temp: 131F to 140F (55C-60C) * Spark plugs (NGK B8ES) color: very dark brown, almost black. No carbon deposits and not oily. * Sometimes hard to start The point ignition has been installed as new about 5 flight hours ago. The things I have to check/test are: * Spark plug gapping: I've always installed them as they came in the box. I have to check if they're gapped as per the manual recommendations. Also, when I bought this plane the plugs that came with it were the NGK B8EV (platinum electrode, as I understand), but as I can't find those plugs on my city and the Rotax manual say that they should be the B8ES, I thought that this is not the problem. * Using higher octane gas: I've always used 95 RON gas, but I've read that pre-mixing it causes an octane drop. * Covering part of the radiator to get higher water temps, I think the ideal should be around 158F (70C). * Test if the RPM at full thottle get to 6800 as I used to have an old and uncalibrated RPM gauge until recently. Maybe the problem is with the prop pitch, if at full throttle the engine doesn't get to 6800 RPM, I should reduce the propeller's pitch. (and therefore, the engine load, that produces a drop in EGTs)

Hi Maj! I didn't know the NGK required re-gapping for 2 strokes, nobody on my airclub told me, thanks! I'm using pre-mix (2%) Esso's Aquaglide Oil for 2-stroke marine engines, it's the one all the people here use (the same one that our flight school uses without any issues with an Rotax 503) with 95 Octane (RON) gas. Maybe I should try with the high octane (98 RON) gas, as I've read that pre-mixing gas decreases the octane value from the very beggining. Best regards, Lucas (please can you tell me how to change my name on the forum? I didn't found the option in the account preferences! hehe...)

Yes, the 532 are single plug per cylinder :( I think the problem are the plugs being fouled, but what I can't still detect is the reason for the fouling, so I thought the low EGTs were some kind of hint. The HKS 700E is used a lot in Chile with Flightstar ultralights, here in Argentina the Rotax is the standard, but I wanted a 4-stroke (912s are too much for an ultralight as far as I know) for enhanced reliability. As for the gapping, the manual states that 0.5 mm (19.68 thou?) is the correct one, on some websites I read that the gapping should be between 0.40 - 0.50 mm, you say a little more is better? I didn't checked the gapping on plugs, always installed as is... I'll check them as soon as I go to the hangar. Have a nice labour day! (it's an international holiday, isn't it?)

Hi Nev! I will check those temps in my next test and come back to you. I did notice an increase on EG temps when reducing throttle when in final approach to landing, don't remember how much, maybe 50F or so.

Thanks Maj and Nev for all the great info. Luckily this 532 has its hours counted, as I have a HKS700E waiting to take its place in a near future. Nevertheless, I want to make sure all is running correctly on the 532 before I sell it. All these doubts appear because every approx 6 hours I have had some kind of failure that was corrected by changing the plugs. (I use NGK B8ES, as described in the manual). Reading the plugs as you say, I can see they are (very) dark brown, almost black... but they don't show any carbon deposits. I have available a video from the last time I had a partial failure, I'm attaching the video so you can see it. Check at 0:50, the left camera captured the engine's sound. Another reason that could produce low EGTs is too much load on the engine (prop over pitched, as I learnt from Brian Carpenter's lecture from Rainbow Aviation). I've recently bought a new RPM gauge so I can check if this is the case, I haven't tested yet, but on full throttle I should get 6800 RPM, right? I did tested it on the ground and I got 6400. All this tinkering as Maj says is because of the continuous problems that I've been having. My original idea was to be a simple ultralight pilot (aka: ultralight user) but now I know that I should learn about all this, to properly take good care of my engine. :) I've been receiving help from people here but the problems persist. Thanks for all the help!

Thanks for the tips Maj, I forgot to say that the carb needles are on its lower setting, I cannot get the fuel-air mixture any more leaner, and that's why I'm worried. The needles, and jets are all new and the right ones as the parts manual describes (I have had a hard time trying to get the 532 manuals but fortunately the nice folks from rotax-owner.com helped). My fellow pilots from my airclub say that it's preferable that the engine run on the hot side of the allowed range, what are your thoughts about this?

The EGT gauge and probes are new, I have purchased myself some months ago. The water probe and gauge came with the ultralight (which I bought about 4 years ago).