BillLipson Posted January 20 Posted January 20 Looking for recommendations for for where I can obtain a reasonably priced leak down tester in Australia. Must have the recommended 1mm orifice.
skippydiesel Posted January 20 Posted January 20 (edited) You can buy a cheap one online and convert it to the Rotax 1mm orifice, using a dab of epoxy, drilled out with a 1 mm bit - simples! Related point: Both the cylinder leak down test and the compression test (I advocate both) are relative ie your first test(s) when the engine new (ish) will provide a "baseline" for future testing. With the exception of very worn/damaged engines, one off testing has little diagnostic benefit - bit like suddenly deciding to have the crankcase oil test. Edited January 20 by skippydiesel 1
pluessy Posted January 20 Posted January 20 Use a common automotive compression tester (dynamic). Leak-down tests might have been the "standard" in the industry for 100 years but the dynamic compression test is more accurate (less low end results) and should be used as the primary test. Leak-down is useful to determine the location of the leak, but then you don't need the tester set-up, just the spark plug adaptor (old spark plug), solder a hose barb fitting on, add a short section of hose and an air line fitting (male). Then plug it in to your air supply through a pressure regulator. The Toledo (and ToolPro) brands doesn't specify the orifice size. They are more than likely around the 1mm mark. If you need it, I can see if I can measure mine. They are available from Supercheap & Repco, most likely also from Bursons etc. 392419.pdf 1
pluessy Posted January 20 Posted January 20 Just checked my automotive leak down tester (similar to the Toledo/ToolPro), it has a 1.5mm drilling in the body. To make it relevant to the aviation test, I would need to drill that out and put in a 1mm bush/jet. Also read this: https://www.aopa.org/news-and-media/all-news/2023/july/pilot/savvy-maintenance-unbelievable-compression
skippydiesel Posted January 20 Posted January 20 I would need to drill that out and put in a 1mm bush/jet. EPOXY!
Thruster88 Posted January 20 Posted January 20 The length of the orifice is also important. The differential pressure tester is designed to check the compression of aircraft engines by measuring the leakage through the cylinders caused by worn or damaged components. (1) For an engine cylinder having less than a 5.00-inch bore; 0.040-inch orifice diameter; . 250 inch long; and a 60-degree approach angle.
Admin Posted January 21 Posted January 21 Is the one in Clear Prop no good for what you need? Engine Cylinder Leakage Tester WWW.CLEARPROP.COM.AU Heavy duty cylinder leak-down testerWorking pressure 0-100PSIMeasures leakage as percentage 0%-100%Suits all local and...
BillLipson Posted January 21 Author Posted January 21 Thanks to all for your responses. Very much appreciated.
pluessy Posted January 21 Posted January 21 same as the one I have. Remove the regulator, drill out the hole, make a suitable orifice (0.040" dia x 1/4" long) and insert to meet the FAA spec. The existing 1.5mm hole will give you good results, though🙂
Admin Posted January 22 Posted January 22 Clear Prop also has another version and currently in stock which is cheaper as well: Engine Cylinder Leakage Tester WWW.CLEARPROP.COM.AU Heavy duty cylinder leak-down tester Features This automotive compression tester works with most car models and gasoline engines...
Blueadventures Posted January 22 Posted January 22 (edited) On 20/1/2024 at 12:42 PM, BillLipson said: Looking for recommendations for for where I can obtain a reasonably priced leak down tester in Australia. Must have the recommended 1mm orifice. Look at the features on the E2A-1000 at Aircraft spruce, I have that one and made a 1/2” by about 300 mm pipe rather than the flexible hose connection into the spark plug thread in head. Works a treat. I recommend the need for the valve after the gauge for available pressure so you can turn on to get slight flow of air to confirm at TDC on compression stroke. Then open for full pressure adjusted for 80 psi or maybe 87 your choice. Such worth the extra bit of money. Edited January 22 by Blueadventures
pluessy Posted January 22 Posted January 22 1 hour ago, Admin said: Clear Prop also has another version and currently in stock which is cheaper as well: Engine Cylinder Leakage Tester WWW.CLEARPROP.COM.AU Heavy duty cylinder leak-down tester Features This automotive compression tester works with most car models and gasoline engines... This is the compression tester, not leak-down 1
Admin Posted January 22 Posted January 22 3 minutes ago, pluessy said: This is the compression tester, not leak-down Sorry, thanks @pluessy I forgot the question was about Leak Down. Just trying to promote the Clear Prop Shop as it is Clear Prop that makes this site available free for everyone 3
skippydiesel Posted January 23 Posted January 23 On 21/01/2024 at 12:41 PM, pluessy said: same as the one I have. Remove the regulator, drill out the hole, make a suitable orifice (0.040" dia x 1/4" long) and insert to meet the FAA spec. The existing 1.5mm hole will give you good results, though🙂 As I keep saying EPOXY - just use some HD epoxy, to plug the existing hole and then carefully drill with a 1mm bit - there is no need to drill out/enlarge what you have and then fit a plug with a 1mm hole. This aperture is for relativly low pressure air, without abrasive characteristics and as an amature, infrequent use, tool does not warrant the effort of redoing it in metal. If achieving the same result in metal makes you happy - go for it! FAA - Australian??? Inches - Australian??? I agree with leaving the tester as is - as mentioned earlier - the leak down test is primarily a comparative one ie record an initial reading, then compare all future reading with this, noting changes.
facthunter Posted January 23 Posted January 23 If you pressurise a cylinder on TDC make sure it doesn't move from TDC or the prop will whack someone.. ???? Another delayed post Skip, flow rate is what you are trying to get and diameter length of the hole and it's finish all play a part in that . Nev
Blueadventures Posted January 23 Posted January 23 (edited) 25 minutes ago, facthunter said: If you pressurise a cylinder on TDC make sure it doesn't move from TDC or the prop will whack someone.. ???? Another delayed post Skip, flow rate is what you are trying to get and diameter length of the hole and it's finish all play a part in that . Nev Agree, must be right on TDC otherwise will drive piston down and direction will be relative to before or after TDC. I have passed on info to Bill. Edited January 23 by Blueadventures 1
pluessy Posted January 23 Posted January 23 1 hour ago, skippydiesel said: As I keep saying EPOXY - just use some HD epoxy, to plug the existing hole and then carefully drill with a 1mm bit - there is no need to drill out/enlarge what you have and then fit a plug with a 1mm hole. This aperture is for relativly low pressure air, without abrasive characteristics and as an amature, infrequent use, tool does not warrant the effort of redoing it in metal. If achieving the same result in metal makes you happy - go for it! FAA - Australian??? Inches - Australian??? I agree with leaving the tester as is - as mentioned earlier - the leak down test is primarily a comparative one ie record an initial reading, then compare all future reading with this, noting changes. IF you want to make one that meets the FAA spec (AC43.13 1B), then you need to make the orifice to spec and insert it. Filling the hole with epoxy and drilling 1mm will give you something close, but not as per spec (the OP requested 1mm orifice, so I take that as "FAA spec"). Because the FAA did give that spec, it is the standard in the aviation engine industry. The 2 major engine manufacturers (and Rotax) refer to that: 2
skippydiesel Posted January 23 Posted January 23 (edited) Pluessy - Its a compartaive test. If you have precision/certified testing equipment, you may get the same/similar results from diffrent certified testers. If you use the same tester (povo pack or most expensive) the results should be consistent ie you don't actually need to go the the trouble of modifying a povo tester to (near) certified standards - the same tester will deliver consistent results or at least close enough for the average home mechanic. If you want to convert by drilling out & inserting a purpose made plug that's fine however the cheapest quickest way, is to use high quality epoxy to achieve the near regulation( ID 1 mm x 3mm long) aperture. The next best would be to form or join a club that will purchase & share expensive infrequently used equipment. I would compare the use of this type of tester (Cylinder Leak Down & Compression) to getting a crankcase oil analysis/test. The first one you do, is just to establish the base data , almost useless in its own right. Subsequent testing (if you consistently test at the same number of service hours and same/very similar oil, similar/same fuel, can then be compared with the base data. The comparison will tell you (trained operator) if the engine is performing/wearing as expected - the more tests the better the quality of information, from which to make your deductions. FYI: I know the LDT can also be used as a diagnostic tool for damaged valves & rings, etc, however its main benefit is tracking, over time, the changes in cylinder integrity. Edited January 23 by skippydiesel
pluessy Posted January 23 Posted January 23 If you make your own tester eg the cheapy or a modifed version, then the OEM specs are meaningless! As already pointed out, the leak-down test is overrated. Do a dynamic compression test and track that. Quicker, simpler and more accurate representation of the internal condition. 1
facthunter Posted January 23 Posted January 23 If you know what you are looking for, you can do a pretty good check pulling it through by hand and you can do that easily before the first flight of the day. How much the engine Breathes out the breather is important also and you can hear the valves leaking if you listen in the exhaust or intake with the throttle fixed wide open. If your engine shakes or has a different beat. Investigate that. IF it "fixes itself" it's still suspect because they usually don't. Nev. 1
skippydiesel Posted January 23 Posted January 23 3 hours ago, pluessy said: If you make your own tester eg the cheapy or a modifed version, then the OEM specs are meaningless! As already pointed out, the leak-down test is overrated. Do a dynamic compression test and track that. Quicker, simpler and more accurate representation of the internal condition. Why not do both, while you have plugs out and keep a record for later comparison.
Kev Posted January 23 Posted January 23 On 20/1/2024 at 12:42 PM, BillLipson said: Looking for recommendations for for where I can obtain a reasonably priced leak down tester in Australia. Must have the recommended 1mm orifice. Sorry Bill, I sold mine on here just recently. Regards Kev
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