MarkD34M Posted June 3, 2020 Report Posted June 3, 2020 Fellow Mooney Drivers: I have a situation that is perplexing me and hoping you may be able to provide some guidance or suggestions. The oil temp is running a bit warm on the JPI 730 - probe is on the alternate location up near the prop on the front of the case. The oil temp is running a bit warm in the 210-215 range up there but when I adjust the prop forward, the oil temp increases immediately to redline or close (230ish) and when the prop gov is turned down, the oil temp comes down and stabilizes. Also, if I climb the oil temp goes up quickly - I believe this has to do with the prop governor doing it's job keeping the rpm's constant. If I lower the nose, the oil temp decreases quickly. Since the probe is right up by the prop governor, does anybody have any theories. Data points below. Also, for those of you who have the JPI or similar, can you please provide the difference in oil temperature you see between the JPI and the original equipment gauge? (probes are at different ends of the engine). - Just had prop and governor overhauled - Engine freshly overhauled at Poplar Grove - 3 hours flying - oil pressure stable at 50 psi on the ships gauge - Original Oil temp ship's gauge is not reading correctly (known issue, new one being searched for) - JPI 730 Oil Temp probe located in the alternate location up front by prop gov and showing in the 208-225 range. Many Thanks! Quote
bfreelove Posted June 3, 2020 Report Posted June 3, 2020 I don't think this would have anything to do with the prop governor directly as oil isn't really circulating through the prop, the governor is just allowing more or less oil in the piston depending on what blade angle is needed to keep the RPM constant. That location will definitely read higher than the original location as it's reading oil temperature before the oil cooler, and the standard location reads it after the oil cooler. In general the peak oil temperature in the system is typically 40 degrees higher than what you read on the gauge (oil temp after the cooler). If that was the only change I wouldn't worry about it until you get the original probe fixed. The temp going up with increased RPM is normal, as is in the climb. It's probably more sensitive if looking at the temp before the oil cooler. If it comes back down in cruise then it's controlled and okay. Quote
MIm20c Posted June 3, 2020 Report Posted June 3, 2020 What was the reason for the overhaul? Did you have an oil starvation issue or making metal issue that might have contaminated the oil cooler? Quote
carusoam Posted June 3, 2020 Report Posted June 3, 2020 There are a couple of places an OilT probe can be placed in a aircraft engine...some locations are better than others... Find out where the ship’s gauge is... and see if the engine has a mirrored location for a second instrument... a nearby one would be almost as good... Ask whoever installed the JPI probe, why they selected that spot... Grab some pics... ships gauge and JPI gauge location.... Grab an engine manual... or POH might have it too... look for oil access locations... Expect that the OilT varies in different locations of the engine... putting a probe anywhere will get a sub-optimal result... PP thoughts only, not a mechanic... Best regards, -a- Quote
kortopates Posted June 3, 2020 Report Posted June 3, 2020 that is a real problem because the 730 is not a replacement for your primary oil temp and technically your primary is required for flight. The front part of the engine is where oil gets the hottest - at the end of it journey from the rear to the front. Still what you describe doesn't sound normal. If it's real, then oil pressure has to be dropping with the increasing oil temp, otherwise it's an indication issue.Nobody wants to spend lots of $ on old OEM guages - perhaps instead it makes more sense to instead install a modern TSO'd engine monitor like the 900. Lots of benefits for the cost and it adds resale value to your R.Sent from my iPhone using Tapatalk 2 1 Quote
carusoam Posted June 3, 2020 Report Posted June 3, 2020 Oil Temp Gauges for Ovations are a sourcing problem... .4amu and a four month wait... (Lasar memory) Did the temp gauge fail Slowly by going cold over time? (Dead sensor Thermistor issue) PP thoughts only, Best regards, -a- Quote
MarkD34M Posted June 3, 2020 Author Report Posted June 3, 2020 Thank you for the feedback: - the Oil Temp OEM is reading low and has since I got the plane - been using the JPI. Mooney Service Center trying to locate one (it only comes up to touch the green on occasion) - the JPI is in the galley up near the very front of the engine by the prop - engine was overhauled because the crank gear and the alternator coupling had issues so they IRAN'd it and flushed the oil cooler during the process - kortopates, the 730 was installed very recently, perhaps if I can't find the OEM transducer I might have to re-upgrade - video attached. please look at how quickly the temps change both up and down with climb or descent (same happens when I move the prop RPM) - If any of you have the JPI can you share the temp difference you may be seeing between the two? JPI Video.MOV Quote
PMcClure Posted June 3, 2020 Report Posted June 3, 2020 I have a set of oem gauges for sale. If interested pm me. Quote
Cruiser Posted June 3, 2020 Report Posted June 3, 2020 I have a JPI 830 connected to the front port on the pilot side of the case. It reads about 10°F higher than the OEM. It is stable and the response is the same as the panel gauge. It reads 170 - 180 during normal operation. Long climbs to 8 or 9k altitude during the summer heat and the oil will get to 205°F but quickly comes down to 180 in level flight. Something is wrong. 1 1 Quote
MIm20c Posted June 3, 2020 Report Posted June 3, 2020 8 hours ago, MarkD34M said: - engine was overhauled because the crank gear and the alternator coupling had issues so they IRAN'd it and flushed the oil cooler during the process JPI Video.MOV 3.11 MB · 1 download We had the same issue with the alternator coupling. Please know that the rubber bits can plug up the oil suction screen and starve the pump of oil (necessitating new parts because of the scoring). 50 psi is a little low in our experience with the io-550. I feel for you, it was a very expensive process for us...I might end up swapping a new alternator and coupling every 1250 hrs to save myself 30k down the road. Quote
carusoam Posted June 3, 2020 Report Posted June 3, 2020 Focus on the sensor and it’s location... It isn’t the display... Since the Ship’s oilT has gone on vacation, you can put your JPI’s sensor there to see what your OilT actually is... It may be possible that the JPI 730 can be used for primary instruments... (check with JPI if OilT is qualified for primary using the 730) The JPI 900 is nice for this... because it has many variables that are qualified as primary... The 700 series... some are some are not... (maybe)... Its not like you are doing something wrong by putting the JPI sensor in the place of the ship’s sensor... (That ship sailed already) The moment, the ship’s sensor failed... that is when the AW question arose... Since replacing the ship’s oilT sensor is the big challenge... pick up a primary gauge from JPI, EI, or other... Or source an OilT sensor from another Mooney... the OilT sensor is shared with other Mooneys built in the early 90s... Often an MSer installing a JPI900 is removing the old instruments... (worked for me) PP thoughts only, not a mechanic... PP thoughts only, -a- Quote
MarkD34M Posted June 4, 2020 Author Report Posted June 4, 2020 Mlm20c: We were concerned about that and Poplar did a full tear down to confirm. I'll keep an eye on the oil pressure but my indications prior to teardown were in the 50-55 range. Anthony, much appreciated and good suggestions as always. My understanding was the probes were different? If I hadn't just put in the 730, I'd make the 930 investment. Perhaps down the road.... if I can source a OEM probe and solve the mystery and get duplication of readings that would be my short term preference. As an aside, I am also running W100 Mineral Oil and the engine has been completely overhauled so my thoughts are: - as the break-in continues, temps may come down a bit - switching to Phillips 20/50 might improve things nominally - I just want to make sure the engine is getting adequate oil and breaking in properly (the oil temp fluctuations in the "alt probe location" have me wondering if the oil flow there is appropriate. #overthinking Thanks again for the comments / suggestions. Quote
LANCECASPER Posted June 4, 2020 Report Posted June 4, 2020 On 6/3/2020 at 8:49 PM, MarkD34M said: Mlm20c: We were concerned about that and Poplar did a full tear down to confirm. I'll keep an eye on the oil pressure but my indications prior to teardown were in the 50-55 range. Anthony, much appreciated and good suggestions as always. My understanding was the probes were different? If I hadn't just put in the 730, I'd make the 930 investment. Perhaps down the road.... if I can source a OEM probe and solve the mystery and get duplication of readings that would be my short term preference. As an aside, I am also running W100 Mineral Oil and the engine has been completely overhauled so my thoughts are: - as the break-in continues, temps may come down a bit - switching to Phillips 20/50 might improve things nominally - I just want to make sure the engine is getting adequate oil and breaking in properly (the oil temp fluctuations in the "alt probe location" have me wondering if the oil flow there is appropriate. #overthinking Thanks again for the comments / suggestions. You're definitely not overthinking it. In fact according to your POH you are underthinking it, since you are still flying the airplane. A working ship's oil temperature gauge is required even for daytime VFR flight in your Ovation. Having a JPI 730 does not supersede that, it is only supplemental information. 2 Quote
MarkD34M Posted June 4, 2020 Author Report Posted June 4, 2020 Lance - fair point. I have not had the plane long and it was tied up for 5 months for the overhaul. Each flight we have tried to troubleshoot the factory gauge and with some success (although still not where it needs to be) - connections one flight - ground another - rewire, instrument, etc. Now we are searching for a new one. Appreciate the view. Thanks, Quote
StevenL757 Posted June 5, 2020 Report Posted June 5, 2020 On 6/3/2020 at 9:49 PM, MarkD34M said: We were concerned about that and Poplar did a full tear down to confirm. I'll keep an eye on the oil pressure but my indications prior to teardown were in the 50-55 range. This is normal for the IO550G On 6/3/2020 at 9:49 PM, MarkD34M said: As an aside, I am also running W100 Mineral Oil and the engine has been completely overhauled so my thoughts are: - as the break-in continues, temps may come down a bit - switching to Phillips 20/50 might improve things nominally - I just want to make sure the engine is getting adequate oil and breaking in properly (the oil temp fluctuations in the "alt probe location" have me wondering if the oil flow there is appropriate. #overthinking Thanks again for the comments / suggestions. First, your temps WILL come down a bit...particularly your CHTs. You'll also notice your oil temps drop a bit back into normal territory. Second (not turning this into a "this oil is better than that" discussion), I'd switch to Aeroshell 15W50 rather than the Phillips 20W50. Better corrosion protection overall. Ultimately, you'd be better-off using the Exxon Elite, but it's no longer available...unfortunately. Lastly, DO NOT skimp or shortcut the break-in procedures. Follow the instructions to the letter, or you'll have problems for the rest of the engine's life. Ask me how I know. Steve Quote
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