Conrad Posted December 7, 2016 Report Posted December 7, 2016 I've just received a new set of images of the inside of my plane. To anyone that knows what they are looking at, what does it look like to you? Specifically the choice I need to make is whether to just install a new thermostatic bypass valve (it's already ordered, pictured to the right of the old one) or if it would be wise to give some attention to the valve seat first. For reference this came apart because my plane is experiencing oil temperatures verifiably in the yellow and more than half way to the red, recorded on a day with OAT's around 65°F climbing at 2500 rpms, 130mph, almost full rich. The old valve looks to me like it has significant wear, which is surprising given that it was installed in 2012 and has flown less than 200 hours. It looks to me like the seat has multiple visible contours near the bottom of the attached image. Am I seeing that right? Seems bad. Quote
Guest Posted December 7, 2016 Report Posted December 7, 2016 The old valve is obsolete per Lycoming SB518D. Have you verified the oil temp system? Clarence Quote
Conrad Posted December 7, 2016 Author Report Posted December 7, 2016 4 minutes ago, M20Doc said: The old valve is obsolete per Lycoming SB518D. Have you verified the oil temp system? Clarence Huh, I knew about that SB, but I thought they looked like the same part. The oil temp system has been verified. There are two digital readings which agree and they've been checked against a calibrated thermometer. Quote
Conrad Posted December 8, 2016 Author Report Posted December 8, 2016 The problem is solved! It turns out it was the vernatherm, it was not opening nearly wide enough. The shop sent me a video of the difference between the old part and a new working on which is about to go into my plane, and it's pretty remarkable. I'll post it as soon as I have a more suitable connection to the interwebs. 3 Quote
carusoam Posted December 8, 2016 Report Posted December 8, 2016 Man, I'm to late to give my fuzzy PP opinion! How long has the first valve been installed? They have about a 40 year life span. Then when they give trouble they are too much cost to try and fix. You can now amortize the new one over the next forty years! Can you tell any difference with the aged one by operating the spring in your hands, or anything like that? Great pictures, thanks for sharing, Conrad! Best regards, -a- Quote
bonal Posted December 8, 2016 Report Posted December 8, 2016 Been dealing with a higher than ideal oil temp myself I installed a JPI temp gauge (another thread) and found a peak of 225 with a cruise around 205. I am going in for an oil change next week and hope I can see your post of the operation of your vernatherm as I'm thinking this may be the source of my problem and would love to have a reference for comparison. Would not be surprised if mine is original equipment and as such 52 years old. One thought on oil temps and condensation since we all know it's not good to ground run an engine to keep it exercised because we end up with moisture since the oil does not reach a high enough temp to (cook) the water out. If an engine operating in flight never reaches a high enough oil temp to cook out the water wouldn't that be a possible concern for corrosion in the engine. For example if you never even get above 200df is that hot enough to cook out the water content. Quote
Conrad Posted December 8, 2016 Author Report Posted December 8, 2016 (edited) Here you go. The video is of a 200 degree bath. Edited December 8, 2016 by Conrad 3 Quote
Conrad Posted December 8, 2016 Author Report Posted December 8, 2016 @bonalI would be surprised if your Vernatherm is 52 years old because they are mandatory for replacement at overhaul and have been for quite some time. Quote
bonal Posted December 8, 2016 Report Posted December 8, 2016 Good to know I will be looking into my logs to see if done. Unable to view video on my iPad and since I'm off from work won't have access to a real computer perhaps someone with skill can convert to an acceptable format Quote
Conrad Posted December 8, 2016 Author Report Posted December 8, 2016 @bonal I just put it on youtube and embedded it in place of the earlier MOV link. I think you should be able to see that! 2 Quote
bonal Posted December 8, 2016 Report Posted December 8, 2016 Perfect and quite a difference between the two. Thanks for doing that. Mooney space is so cool 1 Quote
bonal Posted December 15, 2016 Report Posted December 15, 2016 Was able to get in for my oil change today and took my trusty Svea 123 and made a nice vernatherm soup. Cold was .100 opened to .285 when soup was ready. So operation is correct will look into flushing oil cooler in the spring. Nice spotless screen is always nice to see. Had to taxi in the rain back to hangar and took almost as long to wipe off the rain as did to Change the oil. Quote
carusoam Posted December 15, 2016 Report Posted December 15, 2016 Great video, Conrad! Best regards, -a- Quote
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