1978 M20J turbo normalized - Low(er) oil pressure above 12k

[Shadrach]

1 hour ago, Fasterthanmycherokee said:

I was showing 191 TAS at 12,500

Really? So your TN’d J model is faster than an Ovation?

[Shadrach]

46 minutes ago, A64Pilot said:

I’ve had an injector clog several times in the 210, it never happened on takeoff, but if it did, I’d abort the TO or reduce power to min and land. It happened in flight, first time I fought to keep it rich enough, full rich and high boost, made the other 5 slobbering rich, after that I’d reduce power and let the lean one go wherever it wanted, power was low enough it didn’t hurt anything, it woud just lean out and pretty much die.

‘I got so I carried a 7/16” deep well socket and shorty wrench and a can of carburetor cleaner. Then one day it stopped clogging injectors and never did again, only did it three or so times.

Did you get a look at what clogged the injector?  I've never had a clogged injector but I likely won't given my mechanic and I are in agreement tat there is no need to check them if they are performing correctly per the engine monitor.  All of the injector issues I have had were mechanic induced.  One year at annual we discovered that all four injectors were cracked because someone over torqued the Bnuts.  After a particularly expensive repair station annual one year we found an injector so loose the line was only

[Fasterthanmycherokee]

20 hours ago, Shadrach said:

Really? So your TN’d J model is faster than an Ovation?

I wouldn't know the TAS of an ovation, but here ya go.

[DanM20C]

1 hour ago, Fasterthanmycherokee said:

I wouldn't know the TAS of an ovation, but here ya go.

Your TAS is in MPH, 191mph = 166kts.  Not as fast as an O. 

Cheers,

Dan

[A64Pilot]

7 hours ago, Shadrach said:

Did you get a look at what clogged the injector?  I've never had a clogged injector but I likely won't given my mechanic and I are in agreement tat there is no need to check them if they are performing correctly per the engine monitor.  All of the injector issues I have had were mechanic induced.  One year at annual we discovered that all four injectors were cracked because someone over torqued the Bnuts.  After a particularly expensive repair station annual one year we found an injector so loose the line was only

Little tiny bit of something black, most likely a deteriorating hose or maybe a fuel cell, Had a rubber look to it, that may sound silly, but I’ve seen several bits of black rubber in fuel strainers before that were coming from a bad hose, and it looked like that. It wasn’t a slowly clogging thing either, it was sudden.

‘But they mysteriously stopped one day and as far as I know nothing changed, but then I wasn’t doing the Annuals on that aircraft either.

Edited June 29, 2021 by A64Pilot

[Johnny R]

Just something to compare with

Did this flight the other day.

M20J Turbo Bullet

 

[bradp]

An aspect that has not entered the conversation is the condition of the magnetos, timing, spark intensity, spark duration, and shorting / jumping / alternate ground path conditions that can occur in high altitude and high temperature conditions.  The mags (esp low output like slicks commonly found on Js) are a weak part of the J engine setup, esp TNd. 
 

Re over square-.  You know every 300 hr wonderkinder CFI that told me to pull the throttle and RPM back never over square it.  I only lose 200 fpm and gain Fahrenheits by employing this (prob some combo of cylinder pressure duration at lower RPM and loss or cooling air). Lose lose in my mind.   I’m supposing the “lugging” descriptor is that bike in high gear starting out analogy. 
 

My J shows economy cruise at LOP.  25F.  I wonder if Mr Sandman literally made a typo and inserted ROP in lieu of ROP.  I haven’t read the full POH supplement but seems very in keeping with IO-360 management and I’m doubtful he Re-derived the performance data during certification testing.  Maybe he ignored the “when cruising at 75% power or less” since it’s a turbo at less than critical altitude? 
 

@Fasterthanmycherokee have you trialed WOT 25-50 LOP? You’d probably be giving up 5-6 KTAS but may gain additional fuel economy and lower temps / TIT. 
 

Can you share some of your uploaded flights on savvy with us? 
 

 

Internet J POH, but my POH is the same here. ^^^