cwalter

No issues with idle. The engine is full rich at idle. Full idle is very good with rise at cut-off. Idle at 1100 rpm I can dial back a good bit of mixture to get peak rpm. I get 7.8gph for my 1900rpm run-up(firewall mixture) which is what I always set to to get 24gph at T/O. So the issue is between run up and full power. Run up may be low enough power that the variance is not that noticeable. Thanks again.

Great input - thanks eveyone!

Thanks- I will call that out to the mechanic. The issue exists in cruise as well. I struggle to get 13gph best power flow in various cruise configurations firewall mixture. This happened even after the first mechanic set full rich to about 26gph full power. About 10,000 feet I begin to get some room to dial back mixture to 75 ROP. Given the fuel system was designed with a fixed waste gate I wondered if anyone has seen linearity issues like this due to a Merlyn install. Thanks for the input!

I (and mechanics) have all the manuals, STCs, service bulletins, etc. from Mooney, Continental, and STC holders to set up the system. I'm asking if anyone has seen problems with M20Ks that "by the book" set ups would result in unacceptable operating characteristics, specifically non linear fuel flows resulting in lean operations between low and high power settings. Non linear fuel flows resulting in normal operating parameters is not what I am referencing.

I have a 1979 M20k with intercooler and Merlyn Wategate. I recently had the fuel pump and mixture controller replaced/overhauled. I've had 2 shops, including a Mooney service center, attempt to set up the fuel system. I get full rich at idle, 24gph full rich at full power, but as I reduce manifold pressure my TIT/EGTs rise. I usually get about 18gph at 2600/30in TIT 1350 in climb and now get about 15-16gph with TIT approaching 1500. In cruise I have to use full mixture to get 75 ROP and at low altitudes it is more like 50 ROP. This M20K has always been set rich - firewall mixture was over rich on take-off (more than 24gph) and I had to set fuel flow in run-up so I would be at about 24gph on take-off roll. The current shops are setting to the book. Initially one would say it is one of the replaced components, but I'm thinking this may be an issue that had previously been compensated for by this over rich setting. Has anyone seen this type on non-linearity in the fuel system such that you get full rich at idle and take-off but run best power or less flows in between (all cases firewall mixture)? One of the mechanics suggested that the Merlyn may be driving a higher MP than the mechanical fuel control is "expecting" below full power. Any thoughts?

I have a 1978 231 M20K and need to replace the trim tube: I am reposting this note as i am still in need of this trim tube. This is second tube section from front and is P/N 915026-009 Thanks, Chris

I am reposting this note as i am still in need of this trim tube. This is second tube section from front and is P/N 915026-009 Thanks, Chris

Just confirmed it is second section. Do you want to call my cell at 404-409-8054 or email cwalter@marketsource.net to move forward? Chris

This appears to be the second section from front. The assembly looks to have 4 tube sections and this Part Number applies to section 2 (from front). My mechanic said it wore at about the back of the rear seats passing a former or bulkhead. I will verify with my mechanic. How is the condition of the tube? I really appreciate you responding! Chris

I have a 79 231 with a worn trim tube. Evidently the tube is installed losely in the airframe with some wear tape on it were it passes through and rubs on a rib. The rib has a wear gard on it as well. The tape on the tube wore through and it has worn about 1/4 into the tube wall. My mechanic is unable to find a replacement and Mooney has 3 people in the factory so any order could take a long time to fill at who knows what price. The part number is 915026-009. Is anyone aware of availability of this part or an alternative replacement of this part? Thanks, Chris

Awesome - Thank you. I assumed this from a mag wiring diagram but you never know if those images represent physical cylinder location and I had to assume which end was front/back. I questioned it based on plug rotation. 1/2 and 5/6 make the biggest move while 3/4 just swipe sides and T/B. Thanks Again!

Can someone help my identify the cylinder numbering for my 231 with TSIO-360? I've found firing order etc but no means to identify which cylinder is what number.

I'm not sure what the FAA issue could be. It is interesting that the company rep stated " there is only a 25 degree oil temp increase out of the turbo" out of the blue. I didn't ask about that at all in the conversation. The fact I found posts over 2 years old where Ed Kollin (last name?) stated FAA accceptance was only 2 months away and to this day they have not received acceptance raised a flag. The rep talked about the facts surrounding the aerobatic aircaft used in testing was a big deal but did not know if it was running a turbo was also interesting. Not sure any of this means a thing but before I added it I thought I would throw this out there.

I have noted the posted regarding Camguard but have a specific question related to turbos. Does anyone have experience with Camguard in turbo Mooneys? I have a '79 231 with about 450hrs SMOH and considering using Camguard with Phillips X/C. I've read a lot regarding Camguard but the concern I have is the fact they have not obtained FAA "acceptance" in turbos. I have seen posts at least 2-3 years old where Camguard representatives said turbo acceptance was a couple of months away. I spoke with Camguard and they claim it is political at this point but they made comment regarding turbo temperatures which leads me to believe there could be a concern there. They stated there is only a 25 degree increase in oil temp from input to output of the turbo but my mechanic commented that the oil is passsing bearings that are running hundreds of degrees. The system is designed to pass oil through quickly to limit the heat any given "parcel" of oil can pick up while still effectively cooling. Could there be a concern with Camguard and its reaction to contact with such high temp parts? Clearly it is operating in the high temp areas of combustion (cylinders and rings) without issue but I think turbo bearings are running at least double typical cylinder head temps. Thoughts or experience with Camguard and turbos? Thanks, Chris

You raise another good troubleshooting point. In my case you could not hold the switch - it was actually a short that was causing the trip. At least in the 231 the switch is also the breaker. It was enough of a voltage disruption to disrupted the auotpilot when engaged. That symptom still could have been the switch. In a 30 year old plane the contacts can get resistive!