Highest time TSIO 360 LB

[Ragsf15e]

13 minutes ago, Z W said:

To stir the pot, my engine doesn't run smooth LOP, so these are all ROP hours. 

I do keep the CHTs under 380 at all times, easy to do with adjusting the cowl flaps. 120KIAS full power climbs to cruise altitude. Always have kept TIT under 1625, but lately I keep it a little lower, under 1600, at the price of .3-.5 GPH. Usually cruise 70-75% power. No idea if this contributed to the engine's successful run or if I've just been lucky. Your mileage may vary.

If you’ve updated all the accessories as well as you say, looking for a field OH from a good shop in advance of being forced into overhauling is probably a good idea.  One of the benefits of factory reman is getting all the accessories oh as part of that, but if you’re happy with yours, a shop could just focus on the engine and probably be “cheaper” than factory.  Cheaper is in air quotes though….

[hubcap]

On 1/27/2026 at 8:01 PM, LANCECASPER said:

Early TSIO-360 engines had their problems, but it seems like the longevity improved over the years.

https://www.dropbox.com/scl/fi/kzbk4z7sit4hsobopsy5u/Early-Continental-TSIO-360-problems.pdf?rlkey=fegnjhavujq7uio0go76nad2m&dl=0

To your point, the original TSIO-360's only had one temperature probe for CHT and the POH was quite frankly too aggressive for the engines to handle. I have talked with a lot of guys who own this engine, and with a modern engine monitor and engine management, I think its very reasonable to expect the full 1800 hours TBO. I believe @jlunseth went ~2,300 hours on his 231 before doing the overhaul. 

I manage my engine very conservatively, never letting CHT's get above 370 even in the climb and in cruise the CHT's are typically 350 or less running LOP. It has a little over 900 hours on it and still has good compressions. I had the rotocoils replaced during the last annual. 

[Fly Boomer]

2 hours ago, hubcap said:

I had the rotocoils replaced during the last annual. 

Any recollection of the price of the rotocoils?

[Crawfish]

 

2 hours ago, Fly Boomer said:

Any recollection of the price of the rotocoils?

Last time I bought rotocoils it was fairly inexpensive if I’m remembering correctly in the range of 35$. 

Edited January 30 by Crawfish
rotocoils Auto corrected to protocols

[Patrick Horan]

On 1/28/2026 at 2:06 PM, LANCECASPER said:

I mentioned infant mortality in my post and for sure it could happen on any new or overhauled engine. On most engines I agree with you on over-TBO engines having proven reliability, but not the TSIO360, if you personally haven't flown all of those hours from new.

I've had a couple of them and if you fly them very conservatively (CHT 380 or lower) you stand a better than not chance of hitting TBO with a set of cylinders half way.  But early on Mooney and others marketed these as speed demons and put in the POH very high temperatures as being acceptable. The redline on the factory CHT was 460!!! On a hot day with the cowl flaps closed and not-so-good baffles you had a hard time keeping it in the low 400's. At least I did when I first bought my 231, until going to my first MAPA convention and sitting in on a the K model forum. High temps didn't turn out so well for most owners, as described in the post i made yesterday with the Dropbox link to the history of the TSIO-360 engine. On this engine, the more times the airplane has changed hands the greater the chances are that it has been flown incorrectly by a new owner. 

@Z W has flown this one correctly and that's why he has been able to run it to 2800. But  personally at 2800 hours TT I would feel more comfortable changing out the engine with a factory engine and feel that my chances would be better with the new engine.  Others may feel differently. We all make our own choices.

One of the reasons I traded my '83 231 for a Bravo in 1996 is that mine was getting very close to TBO and it was using more oil than I was comfortable with and once I ran the numbers on a new engine, even back then, plus all of the improvements on the M20M it helped me justify trading for a new airplane. (You need a lot of justification to do that, and I'm pretty good at convincing myself . . lol).  Ironically the next owner of the 231 converted it to a 262, just like @Z W's airplane, which, thirty years later now belongs to @geoffb on here.  My 1996 Bravo now belongs to @Patrick Horan on here. . .   the list goes on . . lol.

Im still enjoying 9153Z! Still trying to get the cylinder heads colder. But I am putting in a Gi275 and getting rid of the vacuum system 

[hubcap]

On 1/29/2026 at 6:03 PM, Fly Boomer said:

Any recollection of the price of the rotocoils?

It is not an expensive proposition. I would guess it’s less than $1 AMU but I don’t recall the exact price. In my opinion it is a very minimal expense to deal with the angled valves on the Continental engines. There is a special tool required in order to take the pressure off the valve spring while you change the rotocoil. I think the tool is available from Aircraft Spruce for $100 or so.