Top End on Big Bore Continental (TSIO 550)

[ziggysanchez]

21 hours ago, L. Trotter said:

I realize there is scattered info on this topic but would like to update / consolidate  the topic and receive some advice.

I have a (new to me) 2007 Acclaim (1100 hrs TT) no prior engine work. Now burning 1 Qt every 1.5 hrs. Cylinder pressures low 60's throughout. Some leak heard in the breather line on nearly all cylinders. Valves look good on Bore Scope. Engine runs smooth, starts easily. Plane sat for extended periods prior to purchase. I'm told I need a complete top end.

Here is an article from Mike Busch https://www.savvyaviation.com/wp-content/uploads/articles_eaa/EAA_2014-06_cylinder-work-be-afraid.pdf which is not very flattering in regards to top overhauls. In essence, catastrophic engine failures are more likely to occur after "proper maintenance practices"! The more cylinders replaced the higher the probability-so "Be Afraid". It seems the large bore turbo Continentals typically only make it to mid-time (about 1000 hrs). OK, I'm afraid! where do I go from here? It seems top end overhauls are routine but is this the right answer? Here is a loaded question.....What have you done when faced with this dilemma? Why?

Complete Top Overhaul ? If so, with what...OEM, Superior Air Parts (Millennium), Engine Components Inc. (ECI), Aircraft Cylinders of America, or recondition my own cylinders.  Where?

Pull the engine and have complete rebuild or factory Remanufactured?

 

 

I had the non turbo version of this engine in my Cirrus and started to burn a quart of oil every 1.5 hrs after the engine had reached approx 1800hrs TTSN. The diagnosis was "stuck" oil control rings. Some guys were doing what they called a "ring flush" to try to see if they could remove the carbon that was causing them to stick with mixed results. I was about to do the soak on the cylinders in my engine to see if it had any effect on oil consumption before pulling the cylinders but due to unexpected circumstances ended up not needing to. I had heard it worked for some and not for others. To me it seems like it's worth looking into before tearing into the engine. 

[kmyfm20s]

I would find an excellent shop like Lycon to overhaul your existing cylinders. They can flow balance and match the pistons and make sure the valve are properly seated much better than new cylinders. You could also ask them about porting them. I had them do it when I overhauled the top end of my J. It was impressive, the engine will run very smooth!

I think any reputable shop can replace an entire top end, they do it all the time. I would discuss your concern that Busch talks about in his articles with them before hand so they know. In an ideal world they would replace 3 cylinders at a time but that's time consuming. Just my thoughts.

[Nathan Peterson]

Hi L. Trotter,

I complied with the following SB on my TN and was very happy with the results.  The reduction in oil consumption was dramatic.  I flew a three leg trip

KFYE-KWWD-KCWA-KFYE all above FL180 - FL240 and started out with 7.5 qts. and at the end of the trip I had  6 qts.   I was very happy after I installed the SB.... I was 

consuming at about 1qt. per 2 hours of operation.  My compression's  were all in the high 60 to mid 70's.  

I hope this info helps you.

 

Also recommendations on Shops.   Premier Aircraft, Ft. Lauderdale.   KFXE.  Ray Bysiewicz.  First Class Shop.

 

M20-319.pdf

[Hondo]

kmyfm20s mentioned Lycon.  Barrett is also excellent.

http://www.bpaengines.com/services/

For precision, they use Serdi valve seat cutting machines.
http://www.serdimachines.com/index.php/us/

For an expert opinion, give Monty Barrett a call, 918-835-1754.