It looks very interesting, more lubrication will probably not do any harm and many other components are lubricated using similar holes.. But I would be concerned about the modification of the camshaft. The oil pressure will be reduced in the bearing from where the oil is taken and the strength of the drilled camshaft must be assured. As usual the problem is that nobody in GA has the money to properly test engines. You would have to take a dozen, run them on the dyno until they break, modify the design and try again. I suppose the STC applies to N-reg only?
Seems if you’highlight’ and right click you can ‘go to’
You need to use the chain link button and enter the address like this: http://www.centri-lube.com/technologies.html
Is the camshaft hollow to allow oil to pass through it or do the holes act as a reservoir?
Is the camshaft hollow to allow oil to pass through it or do the holes act as a reservoir?
The ‘standard’ Lycoming camshaft is hollow and ‘open’ at either end (understand not so the Conti). You can see / blow through. Diameter is approx, 10-12 mm
Link these people drill holes (only small) in the camshaft bearing surfaces (there are three of these bearings – not sure they drill all). and strategical drill similar small holes in the cam lobes. They then put an expansion ‘seal’ plug in each end of the camshaft. Think these are mechanical expansion plugs that can be removed (cleaning out should a future ‘strip’ take place).
The drilling, particularly of the lobes, must be done with a rather special drill bit (say diamond / tungsten tipped) as it’s done retro to a complete hardened camshaft.
The revolving shaft plus centrifugal force does the rest.
I suppose the STC applies to N-reg only?
I have a copy of the EASA STC for this.
Seems this has been ‘certified’ since approx 2005 and was surprised that Adams Aviation, Surrry, England didn’t know. They are one of our main parts importers.
Firewall Forward (Centri-Lube) say (not a recent statement) that 1000 engines have been ‘done’.
I need to talk direct with Firewall Forwarding, but I’m still find it surprising that hardly anybody seems to be aware.
The oil pressure will be reduced in the bearing from where the oil is taken
In theory yes, in practice infinitesimal, as the surplus oil in the camshaft bearings will be ‘flowing’ out of the bearings in any case.
I find it an eloquent solution
The oil pressure will be reduced in the bearing from where the oil is taken
Have talked to Firewall Forward, Colorado, USA and they say the stock oil pump, as required for engine FAA certification, is capable of delivering 20 x the engines requirements.
and the strength of the drilled camshaft must be assured.
The drilled holes look no more than approx. 1.5mm dia. The stock camshaft would have to be on the point of failure for those holes to produce a critical situation.
I have just received a regular email from Savvy containing a link to the latest Mike Busch article on oil and thought it might be relevant to this thread:
[link fixed]
Lycoming Parts Stockist – suppliers, Europe ?
I asked back in the thread and just got one ‘contact’, which seemed to deal in ‘secondary’ stuff, not pistons, valves, cranks etc.
Maybe you leave it all to the engineer and he goes to the stockist.
Any good in-depth Lycoming parts stockist on the continent out there ?
Belgium, Germany, France etc..
In Germany at least those two sell Lycoming parts. Most other shops seem to buy their stuff there:
http://www.roeder-praezision.com
http://www.piper-germany.de/ersatzteile/
But you have to decide if you want to buy the parts yourself. If you call the price will be much higher than what they will quote your shop. So maybe it will be better to let the engineer buy the parts. According to German law that would make any warranty issues much easier if he sells you the parts and the labour on one invoice.
Some parts are sold in sets. So if you need many parts for a cylinder you might want to buy a complete cylinder set. The same goes for the camshaft and the tappets.
I hope you do not need a crank…?
I tried Roeder some months ago for something and they made it extremely clear they will not communicate in English.
I would ask Lycoming USA. They have a telephone number which is answered (eventually – might take half an hour).
FWIW:
At the last oil change of my TCM IO-550N I switched from 15W50 to W100+Camguard. According to most of the usual sources this combination will prevent rusting the best. I normally don’t believe in “homeopathy” but Camguard seems to be the one oild additive that makes a difference. Bought it at Aircraftspruce.eu, € 115 for four bottles. You need about 3/4 of one bottle for a 7 qts. oil change.
