The place for technical discussions about GA and flying.
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By Kemble Pitts
#1797767
Scenario
Bought an O-200 with 580 hours SMOH. Before fitting to the aircraft (Jodel) a top overhaul has been carried out.

Once installed we will need to 'break in' the engine. Conventional wisdom is to use straight oil for the break in period. Does anybody have an alternative view on that?

After the break in period we then have the option of using either a single grade ashless dispersant oil (W100 or W80) or a multigrade (say 15W50). I'd be interested in experiences of these options.
By riverrock
#1797771
https://www.lycoming.com/service-instruction-no-1014n

D. All other engines must be operated on non-dispersant mineral oil during the first 50 hours of operation, or
until oil consumption has stabilized. Use of LW-16702, while required for certain engine models as listed in
Part B above, could inhibit break-in on other engine models and therefore should not be used during break-in.
Reference Service Bulletin No. 446, Service Bulletin No. 471, and/or Service Instruction No. 1409 for
additional information. If an ashless dispersant oil is used in a new engine, or a newly overhauled engine, high
oil consumption might possibly be experienced. The additives in some of these ashless dispersant oils may
retard the break-in of the piston rings and cylinder walls. This condition can be avoided by the use of nondispersant mineral oil until oil consumption has stabilized and then change to ashless dispersant oil. Nondispersant mineral oil must also be used following the replacement of one or more cylinders until the oil
consumption has stabilized.
By riverrock
#1797778
We worked out that W80 Plus was pretty much the same price as W80 and buying LW-16702 separately. Not sure if you need it for you O-200 (I'm talking about an AEIO 360).
Multi-grade should be better than single grade, but the question is whether the expense is worth it.
User avatar
By Morten
#1797779
[Can of worms = open]
Worth reading: Mike Busch' review of oils and what to use when

My summary: Multigrade if you fly often but monograde if the engine sits for while between flights. (Ie most light GA) but swap to multi for the winter season. Potential benefits of synthetics mostly not applicable to GA piston engines, whereas mineral oil's better dirt capture again makes it more suitable for most GA use.
#1797794
Morten wrote:[Can of worms = open]


Quite. There's anecdotal evidence that engines fare a little better on single grade...though engines fare better being run regularly, and those which are run regularly are more likely to use single grade due to 1) cost, and 2) they're in an environment where you can reliably fly all year round and don't suffer from treacle-oil syndrome in the cold! So I don't think there's anything conclusive.

Then there's multigrade (with the additive) and the single grade (plus - with the additive) vs. non additive (non-plussed?). Lycomings are more prone to "sitting doing nothing" syndrome than Continentals in terms of the camshaft, so on the face of it (face of the camshaft?) would benefit more from the additive.

As to which sticks to the surfaces for longer. Dunno. Instinct would suggest that multigrade semi-synthetic runs off surfaces quicker, but that's not scientific!

I do know that when temperatures are very low, multigrade runs like treacle. I don't know what single grade does, it's probably even worse.

After all that, I have no recommendation, other than multigrade is probably better if the temperatures are low. But I don't know for certain.

:D
User avatar
By Kemble Pitts
#1797956
Thanks for the feedback guys. All of that seems to support my gut feel (and conventional wisdom).

Straight oil for breaking in, and then a W80/100 thereafter. Our aircraft is usually flown every week but can sit for weeks due to weather or soggy runway so the better corrosion protection of the mono-grades is the clincher.
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By CloudHound
#1805084
Just noticed Transair have a free delivery offer ending today Sunday 25th October and an 8% discount on Shell oil.

I've ordered a case of 6 x W80 Aeroshell at a cost of £7.71 per bottle. :thumleft:

(Continental O-200 35 hours a year)
#1805100
A spin on oil filter mod from Julian Mills is on the list.

I’m sticking to W80 coz of wot Paul says above.

I prefer Avgas from barrels or airport bowsers. Filling Jerry cans with 100lit of unleaded on our local forecourt isn’t possible unfortunately.
mick w liked this
#1805323
Paul_Sengupta wrote:As to which sticks to the surfaces for longer. Dunno. Instinct would suggest that multigrade semi-synthetic runs off surfaces quicker, but that's not scientific!


I should also have said that the multigrade has some sort of "cling" additive to stop it draining.

https://www.alphapioneer.com/doc/Piston%20Engine%20Oil/Aeroshell%20Oil%20W15-50/Aeroshell%20Oil%20W15-50%20Brochure.pdf

"The oil that stays on when your engine is off"
User avatar
By Trent772
#1805367
As time goes by and our ditch pump mine engines still haul us into the air, I think we need to keep up with lubricant technology.

Multigrades offer better flow at lower temperatures, while offering superior lubricity and protection at higher temperatures. Additionally, as previously mentioned, the multigrade oils stick better after shut down and during periods of inactivity.

20 years ago, we used W100 in the summer and W80 in the winter. Now, we just stick to 15/50 and enjoy year round protection.

Welcome to the 19th century :pirat:

Thinness or thickness of oil means nowt in terms of protection - it is the performance and constitution of the oil and its ability to perform at low and high temperatures that matter.
By riverrock
#1805370
Trent772 wrote:Additionally, as previously mentioned, the multigrade oils stick better after shut down and during periods of inactivity.

The single grade "plus" oils or the additive LW-16702 provide that "sticking" ability and as @Paul_Sengupta says there is some evidence that engines last longer on single grade oil.
Multi-grade has been associated with slightly lower oil temperatures (so make sure that your engine has run longer to get up to a temperature to burn off any water content), slightly better fuel efficiency (a few percent), slightly quicker movement around a cold engine (4 seconds rather than 10 seconds on a v. cold day), slightly reduced constant speed unit control...
its different - not necessarily better.
User avatar
By Kemble Pitts
#1806105
CloudHound wrote:Just noticed Transair have a free delivery offer ending today Sunday 25th October and an 8% discount on Shell oil.

I've ordered a case of 6 x W80 Aeroshell at a cost of £7.71 per bottle. :thumleft:

(Continental O-200 35 hours a year)


I buy my oil direct from Oaksey Park where the aeroplane lives, I'm pretty sure that none of the oils they sell (Total D100, D80, multigrade, straights - Total D = Aeroshell W) costs more than £6/litre