ORIGINAL:
I am a user of both a DA100 and DL100 engines - both in 2.6 Mtr planes. I'm not an extreme 3D pilot, but do like to have a ''bash'' every while and also dabble in a bit of IMAC. Both engines - for my purposes, have been extreamily reliable and problem free.
Recently though I have noticed 2 seperate incidences whereby the DL's have thrown a piston during, in what I would call, extreme 3D flying i.e - a LOT of throttle management, high revs and extreme transitions between idle and WOT.
Both occasions resulted in a complete ''engine seize'' and on both occasions the planes landed with relativly little damage.
I'm won't pretend or assume that DA have not had any failures, but would I be fair in now assuming that while both are extremily adequate for their purpose's, the DA's are more reliable (or less prone to failure) when it comes to extreme ''abuse'' during 3D flying.
I owned a DA 100 for two years and it was my primary IMAC plane for that entire period .
To say it had a lot of flights woul be an understatement , it was in the range of about 250 per year .
When the plane was sold on the engine went back to DA for full check up and re build if needed .
It was said they had never seen an engine sooo stuffed and still running . Now that engine had
a long run in period and after that it was flogged as hard as any could be . While it was said to
be stuffed the engine never stoped in flight and is was a power house right until it was sold on .
INHO there were two things that kept the DA going , good oil and good cooling . Coming from
kart racing I know what a lean run will do , engines DONT GET BETTER .Also lessons lernt
from a previous encounter with a ZDZ 80 showed just how critical good engine temp was .
Every effort was made to duct air flow and to keep a lid on engine temps .
Many many engines later I now have a DLE 111 , DLE 30 and DLE 20 . Using the same care and
attention to detail the DLE engines all have some of the best compression and best power I have
seen from any DLE engine .
As said by others the problems of most DLE come from the users lack of understanding of
ALL the issues at play . The fact that their engines are priced at the first time GAS engine user
does not help there case as a good quality engine .
Give a DLE and a DA to one person and get then to set them up the same way they should
last about the same time . Castig VS machining is a whole other arguement but I will say
that ROTAX and LYCOMING still cast their blocks .
Stu