So many home made experts, it's no wonder many of the real experts and people that I learnt much from don't visit here anymore

Karol

Its true !!

Only comment I made was that I did not like the port machining. Engine may run just fine the way it is, but " personally ", I do not like the quality of the machining.

Not speaking from experience with model gas engines, but I am speaking from experience with snowmobile racing engines. If we ever had a snowmobile engine with such poor quality machining, we definitely would not be putting it into a race sled. If by mistake we did, then two things would most likely happen and that is, we would loose the race or the engine would blow up.

Enough said on this subect. [&o] Lets move one.

Ganpooba, don,t expect our low priced RC engines to be on par with a Snowmobile race engine. I have seen both insde. My cousin from Casnovia Mich had a dyno & built race engines. His boys run the race sleds and they held the Worlds fastest record for 10 years straight. I got a news paper to prove it.

Capt,n

It's his engine Tim. He disassembled it at checked out the ring end gap, etc.

Toolmaker says it needs a new ring....Tim Ble is wondering how Toolmaker can say that!

That is the way I read it???? Not sure!!!!!!!!!

correct. none of those pictures shows a need for a new ring so how did he arrive at that conclusion

IL can report my engine certainly needed a new ring. It was one of the early units with "bad" ring. The problem was too much outward tension on the ring, causing excessive wear. Dimensionally the ring was all over the map - the radial thickness varied greatly, and there was a large gap in places on the back side of the ring, promoting leakage around the ring. The original ring was worn out in 1 gallon of fuel. Compression was almost zero, and starting was beginning to be difficult.

I put in a Frank Bowman ring. Compression immediately went up to at least where it was when the engine was new, and max RPM on a Falcon 17-6.5 CF went from 8300 (at its best as built) to 8900 rpm. The engine is now VERY powerful, and I would be fitting a larger prop if I was using engine at full throttle much. I don't think there is a DLE 20 anywhere that can touch the power of this one.

Other than the ring, I actually thought the machining inside the engine was quite good. I think some are looking at the Nikasil coating (same as Porsche 911 engine) and noting that it looks a little different than a conventional steel or iron liner. I am sure there is no hand grinding going on with this bore.

Just look at the picture of the piston and the wear pattern on the ring.No more comments for me I don't want to upset you experts.

If you are referring to post #15 (only post on the thread that shows the piston) there is not even a ring installed on the piston, so not possible to comment on wear pattern of same.

Yup, that is what I see too.

By the way, thanks to Captn for posting the photos of the internals of the engine. Certainly interesting machine work on the crankcase. I don't see anything especially out of the ordinary about the cylinder though.

My Apology I missed it

No problem toolmaker. You are correct in referring to the machining marks on the piston, however. Mine was exactly the same. Doesn't seem to matter though, as this piston and mine had no wear or scuffing on the skirt of the piston.

Ditto that as mine was exacty the same. Just to mention that my G20 after several gallons of fuel still has similar machining marks on the piston skirt. Also remember that when we use the enlarge facility to look at the picture of the piston posted by Capt,n be aware that it magnifies the piston and all other disernable features by approx. 300%.

Karol

It is good to see the lathe/machine marks...if wear was taking place the machining marks would be gone in that area. Some real big pistons are cam ground and appear much smoother. A cam ground piston is done too control dimentions of piston due to temperature.

Those pictures posted show a perfectly normal looking Mintor engine. Dimensionally its hard to comment but the maching marks and bore hone marks are all normal

Capt,

You do not have to show me a news paper to prove it as I beleive you ! Besides the NEWS MEDIA never lies.

www.youtube.com/watch

[youtube]http://www.youtube.com/watch?v=Kc5Nxk8oMyE&list=UUFNvLj4yhlskZvRxsQec DFA&index=1[/youtube]

[youtube]http://www.youtube.com/watch?v=0C5xk...DFA&index=[/youtube]

Good motor

It's nice to see that after being so very aprehensive about the engine earlier you have come to this conclusion, which I am assuming is based on the fact that you have been running it.

<font face="Arial">Good function 8400RPM</font>
<font face="Arial">Neither case to the gossips</font>

Looks like Okinox has several videos to view. He is even getting better at landing it seems. Good job. Keep the videos coming....of Mintor powered planes for sure!!! Best Regards Capt,n

<span style="font-family: Verdana, Arial; font-size: 13px; background-color: rgb(251, 252, 255);">Goods fly my EXTRA 330S Phoenix Model 1650mm. Mintor22 was 8600RPM with APC17x6 not fail in fly never. Vertical fly to fast.</span><br style="font-family: Verdana, Arial; font-size: 13px;" /><span style="font-family: Verdana, Arial; font-size: 13px; background-color: rgb(251, 252, 255);">I am delighted with my engine, great sound&iexcl;&iexcl;&iexcl;</span>

We all are very happy for you, continue to enjoy your Extra and Mintor 22.