franchi

Hi Gang:

I would like your opinions of the above engine. I sawone relagated to the scrap heap yestereday and asked why. I was told that they aren notcompetive in any events any longer. I guess that is accurate. For my use, it is a good sport engine for smaller stunt/sport planes but who wants to mess with a Diesels now that ether is difficult to obtain.


Any comments?


Franchi

AMB

I hope you pulled it out someone can use it ( I have 3 so I do not) martin\\

For us one the site I do not think the comment that went with the toss is worth a response lets just keepum flying gang

gkamysz

My Feedback: (19)

The engine is a 30 year old design. It is outdated. Newer engines are more powerful and lighter. It just depends on what a person needs.

gcb

I like the two that I have.

George

Jim Thomerson

Here is a copy of  my post on the MVVS .15 propeller thread..

The MVVS 2.5 cc, Aeromodeller, Aug.,1997, has a different shaped torque curve; peak torque is almost 30 inch-ounces at 17,000 RPM. Peak horsepower is 0.56 at 20,000 RPM. Said to turn a 10 x 3 at 10,000, but peak torque prop woud be an 8 x 4 at 16,200. Peak HP would be a 7 x 4 at 19,300. So this is not a slogger.

Doesn't sound too shabby to me.  I had the opportunity of bench running a couple which were giving a friend problems.  I was impressed. But then I am used to flying ST G20-15D's which turn an 8 x 4 in the 14,000-15,000 range. 

NM2K

My Feedback: (14)

Me two - er - too! <G>


Ed Cregger

gcb

Franchi,

What are you doing to the message line that extends it longer than normal? I must scroll to read your entire message.

MVVS has always been a good engine. In addition to the two .15D's, I have a .15 glow and three .09 diesels...all run well. I do not have any of the larger MVVS's.

For your CLStunt ships, one method is to pick a prop that works with your plane, then power it with an engine that will sufficiently turn that prop.

Don't choose a prop just by running level, try it in maneuvers. You need a prop that will pull your plane out of square and overhead maneuvers. Sometimes a small diameter high pitch prop will not work as well as a larger low pitch prop, even though it is not at peak onthetorque curve. Experiment!

Many engines over the years have been "top competition" engines...until something better comes along. A lot of it is cubic money. You can't run a production engine against high-dollar specialty engines and expect to win. That's why there are competitions that limit the engine and plane so the average person can compete and have fun.

Fly your MVVS and have fun. Oh yes, if you didn't already, salvage that MVVS if you can!

What do you mean by "ether is difficult to obtain"? That's true in many parts of the world, but in the USA we can buy ready-mixed fuel or, if you want to mix you own, there are high ether content starting fluids available. Try Eric Clutton (Dr. Diesel), or Ed Carlson (Carlson Engine Imports), or Bob Davis (Davis Diesel Development).You can also buy directly fromAerodyne or Red Max.

I would recommend using ready mixed...at least at first.

George

paw080

Yes Franchi, MVVS 2.5D's be plenty good. I still want to mess about with Diesels,
because dey be plenty powerful.


tony g

fiery

My Feedback: (2)

Pe Reivers recently sold me a new Piston and liner set for an MVVS 2.5 cc diesel I acquired "pre-loved" (from an old gentleman who sadly is very ill). It appeared to have very little use though the piston and liner in it felt awful when turned over and would not hold compression. It was sitting neglected and sad when I collected it

The engine stripped, cleaned and assembled with new piston and liner and placed on a test stand today. Purpose - first start and running in.

Fuel: 25% Castor Oil; 35% Di-Ethyl Ether; 1.5% IPN; balance lighting grade Kerosene.

After a few minutes flipping and gradually screwing down the tommy bar, it started to pop. Open exhaust - no silencer fitted (I do not fit silencers to engines I am running in).

A quick touch of the electric starter - and it was away. Brrrp ....brrrrp .... brrrp running very rich (3 1/2 turns out on main needle)

Several very rich 5 minute runs followed. Complete cool down to ambient temperature between runs. Engine starts to feel "bouncy" as the moving parts bed in. Still can't hand start it though. Compression feels good.

Contra piston is an extremely tight fit. I use my "broomstick" handle compression adjuster to turn in the compression screw. There is no blow by leaking out past the compression adjusting screw. These MVVS engineers and machinists know their business.

Lean out to rich max RPM and adjust compression carefully for best running. Back off 1/16th turn. I lean it out to see if will hold a peak. All is good. Quickly richen up. Try R/C carb. After screwing out the air-bleed adjustment screw to max, it throttles like a good glow engine.

One VERY happy MVVS small diesel owner. Onlookers (mostly electric flyers) are impressed.

Basic data :

+ Temp: 13c

+ Elev. 200 meters AMSL

+ Humidity 65

+ Barometer Not Known

Engine

MVVS 2.5D "Blue Head"

Propeller: Bolly Clubman 8.5 x 4

Fuel mix: As above

Max RPM after several tanks (quick and dirty effort, run in not yet complete): 12,500 on R/C Carb fully open

Min - not checked (engine not run in nor settings optimised)

HWM77

Hi allways on the look for old MVVS 15D piston/liners,any one have any spares, Thanks

AMB

I received an E mail from Pe Rievers 2 days ago. He has some new ones, do not know his parts inventory, the engines I think under $100, ( it is $94 US) thus a parts source, the sum of parts
may be close to buying a whole new engine which can be used for parts, then again save the old for parts carby, crank, etc and use the new one martin

fiery

My Feedback: (2)

Picked this NIB MVVS 2.5D R/C up from my LHS a few weeks ago. I already have one (mentioned above), but, at the price I was given I had to take it .

AMB

Fiery very nice find, think I am quitting at 3 , but you never know a good deal may just show up here, the elctric guys are always impressed
with the little diesels just the fuel, flip and go thing martin

hmmm nice color coordination head matchs the dress

earlwb

Yes for serious competition the MSVVS .15 might be obsolete. But it is still great for things like sport flying, stunt, free flight, and so on. it would be a good engine for things like beginners just getting into things like team racing, etc. and other events too.
Then as one's skills progress they can decide to invest in the higher performance engines for serious competition.
Someone just getting into competition doesn't need a Cyclon or other high end engine to compete with. There are thousands of little things and details one has to perfect before a high end engine would do them any good. Plus just getting a high end engine doesn't mean it will run any better right out of the box either. You still have to tune and adjust the engine to get it to run good.

DeviousDave

I consider the .15D to be a drop in replacement for a modern glow .15. Sure, it's a diesel and will swing props that a glow motor of the same size wouldn't be capable of, but it is timed to run fast. They were marketed as ducted fan motors if that tells you anything, and the glow version held the US .15 Quarter Midget record at the time they switched to .40's. Not every diesel is meant to go on an old timer, that's for sure-even at 30 years old, the MVVS's are still relevant. Maybe a touch heavier than a glow .15 but just as powerfuel. I don't think an OS .15FP would turn a 7-4 as fast..

I have a few of these, ran one of them recently and posted video here. I had low expectations because of their "clunky" appearance and was happy to be very wrong. The engine is a sweet runner, starts easily and made good power. Now I want a new one with the pretty clue anodizing, it's a lack of free funds and a greater desire for a PARRA that are stopping me.

fiery

My Feedback: (2)

Ran in engine shown above by my ladyfriend.

Easy. Six four to five minute runs, with complete cool down in between.

Four flick starts were the norm once a good "rich and slightly undercompressed" setting was found.

As a seventies design it is no longer "state of the art". However, it is a tractable well priced sport engine with power and long life, if well treated.

AMB

Fiery sounds good ( I have 3 of the MVVS15Ds). I think we sometimes may overdue the "state of the art thing') I do not think anything out there remains state of the art, there is always tweeks and not only of course in our engines, medicine,electronics just a couple of other examples, the fact is if it works and fills our needs that is what counts, cell phones a good example. Are you going to buy
a new one every6 months for the latest add-on?

I would guess over 90% of the folks that fly are sport or scale, So the Ferrari"s of model engines not required, competition a whole other game and not getting into that one we just require a well made engine easy to set up and stay together
If in the 15 class or so the Fox 15 with Davis head , easy to obtain, no parts availabilty issues, the classics PAW, of course the MVVS is the great mystery are they going to make more?? If you have the bucks the Tiapan super engine
I just like the easy thing fuel-flip-fly

Best to all and have a great Super Bowl day GO GIANTS martin

Do not take this as me being negative to progress with my head in the sand medical advances save lives, in navigational great strides, flying safer,

pe reivers

I just had a talk with MVVS concerning the .15 diesels. They still have a decent stock of assembled engines, with parts to match. For the time being, no new production runs are planned.

I then ran my steel cylinder original test engine using 10/40/50 (oil-ether-kero) open exhaust, 3.5mm venturi with .15 carb NVA.
The oil is a Castor/synthetic racingblend for kart use.
props: MA series-3 (wider blade)
9x4 12,000 rpm (0.29hp)
9x5 11,000 rpm (0.28hp)

The timing of this engine differs quite a bit from the glow engine timing
the converted glow engine turned the 9x4 prop at 11,200 rpm with same 3.5mm venturi setup. The engine not run in yet, and tended to sag on a lean full power setting. Slightly richer it would hold the 11,200 steady. My fuel does not permit high rpm testing, so I left it at that.
Need to get some Amsoil cetane booster (amsoil is 100% di-ethylmethyl nitrate)

Recycled Flyer

Hi Pe´,
Inote well the careful use of the words "For the time being..."

Sounds like there is more of a chance that the diesel range may get a rerun than the glow series.

Thanks.

AMB

Recycled flyer My guess also they may stop production of of the others but will bet on re-runs of the 15D, martin

pe reivers

They have 30 diesel engines in stock + a decent number of liner/piston/conrod assies. No need for a re-run.

peterburford

Interesting to note how few diesel engines are now considered adequate manufacturer's stock.
Peter