leo3d

Hi I've found this movment my engine.
The crankshaft moves about 1mm. But the engine runs with no problems o loosing rmps.
I'll post some pics to see the problem.
Anyone can tell me what is this what I must do?

DarZeelon

Leo,


The bearings in your engine must have a bit of clearance to run properly...

If these two photos show the Δ of the front-most and rear-most positions; it seems to be significantly less than 1 mm.


The radial play will be ~1/10 of the axial play and this amount is not noticeable, or is it?

leo3d

Hi Darzeelon, I've just measured the movement, and it is 0.5mm I know it's hard to see in the pics because you have no scale to compare, but I've just did it.
It can easly be moved and mekes a noise when you do that.

leo3d

Nobody from MVVS tech suport? come on guys its serious...

DarZeelon

Leo,


An axial movement of 0.5 mm suggests a radial play of about 0.05 mm.

This is about right for C3 rating of the bearings.
In this engine, the crankshaft is floating in both bearings; not set under some pre-load, as in some F1 racing engines (which reduces axial play to 0).


You did not say that your engine was suffering from any other noise/phenomenon, when it is running.

It seems your engine is OK.

pe reivers

MVVS defines the max axial play as 0.5mm, so it still is OK.
Taking out all play reduced power by 200 rpm in my test engine, so I restored it to original.

leo3d

Thanks a lot, but if the play goes over 0.5mm what must I do?

DarZeelon

Leo,


The play is entirely in the bearings.

It is the front bearing which ultimately limits the amount of play, since it is physically smaller and has smaller diameter balls.

In the presence of sufficient lube (from the fuel, or in sealed bearings, from the grease), bearings have very little wear.
When fatigue sets in, when you become old (....), surface pitting will eventually take place on the races and on the balls, but it will clearly be audible.

If you check the 'play' in one-two seasons, there would probably be no noticeable difference.
If there is (i.e. play has grown), just replace the bearings with identical size ones.

pe reivers

I agree with Dar.
Don't fix it if it aint broke.

DarZeelon

Quote:

ORIGINAL: pe reivers

Don't fix it if it ain't broke.

Thanks, Pé.


But there is another person in these fora who says otherwise...

"If it ain't broke; fix it until it is..."

leo3d

Thanks guys.

duber3

HI!!

AS I said I my previous post, "EVO58X2 OIL", I flew my plane a lot this past week with motul 800 rr at 40:1

Last week I noticed that I had an axial play about 0.5mm, but this weekend I noticed that the play is about 1mm
the engine run fine, but I'm nervous the fly my plane, I'm afraid that somthing will break in the motor, I don't understand why a bearing
can cause this play, I don't see the bearing moving when I move the shaft and when the motor was new, he doesn't had this play

Why the fault is only to the front bearing???

thank!!

pe reivers

The front bearing is secured in the housing with lock tite. It may need a small shot if the same?
Hot engine running may cause the locktite to loose it's fastening properties, so please do check your cooling.
I know, you think the engine is cooled well, but is it?

duber3

I read in your previous post that if the engine is not cooled well the front seal
will leak, but mine doesn't leak and the engine is in a warbird " F4UCorsair"
I flew the plane mostly at half trottle, anyway is it dangerous this movement??

I read on your forum that mvvs has change the front bearing due to constumer critics
is this the same problem with the evo???

thank!! your help is very appreciate!!!

pe reivers

I have no data on the play and allowed play that the evolution engines should have.
I think you should contact Horizon if you need to be sure.
1mm is a sign that the bearing is loose in the housing, though the seal still can be good. MVVS does not recommend customers to work on the engine because of some critical torque features inside. New engines have sealed cylinder bolts, and tamper-free connecting rod nuts for just that purpose. Again, I do not know about Evolution, but sound reasoning tells me it would be the same.

duber3

Thank!! I will send the motor to Horizon
I will post back when I will have news from horizon

thank you!!

duber3

Hi Pe!

I received my engine from Horizon
here what they have changed

Front bearing
Connecting Rod Washer
[link=http://www.horizonhobby.com/Products/Default.aspx?ProdID=EVO3001I1101]Prop Drive [/link]

I have'nt flew the plane yet, the winter is about to beging

I will post back next summer in 2009

bye!

pe reivers

I don't see why they should replace the washers, unless they damaged them? The prop drive just pops off without damage and can be used again and again. The connecting rod washer is a different story. One small mistake, and it's gone. You need qualified personell to do that job right.

duber3

I've flew my plane a lot this summer (2009)
not sure if the problem is gone, it seem there a little tiny play on the crank shaft

for the rest the motor run very good

pe reivers

There should be some play. Remove it, and you loose 200 rpm!
Been there!

PS,
A drop of oil to the seal's sealing lip helps a lot in keeping the engine front healthy. Once the seal is run in properly that will become less important. If the prop turns obstructed, lubricate that seal lip! The oil supplied from the fuel mixture mist sometimes is not enough. Especially in very lean oil mixes some folks believe in.

FLAPSDOWN

PE,

Do you have a Liquid Cooled 58 and radiator in stock or can you tell me how long it may take to get one. Also, what are the current costs?

Thanks.

Bill

pe reivers

working on a drawing of the cooler I have in my hands right now.
Be patient please, will get back to you ASAP.
Engine availability is good, though they are assembled on request only. Takes a couple of weeks.
Cost etc. on my web pages www.mvvs.nl

pe reivers

Done, hope I can upload a file. Hmm quality is lacking. Will try again.