Alessandro 78

Hi all,

I have just picked up the above mentioned engine.
It has only few tanks of fuel, but the main problem is that the owner did 2 drill holes to the crankcase to try to remove the inner cam shaft bearing. because it was blocked.

I'd like to buy a brand new crankcase.
Tower hobbies has one:

http://www3.towerhobbies.com/cgi-bin...?&I=LXCG97&P=Z

but i don't know if it can be used (the engine is really old).

the old one has a label between the mounting holes that says: "NH" (or "HN", it can be red from both sides)

can someone help me??

many thanks

Alessandro

Vertical3-D

My Feedback: (20)

posting a pic of your engine would help, thats a pretty clear pic from tower, do they look the same?

Ram Jet

Could the holes be "tacked" over with a spot heli arc weld?

Bill

gkamysz

My Feedback: (19)

I'll check for you. I have 5 or 6 of the old 1981 FS-40 and a few of the FS-40S. Most parts in the block are interchangeable. Crank, piston, rod, carb, I'm pretty sure the Surpass case will work. If the holes aren't too large I would just fill them with epoxy. If you have a photo that would be helpful.

rainedave

My Feedback: (1)

You might also watch the RCU market (and other places) for a used, worn out cheapie and cannibalize it for parts. I do this sometimes for impossible to find parts like prop drives, etc.

David

mike109

G'day I have an early OS FS 40 which I suspect is like yours. Mine has NC under the engine mounting lug. It has the letters OS on one side of the engine and FS-40 on the other side. It does not have Surpass anywhere. I suspect that your engine is like mine and that the crank case you have seen for sale is not suitable. Many of the parts are interchangeable. I think the bearings are the same and the piston ring also.

If you want a "new" crankcase, your best bet is probably to find a good used one. I would be suprised is there are still any new ones out there for sale.

The FS-40 is one of the sweetest running little four strokes you will find. Not one of the most powerful but very easy to use.

I have had the one in the photos for many years. I most recently had it in a very old Kadet Senior which it flew. Just.

I agree with a previous poster - I would try to repair the holes with 24 hour epoxy. The holes in that area would not be structural.

submikester

My Feedback: (6)

I would give JB Weld a try. I have literally held engines together with the stuff in my younger days...now I crash far less

Motorboy

In case the old crankcase are necessary to be replaced with modern crankcase (Surpass) of current production, the new crankcase with the shorter distance between valvelifter is an obstacle for the old camshaft with thick gears.

It needed to use the newer crankcase (Surpass) we must have new cylinder head + cover for valve and camshaft as well. The rest of all the old parts fit in recent crankcase.

Sometime are the old FS 40 to sale in EE-BBAAYY. Use it as a spareparts, it is cheaper than to replace with new parts.

I has both FS 40 and Surpass FS 40.

Edit: corrected some wrong word..

w8ye

My Feedback: (16)

The letter codes you guys are quoting like "NC", "NH", or "HN" is a code of who assembled the engine at the OS factory. The letters are more or less meaningless to us as consumers. A new crankcase does not have these assembly code letter sets. So if you see a OS without these letter codes on the bottom of one of the mounting lugs, it means someone replaced the crankcase with a new part.

Alessandro 78

Hi all,

first of all many thanks for your quick reply.

here below the pictures.

The JB weld seems the best way after all.
The problem is that here we have different stuff. I'll try throgh TH.

Alessandro

Patxipt

Buy some metal epoxy and you just have it fixed.

Something along these lines
http://www.huntsman.com/advanced_mat...fm?pageID=5901

gkamysz

My Feedback: (19)

Jens, is right. The pushrod area of the case is different. So they would not be interchangeable. Those holes are small. Just fill them.

Motorboy

Or use ballbearing with rubber shield at one side..

Vertical3-D

My Feedback: (20)

did the previous owner ever get the bearing out, just wondering why he was trying to replace it...if you heat the case with a torch(not to much though) it'd probably almost fall out, any cold weld epoxy should fill them, just make sure the case is very clean first so it adheres well

Alessandro 78

Hi all,

a little update.
The previous owner did the holes recently after about 15 years after the breake in: the cam shaft bearing was blocked and there were no way to remove it.

anyway, I did the repair: i used a product called "lquid metal", a single part putty used to fill gap into car's exsaust systems.
As soon as it become hard (about 12 hours), it can be also polished!.

the job went well for me. have alook to the picture attached.

Now I need:

a new piston ring (missed years ago)
a new connection rod (piston to shaft) because a little bent
a new set of bearings (i want to be prepared after the secon brake in, just in case)

Many thanks to all for the usefull info.
Ill' post the result as soon as it runs again. And then, if everything goes well, i have to find an airframe

bye

Alessandro

Motorboy

Use same parts number as in we has in the new OS FS 40 Surpass as here: http://www.gpdealera.com/cgi-bin/wga...pgm?I=OSMG0845

Alessandro 78

Hi friends,

it runs!!

Preatty well too.

it isn't a powerhouse. The first readings after 1 and a half fuel tank are:

master 9x6 7.050 rpm
master 9x8 6540 rpm
zinger (wood) 10x6 6.000 rpm

I need some more test and fuel to complete brake-in the engine.
I plan to mount it into a small bipe, may be the small tiger moth from Gee Bee models (i have a copy of the drawing).

here below a couple of pictures.

bye
Alessandro

Patxipt

Alessandro, congrats on the engine![8D]
Those numberes seem to be a bit low, my FS-26 runs those prop sizes (mainly Master, too) and higher rpms. I know the FS-40 isn't a powerhouse, but still, it ought to turn them at a bit higher rpm... How's the valve clearance?

asmund

They seem VERY low. My ASP .30 fs did swing MAS 9-6 at 11300[X(]

gkamysz

My Feedback: (19)

Verify that the camshaft has been timed correctly.

jaka

Hi!
That's very low rpm !
I had one of those 25 years ago (still have a Nib lying in a box) and best prop was a 11x6 in a 130-140cm span low winger weighting 1,8kg

Alessandro 78

I'll check again the cam. [&:]

in a couple of days i'll do another try.


Alessandro

ace4-40

I wouldn't even worry about the holes. The case is open to the atmosphere through the breather so two more small holes won't make any difference. As a matter of fact they will ensure the cam bearings and shaft will have positive lubrication as the oil from blow by will move towards those holes. The only real draw back is oil coming out through them and no way to direct if away from the engine. If you really have to plug them, clean well with a solvent and use JB weld or some other type of epoxy.

Alessandro 78

Hi all

First, merry Christmas to everyone.

Today, before going to have the usual Christmas lunch, I tried the engine again, after having corrected the timing of the cam (last Sunday night).

Well, the reading now are a little better

MA 9x6
• Rpm Min 3340
• Rpm Max 10020

Zinger 10.5x7
• Rpm Min 3500
• Rpm Max 7800

In the next days I have to tune a little better the needle and balance the propeller, but I have to admit that I like this engine: greate transiction a good power.
Basically it is still brand new (only 3 fuek tanks at the moment, considering also the one that my friend did 20 years ago; he admitted that he bought it in the early '80).
Next step is find a (new) model for it .

what about this one??

http://shop.lindinger.at/product_inf...ducts_id=72974

Thanks all for your support

Bye
Alessandro

w8ye

My Feedback: (16)

Alessandro

I think your engine will pull a 10 X 6 prop also

The Beaver should be OK but is set up for electric. You will need to reinforce the firewall for a glow engine and buy a engine mount.