Hi Nick,

Comments interspersed below:

WRB

On Apr 19, 2009, at 19:12, nick.king88 wrote:

>  1946 415C
>
> I just raised the mains and removed the fairings.  How do I service 
> the oil and what kind do I use?

You can jack the plane inboard of the main gear directly under the 
front spar until the tire is about 3-1/2" off the ground.

Remove the nut and clevis bolt at the bottom of the oleo attaching it 
to the lower gear leg .  Swing the oleo rearward to clear the bumper 
block and slide the oleo cylinder/donut assembly down and off the 
piston.

For Serial No. 1498, your MLG oleos originally used red hydraulic oil 
and were sealed with AN 6227-17 O-rings at the bottom
of the piston (see Ercope Parts Manual p. 14, Fig. 12, Items 16 & 15).  
Since the oleo parts do not rotate, wear tends to
change the shape of the inside of the oleo strut cylinder (Item 23) 
from round (which an o-ring can seal) to an oval
(which an o-ring can't seal).  This problem can be resolved by 
reworking the piston to take the rubber cup seal (see
P. 12, item 8a) used in earlier Ercoupes.  Make sure the orifice in the 
bottom of the piston is not clogged.  Oleos with this
modification use automotive brake fluid.  Once you know what you have 
(or need), note it and, in future, have replacement
in hand before disassembly.  Do not re-use O-rings or cups.

> The washer/rubber stack looks good and measures 4".  The tail is 3" 
> low.  I have a single fork front.

The fact that you still have the original single-fork nose strut is 
promising, but not conclusive.  There were single forks for 5" and 6"
nose wheels.  If it mounts the original 4" wheel and tire, your tail 
should not be low unless your rubber donuts are old, hard and 
compressed.  The donut stack should completely fill the space between 
limiting flanges on the cylinder.  It can be challenging to replace the 
donuts and reassemble the stack on the cylinder, but periodically 
necessary.  A press, screwdrivers, dexterity,
confidence, patience and experience all help.

> What is the small (looks like an old oil flipper) on the main strut?

That is where excess oleo fluid flows out.  After fitting a new cup or 
O-ring, I pour fluid in the oleo until it runs out.  I coat the seal 
with fluid and start the piston back down into the cylinder, adding a 
squirt or two more fluid from an oil gun until it runs out again and 
then work the cylinder back down into the cylinder until it is possible 
to re-attach the oleo to the lower leg with the clevis bolt, nut and a
new cotter key

> Should I install the "spacer"?

Not unless your tail is low after replacing the rubber donuts

> What is the procedure for filling the front strut?

There is a filler plug in the top of the strut with a gauge wire on it. 
  With the tail weighted down and the nose strut extended, you fill it 
to the red mark.  When the plane is sitting normally on all three 
wheels, fluid should come to the green mark.

> Is it the same type of oil?

Use red hydraulic fluid.
>
> I also have a leaking push rold tube can I re-align it or is it best 
> to put a self sealing tube on it? What would you recommed?

Sometimes these can be re-rolled successfully.  Alternatively I believe 
the REAL gasket company makes something that works.
>
> I have an extensive mechanical background and am very capable of doing 
> professional work that I trust.  This little coupe, that I have 
> quickly learned to love, presents me with a new learning curve.  With 
> your help I look forward to bringing her back to excellent condition.

As Al suggested, you're going to need to get and become familiar with 
all the manuals.
>
> Continued thanks,
> Nick

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