oil leak question

[Dick]

My Continental 85 is leaking oil and appears to be from pushrod tubes and
valve covers. It is on an experimental plane.

While I can cure the one leaking valve cover, the pushrod tubes have those
heavy "wirecircles with two tangs" over the rubber end fittings. Some tubes
are leaking at bottom and others at top with no discernable pattern to the
leak locations.

Are there any after-market clamps (installable like a hose clamp hopefully)
that would be able to replace the originals?

Is there any "non-teardown" fix? Wondering along the line of front wheel
drive vehicle axle constant-velocity joints and the split-boots sometimes
used.

I did notice that the intake tubing joint rubber fittings had substantial
screw clamps. However they don't appear to be workable for the tubes.

Would appreciate some thoughts,
thanks,Dick

[Bushy]

As it's experimental you might be able to get away with something you make.

There are aftermarket VW pushrod tubes that screw together to install and
then unscrew into position and clamp against their ends and their rubber
grommets rather than the head off routine required with standard tubes. You
then reinstall the pushrod.

Don't know how these would compare to the Continental engine.

Hope this helps,
Peter

"Dick" > wrote in message
om...
> My Continental 85 is leaking oil and appears to be from pushrod tubes and
> valve covers. It is on an experimental plane.
>
> While I can cure the one leaking valve cover, the pushrod tubes have those
> heavy "wirecircles with two tangs" over the rubber end fittings. Some
tubes
> are leaking at bottom and others at top with no discernable pattern to
the
> leak locations.
>
> Are there any after-market clamps (installable like a hose clamp
hopefully)
> that would be able to replace the originals?
>
> Is there any "non-teardown" fix? Wondering along the line of front wheel
> drive vehicle axle constant-velocity joints and the split-boots sometimes
> used.
>
> I did notice that the intake tubing joint rubber fittings had substantial
> screw clamps. However they don't appear to be workable for the tubes.
>
> Would appreciate some thoughts,
> thanks,Dick
>
>

[Bela P. Havasreti]

On Wed, 17 Nov 2004 12:03:14 GMT, "Dick" > wrote:

Real Gaskets Corp. makes an STC'd retrofit pushrod tube replacement
kit that you can install without removing the cylinders. You pull the
pushrods, remove the old tubes by cutting them in half with a Dremel /
cut-off wheel or whatever and the new ones go in with a spring ala a
Continental O-470 style pushrod tube.

I have a kit on my C-145 and am happy with it.

See: http://www.realgaskets.com/files/horizontal.htm

It's part # RG-200PRT-1

Bela P. Havasreti

>My Continental 85 is leaking oil and appears to be from pushrod tubes and
>valve covers. It is on an experimental plane.
>
>While I can cure the one leaking valve cover, the pushrod tubes have those
>heavy "wirecircles with two tangs" over the rubber end fittings. Some tubes
>are leaking at bottom and others at top with no discernable pattern to the
>leak locations.
>
>Are there any after-market clamps (installable like a hose clamp hopefully)
>that would be able to replace the originals?
>
>Is there any "non-teardown" fix? Wondering along the line of front wheel
>drive vehicle axle constant-velocity joints and the split-boots sometimes
>used.
>
>I did notice that the intake tubing joint rubber fittings had substantial
>screw clamps. However they don't appear to be workable for the tubes.
>
>Would appreciate some thoughts,
> thanks,Dick
>

[jls]

"Bela P. Havasreti" > wrote in message
...
> On Wed, 17 Nov 2004 12:03:14 GMT, "Dick" > wrote:
>
> Real Gaskets Corp. makes an STC'd retrofit pushrod tube replacement
> kit that you can install without removing the cylinders. You pull the
> pushrods, remove the old tubes by cutting them in half with a Dremel /
> cut-off wheel or whatever and the new ones go in with a spring ala a
> Continental O-470 style pushrod tube.
>
> I have a kit on my C-145 and am happy with it.
>
> See: http://www.realgaskets.com/files/horizontal.htm
>
> It's part # RG-200PRT-1
>
> Bela P. Havasreti

Real gaskets are out of sight. I make my own from silicone sheet. You
can too and save 8 bucks apiece or just use the right kind of stock gaskets
and a high-quality gasket seal on the valve covers. Cross-tighten evenly
and not too much torque. 20-30 inch-pounds is usually enough.

480 bucks for pushrod tubes? Outrageous. Unless you have money to burn.
No offense to Bela, of course. Just re-swage the old ones on the cylinder
ends. It can be done without removing the jugs. If the leaks are around
the pushrod tube bosses on the crankcase, I'd still pull the jugs and
replace the boots to save $80 per cylinder. Buy you some good clamps. I
use spring clamps. I have never seen a boot get old and wear out, but then
I guess everything is mortal. Even Barnyard Boob.
>

[Bela P. Havasreti]

On Wed, 17 Nov 2004 12:45:51 -0500, " jls" >
wrote:

>
>"Bela P. Havasreti" > wrote in message
...
>> On Wed, 17 Nov 2004 12:03:14 GMT, "Dick" > wrote:
>>
>> Real Gaskets Corp. makes an STC'd retrofit pushrod tube replacement
>> kit that you can install without removing the cylinders. You pull the
>> pushrods, remove the old tubes by cutting them in half with a Dremel /
>> cut-off wheel or whatever and the new ones go in with a spring ala a
>> Continental O-470 style pushrod tube.
>>
>> I have a kit on my C-145 and am happy with it.
>>
>> See: http://www.realgaskets.com/files/horizontal.htm
>>
>> It's part # RG-200PRT-1
>>
>> Bela P. Havasreti
>
>Real gaskets are out of sight. I make my own from silicone sheet. You
>can too and save 8 bucks apiece or just use the right kind of stock gaskets
>and a high-quality gasket seal on the valve covers. Cross-tighten evenly
>and not too much torque. 20-30 inch-pounds is usually enough.
>
>480 bucks for pushrod tubes? Outrageous. Unless you have money to burn.
>No offense to Bela, of course. Just re-swage the old ones on the cylinder
>ends. It can be done without removing the jugs. If the leaks are around
>the pushrod tube bosses on the crankcase, I'd still pull the jugs and
>replace the boots to save $80 per cylinder. Buy you some good clamps. I
>use spring clamps. I have never seen a boot get old and wear out, but then
>I guess everything is mortal. Even Barnyard Boob.
>>

No offense taken.... I hear ya (and for the most part agree). I
bought the re-swaging tool from (I think) El Reno aviation, and
re-swaged all the pushrod tubes on the left side (port side for you
mariners) of my C-145-2, but one cylinder still leaked. So I only
bought (1) Real Gaskets pushrod tube kit to fix that 1 cylinder (I was
tired of it leaking).

I wish the kits weren't so expensive. I have no affiliation
what-so-ever, but still think it is a superior design than the
original (Continental finally fixed their pushrod tube design
faux pas with the O-470).

A friend just rebuilt a C-85 and sprung for RG pushrod tube kits for
all 4 cylinders. I'm sure he didn't particularly like writing the
check, but wanted to make the engine more serviceable while
it was all apart.... 1000 hours down the road or whatever, it'd
be nice to just compress the spring, pull the offending pushrod
out and replace the seals to fix any future leaks.

Bela P. Havasreti

[Jim Weir]

PLEASE don't do it this way. Remove them the old-fashioned way. Cut that tube
off with a saw and I guarantee you chips in the oil pan. Not good.


Jim



You pull the
->pushrods, remove the old tubes by cutting them in half with a Dremel /
->cut-off wheel or whatever and the new ones go in with a spring ala a
->Continental O-470 style pushrod tube.


Jim Weir (A&P/IA, CFI, & other good alphabet soup)
VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
http://www.rst-engr.com

[Morgans]

"Jim Weir" > wrote in message
...
> PLEASE don't do it this way. Remove them the old-fashioned way. Cut that
tube
> off with a saw and I guarantee you chips in the oil pan. Not good.
>
>
> Jim

Couldn't one push a piece of cloth rolled in a ball down the tube, past
where it is to be cut, and contain the shavings?

Don't jump me, it is just an idea; wondering if it would work.
--
Jim in NC


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.797 / Virus Database: 541 - Release Date: 11/15/2004

[Dick]

As food for thought...
seeing the spring loaded pushrod tube referenced by Bela makes me wonder if
some kind of external spring could be installed over a tube (without
removing the tube) and press against some sort of seal applied linearly at
both ends; kind of like teflon string (as opposed to tape) that plumbers
use.

just changed the toilet inlet valve and saw the
shank washer just seal the valve body with finger tightness..

if not a spring, how about some sort of clamp over the tube that would hold
the hand fabbed string gasket tightly in place?

Since this is an experimental, what does everyone think??

thanks, Dick

http://www.realgaskets.com/files/horizontal.htm
> >>
> >> It's part # RG-200PRT-1

[Bela P. Havasreti]

On Wed, 17 Nov 2004 17:36:03 -0500, "Morgans"
> wrote:

>
>"Jim Weir" > wrote in message
...
>> PLEASE don't do it this way. Remove them the old-fashioned way. Cut that
>tube
>> off with a saw and I guarantee you chips in the oil pan. Not good.
>>
>>
>> Jim
>
>Couldn't one push a piece of cloth rolled in a ball down the tube, past
>where it is to be cut, and contain the shavings?
>
>Don't jump me, it is just an idea; wondering if it would work.

I'll see if I can find the original instructions, but I think that's
how they suggest you do it. If I find the instructions, I'll
post back what it says.

What I did is use vise grips to collapse the tube near the outer
end (where it enters the rocker arm area). The metal is fairly
soft, and easy to deform. A small cut-off wheel on a Dremel
makes quick work out of cutting the tube in two at about the
same location.

There are no metal chips scattered anywhere with this method, just
a small amount of residual aluminum and abrasive wheel dust
associated with the cutting process.

Bela P. Havasreti

[Nathan Young]

On Wed, 17 Nov 2004 23:19:08 GMT, Bela P. Havasreti
> wrote:

>On Wed, 17 Nov 2004 17:36:03 -0500, "Morgans"
> wrote:
>
>>
>>"Jim Weir" > wrote in message
...
>>> PLEASE don't do it this way. Remove them the old-fashioned way. Cut that
>>tube
>>> off with a saw and I guarantee you chips in the oil pan. Not good.
>>>
>>>
>>> Jim
>>
>>Couldn't one push a piece of cloth rolled in a ball down the tube, past
>>where it is to be cut, and contain the shavings?
>>
>>Don't jump me, it is just an idea; wondering if it would work.
>
>I'll see if I can find the original instructions, but I think that's
>how they suggest you do it. If I find the instructions, I'll
>post back what it says.
>
>What I did is use vise grips to collapse the tube near the outer
>end (where it enters the rocker arm area). The metal is fairly
>soft, and easy to deform. A small cut-off wheel on a Dremel
>makes quick work out of cutting the tube in two at about the
>same location.
>
>There are no metal chips scattered anywhere with this method, just
>a small amount of residual aluminum and abrasive wheel dust
>associated with the cutting process.

If it is thin enough to bend with visegrips, could you cut it with a
set of large bolt cutters?

[Morgans]

"Nathan Young" > wrote

>
> If it is thin enough to bend with visegrips, could you cut it with a
> set of large bolt cutters?Or, is there enough room to rotate one of those
little pipe cutters. No residue at all, from that.
--
Jim in NC


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.797 / Virus Database: 541 - Release Date: 11/15/2004

[Bela P. Havasreti]

On Thu, 18 Nov 2004 00:02:17 GMT, Nathan Young
> wrote:

>On Wed, 17 Nov 2004 23:19:08 GMT, Bela P. Havasreti
> wrote:
>
>>On Wed, 17 Nov 2004 17:36:03 -0500, "Morgans"
> wrote:
>>
>>>
>>>"Jim Weir" > wrote in message
...
>>>> PLEASE don't do it this way. Remove them the old-fashioned way. Cut that
>>>tube
>>>> off with a saw and I guarantee you chips in the oil pan. Not good.
>>>>
>>>>
>>>> Jim
>>>
>>>Couldn't one push a piece of cloth rolled in a ball down the tube, past
>>>where it is to be cut, and contain the shavings?
>>>
>>>Don't jump me, it is just an idea; wondering if it would work.
>>
>>I'll see if I can find the original instructions, but I think that's
>>how they suggest you do it. If I find the instructions, I'll
>>post back what it says.
>>
>>What I did is use vise grips to collapse the tube near the outer
>>end (where it enters the rocker arm area). The metal is fairly
>>soft, and easy to deform. A small cut-off wheel on a Dremel
>>makes quick work out of cutting the tube in two at about the
>>same location.
>>
>>There are no metal chips scattered anywhere with this method, just
>>a small amount of residual aluminum and abrasive wheel dust
>>associated with the cutting process.
>
>If it is thin enough to bend with visegrips, could you cut it with a
>set of large bolt cutters?

I bet you could. I want to say it's maybe .025 wall, no thicker than
..032, so if you squish it flat, you'd be cutting through maybe an .062
thickness of aluminum.

I might add that it's way easier to remove the original pushrod tubes
and install this kit with the exhaust removed (I had mine off for
rebuild anyway).

Bela P. Havasreti

[Bela P. Havasreti]

On Wed, 17 Nov 2004 23:06:41 -0500, "Morgans"
> wrote:

>
>"Nathan Young" > wrote
>
>>
>> If it is thin enough to bend with visegrips, could you cut it with a
>> set of large bolt cutters?Or, is there enough room to rotate one of those
>little pipe cutters. No residue at all, from that.

No room for a small pipe cutter I'm afraid....

Here's what the instructions say (I don't feel like typing the whole
thing in, so I'll only quote the pertinent part):

"Hacksaw cut the pushrod tube about 2 inches down from the
cylinder head. Remove the piece left in the lifter cover. Now remove
the other piece in the cylinder end by wiggling and pulling towards
the crankcase. Clean and dry the area at the cylinder & case
position".

I would think hacksawing would create at least as much aluminum
"chips" (or dust or whatever) as a cut-off wheel....

FWIW, the only way you'll get a hack saw in there (especially if
you're doing the center cylinders on a 6-cyl Continental) is by
pulling the exhaust.

In any event, I like the idea of stuffing a rag or whatever down the
tube prior to cutting it in half. I also like the idea of using some
bolt cutters after the tube is flattened. I think I'll do it the
latter way next time (when the next pushrod tube starts to leak!).

Bela P. Havasreti

[Ron Natalie]

Morgans wrote:

> Couldn't one push a piece of cloth rolled in a ball down the tube, past
> where it is to be cut, and contain the shavings?
>
> Don't jump me, it is just an idea; wondering if it would work.

Umm...how would you do that? If you could get INSIDE the tube, you
have done all the necessary work to remove it and do it properly.
The "dremel" manouver is to shorten the tube while it is in place.
\

[Bela P. Havasreti]

On Thu, 18 Nov 2004 07:28:36 -0500, Ron Natalie >
wrote:

>Morgans wrote:
>
>> Couldn't one push a piece of cloth rolled in a ball down the tube, past
>> where it is to be cut, and contain the shavings?
>>
>> Don't jump me, it is just an idea; wondering if it would work.
>
>Umm...how would you do that? If you could get INSIDE the tube, you
>have done all the necessary work to remove it and do it properly.
>The "dremel" manouver is to shorten the tube while it is in place.
>\

Take the rocker cover off, pull the rocker arm(s) off, pull the
pushrod(s) out, stuff a piece of rag down into the tube(s) and
cut the tube(s) in half.

Bela P. Havasreti

[Blueskies]

"Bela P. Havasreti" > wrote in message ...
> On Thu, 18 Nov 2004 07:28:36 -0500, Ron Natalie >
> wrote:
>
>>Morgans wrote:
>>
>>> Couldn't one push a piece of cloth rolled in a ball down the tube, past
>>> where it is to be cut, and contain the shavings?
>>>
>>> Don't jump me, it is just an idea; wondering if it would work.
>>
>>Umm...how would you do that? If you could get INSIDE the tube, you
>>have done all the necessary work to remove it and do it properly.
>>The "dremel" manouver is to shorten the tube while it is in place.
>>\
>
> Take the rocker cover off, pull the rocker arm(s) off, pull the
> pushrod(s) out, stuff a piece of rag down into the tube(s) and
> cut the tube(s) in half.
>
> Bela P. Havasreti

Another old trick is to use grease...

[Dan Thomas]

Bela P. Havasreti > wrote in message >...
> On Thu, 18 Nov 2004 07:28:36 -0500, Ron Natalie >
> wrote:
>
> >Morgans wrote:
> >
> >> Couldn't one push a piece of cloth rolled in a ball down the tube, past
> >> where it is to be cut, and contain the shavings?
> >>
> >> Don't jump me, it is just an idea; wondering if it would work.
> >
> >Umm...how would you do that? If you could get INSIDE the tube, you
> >have done all the necessary work to remove it and do it properly.
> >The "dremel" manouver is to shorten the tube while it is in place.
> >\
>
> Take the rocker cover off, pull the rocker arm(s) off, pull the
> pushrod(s) out, stuff a piece of rag down into the tube(s) and
> cut the tube(s) in half.
>
> Bela P. Havasreti

I have sealed the leaks at the outer end of these tubes by removing
only the rocker cover, squirting some strong thinner (like laquer
thinner or brake cleaner) into the joint, and blowing it out with
compressed air. Several applications like this gets all the oil out,
then a wicking-type threadlocker like Loctite 290 will go in there
nicely and harden up after a bit. No more leaks at all. Don't let
Loctite get into anything other than the joint, though.
The inner ends of the tubes may need those boots replaced. The
cylinder base nuts have to come off and the cylinder backed off a bit
to get the boots in, but then the cylinder base seal should be
replaced too and that requires the jug to come right off.

Dan

[Dick]

Exactly the trick I was looking for inside the cover. Thanks.

Thinking to replace those lower pushrod tube spring clips with S.S. hose
clamps.. Thoughts?

Dick

> I have sealed the leaks at the outer end of these tubes by removing
> only the rocker cover, squirting some strong thinner (like laquer
> thinner or brake cleaner) into the joint, and blowing it out with
> compressed air. Several applications like this gets all the oil out,
> then a wicking-type threadlocker like Loctite 290 will go in there
> nicely and harden up after a bit. No more leaks at all. Don't let
> Loctite get into anything other than the joint, though.
> The inner ends of the tubes may need those boots replaced. The
> cylinder base nuts have to come off and the cylinder backed off a bit
> to get the boots in, but then the cylinder base seal should be
> replaced too and that requires the jug to come right off.
>
> Dan

[jls]

"Dick" > wrote in message
. com...
> Exactly the trick I was looking for inside the cover. Thanks.
>
> Thinking to replace those lower pushrod tube spring clips with S.S. hose
> clamps.. Thoughts?
>
> Dick
>
Look at a Continental Engine Manual, Dick. SS Hose clamps won't fit.

Those spring clamps are designed for the purpose and work well in my
experience as long as they are properly seated in the grooves of the
synthetic rubber boots, with one inner clamp compressing the boot on the
crankcase boss tube and one outer clamp compressing the boot on the pushrod
tube. Of course the boots must be properly seated too on the pushrod tube
bosses (also called pushrod housing flanges) and the pushrod tubes. You
have to fight, grunt, and cuss to get them on properly and then use a
telescoping mirror and strong flashlight to assure they are seated properly.
You have to look at them from side to side and bottom to top, because both
the boots and the clamps WILL do their damnedest to come off their seats if
they can. Push from outside inward instead of from inside outward. Hell,
use a heat gun to warm them up a little, but not enough to burn
them.(Sometimes you will bust your knuckles and cuss.) Squirt them with a
good lube like LPS-1 to make the seating easier. An oil leak can be stopped
by rotating or staggering the clamps as long as the boot has not been
ruined. You need a proper pair of spring clamp pliers -- Snap-on or
Craftsman --- to loosen and move the clamps.

This is no work for the faint of heart or pink-fingered. When the clamps
and boots are on right you won't find any oil leaks around them. I have
rebuilt a few engines and have complete faith in them. I just examined two
O-300 engines recently rebuilt and both of them are dry around the pushrod
tubes on both ends. Sometimes you will have leaks around the cylinder base
nuts or cylinder base flanges, but that's something to correct at rebuild
time--- and the subject of another essay with a cussword or two for
mechanics who have damaged the crankcase by slapping the connecting rods
around the cylinder parting bosses.

If you don't have palnuts on those cylinder base nuts, I suggest you put
them on for your safety. The record is full of those nuts coming off,
despite being torqued to specs. And I can tell you that when a jug comes
loose the results are often deadly.