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McDesign
McDesign New Reader
1/17/20 4:06 p.m.

I have a Kelmark-style conversion with a Corvair 4-speed.  This means the trans is flipped around, and the ring gear is running "backwards".  Kelmark supplied a new top cover with a ramp that supposedly drips oil onto the gear interface - I'd like to do better.

I'm thinking I'll add a differential oil pump from a circle track car, picking up from the lowest spot (on the tranny), and squirting on the pinion/ring interface.  Has anyone done that?  Looking for ideas before I start.

Got it out and apart now for resealing; easy to drill and tap and add AN fittings.

Thanks

californiamilleghia
californiamilleghia Dork
1/17/20 4:12 p.m.

I like the idea ,  does a circle track car use regular 90 weight gear oil ?

and does the Corvair trans share the gear oil with the gear cluster ?

McDesign
McDesign New Reader
1/17/20 4:16 p.m.
AngryCorvair
AngryCorvair MegaDork
1/17/20 4:19 p.m.
McDesign said:

I have a Kelmark-style conversion with a Corvair 4-speed.  This means the trans is flipped over, and the ring gear is running "backwards".  Kelmark supplies a now-top cover with a ramp that supposedly drips oil onto the gear interface - I'd like to do better.

I'm thinking I'll add a differential oil pump from a circle track car, picking up from the lowest spot (on the tranny), and squirting on the pinion/ring interface.  Has anyone done that?  Looking for ideas before I start.

 

hit up David Clemens at Stinger Motorsports in Roanoke VA, email stingermotorsports@cox.net .  I'm pretty sure he does something like this on his track cars, or perhaps has done it for customers.  Either way, you are not breaking new ground here.

McDesign
McDesign New Reader
1/17/20 4:26 p.m.

Super - just emailed him.

Thanks

AngryCorvair
AngryCorvair MegaDork
1/17/20 4:49 p.m.

David is a great guy, and knows corvairs in all forms.  i got MONZORA from David.  see more at MONZORA redux...

iceracer
iceracer UltimaDork
1/17/20 5:39 p.m.

Does flipping put the ring gear out of the oil "sump" ?

McDesign
McDesign New Reader
1/17/20 7:36 p.m.

Sorry - I was wrong - trans is rotated 180 degrees about a vertical axis - not flipped over.  Left is right, etc, but top is still top.  Kelmark saw lube as an issue, so made the "ramp" in the pic -

Forrest

McDesign
McDesign New Reader
1/17/20 7:44 p.m.
Hey, looking at the thing, there are really two sumps, trans and diff, separated by the higher join.
Maybe pull from both to help mix, or is there some benefit to keeping the two types of gear/synchro debris somewhat separate?
 
Anyone got an opinion?  I'm stoked to finally get on this forum - seems like lots of participation!
 

Forrest

californiamilleghia
californiamilleghia Dork
1/17/20 7:52 p.m.

Corvair motors run backwards , 

So a corvair transaxle used as a mid engine box  turns the correct way for most engines , 

Fiat 850 motors also runs backwards........

McDesign
McDesign New Reader
1/17/20 8:58 p.m.

I've just added 6AN bungs to both of the "sumps" - tranny and diff.

Forrest

McDesign
McDesign New Reader
1/17/20 10:08 p.m.

I removed the first "E" and added the 6AN bung here - right above the R&P mesh.

Forrest

aircooled
aircooled MegaDork
1/17/20 11:39 p.m.

I can tell you after messing with my T5 conversion (normal Corvair diff mated to T5 trans), I needed to seal off the diff from the trans so I don't have to run gear oil in the trans (it likes Syncromesh).  There is a hole in the diff between the trans, that is lined up with the ring gear. It's function appears to be to catch gear oil flung off the ring gear.  I assumed this was to oil the bearing that is exposed between the two, but that is not needed because that bearing sits below the oil level of the diff.  I think it's primary purpose is to allow the diff to slowly pump oil into the trans, which eventually flows back. You can see the trans holes in your pic.

Probably not a big deal but the Kelmark setup will clearly not fling oil that way and will stop the circulation of gear oil.

Of note, the location of your drain, I am sure you will use a 90 deg adaptor but that spot is a low spot.  I use the Crown lower arm bracket (should be redrilled to stock geometry of course) and it serves as a nice skid pad to protect my Clark's style oil pan.  Something to look out for.

BTW: cutting the Crown bracket in half (and welding it up to add strength) makes it much easier to install the arms.

McDesign
McDesign New Reader
1/18/20 8:09 a.m.

Yes - I had previously lowered my inboard pickup points about an inch and a half to decrease camber change, so my right-angle bung will be slightly higher than that - here are some poor pix of when I did that - modified and unmodified.

Forrest

frenchyd
frenchyd PowerDork
1/18/20 9:51 a.m.

In reply to McDesign :

There are simple ways and hard ways to do things.  You seem intent on doing it the hard way.  
Here's the simple way. 
climbing gear lube. Yes,  they make it for us quick change rear end guys.  
second if you are pushing the transmission hard ( as in racing)  you might use a pump to cool the oil.  Common trick of us poor boys is to use an electric fuel pump but wait until the oil temp exceeds 200 degrees before turning it on!!  Less than that you don't need to cool the oil and a fuel pump won't pump gear lube that cold.  
 

aircooled
aircooled MegaDork
1/18/20 10:00 a.m.

OK, yeah, looks like that linkage already takes up some of that space.

californiamilleghia
californiamilleghia Dork
1/18/20 10:05 a.m.
frenchyd said:

In reply to McDesign :

There are simple ways and hard ways to do things.  You seem intent on doing it the hard way.  
Here's the simple way. 
climbing gear lube. Yes,  they make it for us quick change rear end guys.  
second if you are pushing the transmission hard ( as in racing)  you might use a pump to cool the oil.  Common trick of us poor boys is to use an electric fuel pump but wait until the oil temp exceeds 200 degrees before turning it on!!  Less than that you don't need to cool the oil and a fuel pump won't pump gear lube that cold.  
 

what is climbing gear lube ?

and great idea on the 200 degree fuel pump  idea , what brand of pump can take that much heat ?

Thanks for the info

McDesign
McDesign New Reader
1/18/20 10:21 a.m.
frenchyd said:

In reply to McDesign :

There are simple ways and hard ways to do things.  You seem intent on doing it the hard way.  
 

Yes - I am a mechanical engineer and a dilettante - but I have that luxury. 

This is a play car, and it's fun to make it "best"; a retreat from the corporate world.  In this case, I'm going to use an old Town & Country PS pump for the pump - just to see if it works, and because I have one.

I have plenty of other cars to daily drive, and a CL600 for pretty days.

 

Forrest in Atlanta

frenchyd
frenchyd PowerDork
1/18/20 11:00 a.m.

In reply to californiamilleghia :

I always used Holley pumps. Never seemed to cause a problem unless I accidentally started it with fluid cold. Usually I'd blow the fuse but sometimes it was new( used) pump time. ( I'm a big fan of race car swap meets ). 

Vigo
Vigo MegaDork
1/18/20 2:18 p.m.

I'm a bit late to the party to be saying this but i think you should watch this series:

Differential cover testing

 

McDesign
McDesign New Reader
1/18/20 10:26 p.m.

In reply to aircooled :

Hey - got the sumps connected - one side of one "T" will be a drain; the other side of the other "T" will be the suction side of the pump.

And this was fun - I decided to drive a PS pump off of the output of the left half-shaft flange.

In my stash, found a really old V-belt pulley made from two sheets of steel (from my grandad, so maybe 50-60 years old), rolled and spot-welded around the perimeter.  I cut out the center, and then aligned and tacked the U-joint caps to the pulley - cool!

Finished up and trued and continuously welded - axial and circumferential runout is good -

Forrest

ChasH
ChasH Reader
1/18/20 11:46 p.m.

Are there issues with driving the ring and pinion gear set on the "coast" side rather than the "drive" side? The gear  teeth have a different pressure angles coast / drive with the coast side being less efficient and placing greater loads on the differential side bearings.

Someone mentioned gear lube earlier. I believe the Corvair has a spiral bevel gear final drive rather than a hypoid gear requiring GL4 oil which is OK with synchronizers. A cooler is a good idea in any case.

McDesign
McDesign New Reader
1/19/20 8:14 a.m.

I think that is a concern, hence the desire to get some more lube on the mesh point.  As "play" cars, these aren't driven a lot - and gears are cheap at Clark's Corvair.

But - what I've just spent a year doing is stretching the wheelbase 10" within the body (moving the wheel arches back).  I'll fuly develop this drivetrain, but it's made to entirely cut, off as a unit, behind the seats. 

I'm designing and building a complete new rear chassis and stronger drivetrain with a '70s design, but not the normal Eldorado/Toronado "mount the engine over the axle" setup, but using the Eldo trans, but not the diff - got a better plan to put it all in front of the rear axle - hence the need for ten more inches of wheelbase.

Yellow was the initial concept; red is what I went with - I've already built the 'cage and rear bulkhead.  Engines and Eldo trans I have - Caddy 500 offset-ground crank to use BBC rods, so 565 cubic inches.  Short driveshaft going to offset QC rear with a flipped ring gear; four link with a Watts linkage.

Forrest

 

Stampie
Stampie UltimaDork
1/19/20 8:18 a.m.

In reply to McDesign :

I approve of Caddy big block. 

McDesign
McDesign New Reader
1/19/20 8:26 a.m.

Yes - with the FE Ford tunnel ram and adapter, it's majextically massive -

Forrest

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