26 replies to this topic

[Jon9379]

Hi all,

Does anyone know of anyone who has been able to run their engine in reverse?

I have found this link https://www.tradeuni...er-reader-resto
They have done a lot of work to get the engine to run in reverse.

I was thinking about running the engine in standard to keep custom parts down to a minimum.

I have had a few thoughts.

Either no or 2 idlers in the drop gear layout.

Or if there is a way to install a idler between the crown wheel and pinion, so the gearbox still runs in standard but the diff runs backwards.

Any thoughts greatly received.

Thanks

Jon

[nicklouse]

Both engines run the same way.

 

just  like all the rear engined Mini Kit cars.

 

just looked closer at the pictures. Hang on here. They have!

Edited by nicklouse, 12 March 2023 - 08:29 PM.

[Spider]

I'm not sure what you have in mind for your project, however the chap in the linked article reverse ran the rear engine as he turned the while engine gearbox around 180 degrees. That gave him 4 reverse and 1 (slow !) forward gears. To get around that, he modified the rear engine so it would run in the opposite direction.

There would have been no gearbox modifications, though, the thrust washer on the small end of the Laygear would have a short life.

Interesting engineering exercise, but I think there would have been easier ways to achieve his desired outcome.

[Jon9379]

Interesting engineering exercise, but I think there would have been easier ways to achieve his desired outcome.

I intend to have an engine mounted the same as in the link (facing backwards, running forwards, in the rear), as you have said there would be easier ways.

I'm just wondering if anyone has any thoughts that would work better to ultimately get the diff to run in reverse.

Thank you for your comments so far

Edited by Jon9379, 12 March 2023 - 09:50 PM.

[DeadSquare]

An alluminium  BMW K series motorcycle engine has the opposite rotation to a BMC A series, and is only 17mm longer than the A series block.

[Jon9379]

I could be wrong but a few year ago I thought I read something that said when the A series was first developed it was designed as a diesel not petrol and ran the other way.

As I say this was something I read years ago and I could have my wires crossed.

Obviously any work that has been done to the engine including A plus has stuck with petrol fuel since then.

Edited by Jon9379, 14 March 2023 - 06:44 AM.

[Jon9379]

I was thinking how would a chain cope instead of the drop gears? This could remove the idler and get the gearbox to run in reverse while the engine still running forwards.

[imack]

What about the lubrication system? How do you get around the fact the oil pumps running backwards?

[Spider]

What about the lubrication system? How do you get around the fact the oil pumps running backwards?

 

The chap in the video clip mentions this and that he had to modify it but didn't go in to detail.

[DeadSquare]

I was thinking how would a chain cope instead of the drop gears? This could remove the idler and get the gearbox to run in reverse while the engine still running forwards.

 

Looking at things from the flywheel end, the crank rotates anti clockwise, the idler gear clockwise and the first motion shaft anti clockwise.

 

With a chain, the anti clockwise crank will drive the first motion anti clockwise.

[DeadSquare]

What about the lubrication system? How do you get around the fact the oil pumps running backwards?

 

Rotate the pump through 180 degrees and re-drill and tap the holes for the mounting bolts.

 

Ovalise the bottom of the oil ports in the block and fit a thin blanking disk to obscure the top of the ports.

 

Instead of the oil passing under the center-line of the pump, it passes over the center-line as the pump rotates in the opposite direction.

[Jon9379]

Ignore my idea with a chain, I didn't think enough before posting the idea.

My latest bit of thinking is replacing the drop gear idler. A pair of thinner gears, held in a bracket where the original idler sat.

[nicklouse]

I could be wrong but a few year ago I thought I read something that said when the A series was first developed it was designed as a diesel not petrol and ran the other way.

As I say this was something I read years ago and I could have my wires crossed.

Obviously any work that has been done to the engine including A plus has stuck with petrol fuel since then.

That was never done for transverse orientation. the A diesel was put and can still be found in some Tractors and was also modified as a marine units.

[nicklouse]

I was thinking how would a chain cope instead of the drop gears? This could remove the idler and get the gearbox to run in reverse while the engine still running forwards.

Chains have been used in many engines to transfer power from Crank to gear box. The Saab 2.2 engine being one. It used a triplex chain IIRC. Back in the 80s there was talk of a chap in Greenfield that had done a chain drive to replace the Mini Drops. Never found him or any other info. Not sure it was a Mini engine though.

[DeadSquare]

The 1960s Oldsmobile Toronado had a Morse Chain drive from the torque converter to the Auto-box/transaxle, which was tucked under the engine.

 

The sport model produced 400 hp.