How much free play on 365 gearbox

[Sparkrite]

How much free play should the internal gearbox selectors have. Basically once I have selected 1st or 2nd gear on my 365 box, the gear lever can moves sideways much more than in 3rd or 4th. Even when I exclude any wear in the long linkage tubes and check the rotational free play on the gearbox selector output shaft. All the gears work well and can be selected fine, it's just with such a lot of free movement it is not always easy to know when the gear lever is in the right plane before pushing it into gear. Would there be a way to reduce this free play by altering any of the gearbox internals.

[2766R]

This might be a little long winded.  It's a bear of a job but here it goes: My Europa originally was built with a 4 speed 352 transaxle.  Back in the day I fabricated a new cam for the reverse detent.  The new fabricated cam had a less of a ramp angle and a bit longer tang.  I also modified the detent/ball & spring housing.  I'm not exactly sure how the housing was bolted in place but I drilled out the housing for #8-32 capscews.  I counterbored the housing to recess the heads of the screws.  Also fabricated a 1/8" X 1/4" steel bar of suitable length, tapped in two places to line up with the bores in the housing.  I opened up the housing mounting holes in the trans bracket to allow additional movement of the detent housing.  This accomplished two things: (1) Reverse could only be selected by slapping across from the 3/4 gate to force the detent ball into the housing and (2) the housing could be positioned to limit the play in the shift 1/2 gate.

Subsequently a 356 5 speed was installed.  Now a new problem.  No matter how I positioned the detent housing, there would be excessive play in the 1/2 shift gate or the 3/4 shift gate.  I determined that there was too much distance between the reverse and 5th gear tangs on the cam.  My solution was to build up material on one of the tangs.  On removing the cam (which I’ll discuss in a bit) I had a local repair garage deposit some weld, IIRC, on the reverse tang of the cam.  I filed down the weld to approximately .040” (1mm) while also reducing the ramp angle.  I now have approximately ½” (13mm) of free play at the top of the shift lever.

Now about removing the cam!  On the 352 4 speed, it’s a piece of cake.  There is no problem with access.   On the 365 5 speed, it’s quite difficult.   To knock out the split pin, one has to be creative.  First select 5th gear.  Then using an extended 3/16” drill, drill a hole through the trans bracket to allow a pin punch access to the cam split pin (see picture).   Now select neutral.  Using an adjustable wrench on the cam to prevent torqueing the internal mechanisms, remove the elastic stop nut holding the cam to the shaft.  Even though you now have access to the split pin, it cannot be knocked out completely and in fact may have to be bent slightly just to clear the threaded shaft.  Select 5th gear again.  When driving out the split pin, be mindful of the impact forces on the shaft.  Take your time and try to minimize hammering forces.  As usually stated in manuals, to reassemble, reverse the above procedure.

Finally adjust the detent ball & spring housing to achieve equal amount to free play while 1st/2nd or 3rd/4th gears are selected.  Also note that by rotating the detent housing, the way the spring loaded ball has to climb the cam tang changes.  I positioned mine so that reverse can only be selected by slapping across from ¾ gear side of neutral to the reverse gate.  Selecting 2nd from 3rd is now worry free!  Hope this helps.  YMMV

I’ve included a few pictures and a video that I hope adds clarity.

P.S. I’ve actually wondered why this hasn’t come up more often.
Gerry (2766R)

https://youtu.be/aB04yMnPQ80

[dakazman]

  I noticed the same problem with the 336, FWIW here is what I came up with but haven't tested yet.
   https://www.lotuseuropa.org/LotusForum/index.php?topic=2058.2310
  It eliminated alot of the slop out .
Dakazman

[Sparkrite]

This might be a little long winded.  It's a bear of a job but here it goes: My Europa originally was built with a 4 speed 352 transaxle.  Back in the day I fabricated a new cam for the reverse detent.  The new fabricated cam had a less of a ramp angle and a bit longer tang.  I also modified the detent/ball & spring housing.  I'm not exactly sure how the housing was bolted in place but I drilled out the housing for #8-32 capscews.  I counterbored the housing to recess the heads of the screws.  Also fabricated a 1/8" X 1/4" steel bar of suitable length, tapped in two places to line up with the bores in the housing.  I opened up the housing mounting holes in the trans bracket to allow additional movement of the detent housing.  This accomplished two things: (1) Reverse could only be selected by slapping across from the 3/4 gate to force the detent ball into the housing and (2) the housing could be positioned to limit the play in the shift 1/2 gate.

Subsequently a 356 5 speed was installed.  Now a new problem.  No matter how I positioned the detent housing, there would be excessive play in the 1/2 shift gate or the 3/4 shift gate.  I determined that there was too much distance between the reverse and 5th gear tangs on the cam.  My solution was to build up material on one of the tangs.  On removing the cam (which I’ll discuss in a bit) I had a local repair garage deposit some weld, IIRC, on the reverse tang of the cam.  I filed down the weld to approximately .040” (1mm) while also reducing the ramp angle.  I now have approximately ½” (13mm) of free play at the top of the shift lever.

Now about removing the cam!  On the 352 4 speed, it’s a piece of cake.  There is no problem with access.   On the 365 5 speed, it’s quite difficult.   To knock out the split pin, one has to be creative.  First select 5th gear.  Then using an extended 3/16” drill, drill a hole through the trans bracket to allow a pin punch access to the cam split pin (see picture).   Now select neutral.  Using an adjustable wrench on the cam to prevent torqueing the internal mechanisms, remove the elastic stop nut holding the cam to the shaft.  Even though you now have access to the split pin, it cannot be knocked out completely and in fact may have to be bent slightly just to clear the threaded shaft.  Select 5th gear again.  When driving out the split pin, be mindful of the impact forces on the shaft.  Take your time and try to minimize hammering forces.  As usually stated in manuals, to reassemble, reverse the above procedure.

Finally adjust the detent ball & spring housing to achieve equal amount to free play while 1st/2nd or 3rd/4th gears are selected.  Also note that by rotating the detent housing, the way the spring loaded ball has to climb the cam tang changes.  I positioned mine so that reverse can only be selected by slapping across from ¾ gear side of neutral to the reverse gate.  Selecting 2nd from 3rd is now worry free!  Hope this helps.  YMMV

I’ve included a few pictures and a video that I hope adds clarity.

P.S. I’ve actually wondered why this hasn’t come up more often.
Gerry (2766R)

https://youtu.be/aB04yMnPQ80

Thank you so much for the reply and particularly the YouTube clip. I have now filmed mine from the same position and unscientifically it seems to have about 2 or three times as much free play as yours.
I am still trying to re read your post to make sure I fully understand it,
But from what I can see in your clip,once a gear is selected the two prong cam has no bearing on the amount of free play,and so it must be inside the gearbox.

[2766R]

"But from what I can see in your clip,once a gear is selected the two prong cam has no bearing on the amount of free play,and so it must be inside the gearbox."

Oh but the tangs on the cam absolutely determine the amount of free play.  One way to prove this is to remove the ball/spring housing temporarily.  Then select 1st/2nd and/or 3rd/4th gear.  There will be a significant amount of free play.  Alternately, you can apply a layer of JB Weld to the face of one of the tangs (degrease first with solvent ie: Brakleen).  It won't last long but will prove that by adding a permanent weld will yield less free play.  Like I mentioned before, it will require carefully removing the thickness of the weld to achieve some free play.  Again, I hope this helps.

Gerry (2766R)     

[jbcollier]

The stock Renault 365 transaxle does not use an external detent system.  That is a Lotus addition and quite why they did it, I don't know.  Some people remove the Lotus addition and refit the stock Renault detents and find better shift action.  Doing this does require the fabrication of a reverse lock-out.

As the stock Renault 365 is not known for sloppy gear selection, I would say something is worn inside.  The most likely candidate is the "rocking lever" which wears the bore in the rear case.  It can be repaired by sleeving its bore.

[Sparkrite]

As Gerry suggested, I have temporarily soldered on a small flat piece of steel on the inner faces of both the tangs and this has greatly improved the free play. Once I can confirm it still functions well with a test drive, I will weld up the tang faces and file to suit.
But so far I am very happy with the result.