Gearbox external assembly - I'm confused

[Gearbox]

Happy new year all. I have been working in collecting parts to restore my gearbox and trying to piece all the newly obtained missing parts together before starting on rebuilding the gearbox itself. Trials and tribulations of building a car from boxes stored for the 40 years. First of all, I am working on putting together a 1962 Lotus Super Seven with a Cosy 1340cc Pre Crossflow and a 105e gearbox. Despite the PO saying it was a complete gearbox in good condition only missing the Triumph modified shifter, it was more than that. It was missing the gearbox cross mount bracket, gearbox mount, reverse gear shifter fork and rail, remote, and remote adapter. Between contacts in the UK and Dave Bean, I was able to assemble all of the missing bits........ I think.

 

So first issue. I got a used gearbox bracket and was surprised to see that the only thing holding it was rivets to the aluminum floor and tunnel. Needless to say I will be fabricating a brace from the frame to hold it more securely. Dave Bean tells me that my 105e tail housing has a flat land to bolt the rubber mount onto, but they no longer make this mount. But they had an aluminum adapter that bolts onto the tail housing and then you could use a later rubber mount. OK, seems reasonable.

 

But now with all the parts in front of me, I have no clue how it goes all together. The aluminum wedge bolts onto the tail housing, then the rubber mount bolts to the aluminum wedge. But how does the mount fit onto the gearbox cross bracket? There is no hole in the center of the bracket to tighten the rubber mount, nor does the mount fit on to the bracket. It almost seems that the aluminum wedge piece bolted on to the tail housing should just sit in the cross bracket without a rubber mount. But again, no place to bolt it down. What am I missing here? Do I have the parts upside down? Or maybe the wrong parts? Anybody have any ideas? Thanks Allan

[dvl]

Hi Allan,

It looks like you may have the wrong gearbox bracket. On page 72 of Tony Weale's Lotus 7 book, the riveted in gearbox bracket shown has a flat surface with holes to mate with the gearbox mount. Also, my Arch, Lotus style S2/S3 chassis, has a flat mount similar to the picture (with additional structure brazed structure to tie the mount to the steel tubes). I can send pictures if needed.

I hope this helps,

Best Regards,

Dave

[Gearbox]

Thanks Dave, Can you post some pictures and dimensions of the correct bracket. I think I will have to start fabricating a part. Also, what part do I have? I was told it was for an early S2.

 

I found the picture you are referring to, and yes, it looks different than mine. Looks like there is a "C" channel facing down that is flat on top welded between the two wedges, but not sure how the wedges are fabricated (bent) from the pictures. Any help would be greatly appreciated. Thanks Allan

Edited January 7, 2015 by Gearbox

[TheDingo8MyBaby]

My S2 doesn't have the original mount, but here's a better picture.

 

http://i57.tinypic.com/2zpimj9.jpg

 

It's pretty easy to fabricate a bracket. I have a synchro transmission out of an elan that has the block. I used the elan rubber mount and fabricated a flat plate. For the dog-ring transmission without the block (like you have), a $15 Jaguar E-type motor mount (which by the way are the same for sevens) was easily modified to suit and I used a slightly taller bracket.

[Gearbox]

Thanks Dingo, I was going to do the same type of reinforcements in the engine bay and have it continue with 1" Sq. tubing running under both sides of the tunnel with a steel plate for the mount. Not real comfortable with the gearbox mount just riveted on the thin aluminum floor and tunnel sides. So I guess in my case, I would just bolt the rubber mount to the plate with an access hole in the middle to get at the single bolt to tie the gearbox to it. Simple, now all I have to do is figure out how high the mount has to sit and fabricate an aluminum block to elevated it to the correct height.

 

BTW, I noticed that your frame is set up for LHD. Isn't the top diagonal tube from the scuttle to the front be on the other side? I have a RHD and the PO converted over and I'm in the process of going back the other way. Thanks for the info, Allan

[dvl]

Hi Allan,

The set up in my car is nearly identical to Dingo's. I took a few pictures of the mount, but with the transmission in place, they didn't come out particularly well. If you're in the SoCal area, you're welcome to come buy and take measurements of of the trans mount support structure in my car. My car is LHD as well, with the support tube such as a RHD car.

Best regards,

Dave