Can you determine if a Lotus 5-speed gearbox is good without first installing it?

[BrianK 106]

I bought my car knowing that it has bad 2nd and 3rd gear synchros, BUT it came with a spare gearbox.

When I bought it, the seller said that the spare was a "good" gearbox, but when I pressed him (after buying the car), he said that he didn't really know the condition of it.  In fact, he had inherited the car, and the real previous owner is now deceased; so there's really no telling.

With that... is there some way to determine if the gearbox is good before installing it?  

While I'm asking - any tips on replacing the gearbox? Does the engine have to come all the way out of the engine bay, or can I just scoot it forward a few inches while it hangs off the engine hoist?

[gusexige 2]

I have not rebuilt a 5 speed, but have done a ford 4 speed

Not really that complex. 

Pull the cover off and look at the dogs and synchros. Each gear has little doghouse shaped 'dogs' that the peak of the roof if you will gets rounded. Each synchro has the same that mate with the shifter hub. These start getting rounded day one, but if they stop looking like doghouse roofs and start looking like igloos: dead

 

 

mainshaft bearings don't usually die. 

countershaft bearings do. 

 

Anyway, take the cover off and loo at what is going on. 

 

[mikeeech 349]

The engine has to come out to get the gearbox out unfortunately. No telescopic propensity on these.

[black eclat 59]

Drain the oil and inspect for metal "fines". Use a magnet to be sure.

[gusexige 2]

I think he is saying that he has one out of the car. 

Popping the lid and taking some pics of what can be seen close up in focus would allow some speculation on condition

 

Generally the 2nd gear synchro is the most worn[since it is used more and frequently harder]

[BrianK 106]

The answer was pretty obvious when I finally dug the transmission out of storage and opened the case.

Anyone need a paperweight?   

I think it's time for a W58. I believe Lotus Bits and Conversion Components are my sources for conversion kits, yes?  Any other options?

Edited October 20, 2020 by BrianK

[TAR 418]

SJ Sportscars still list quite a few parts for the 5 speed gearbox. You may be able to repair it.

🙂

[The Nut 29]

I'm sure that would polish up. Better to find out now that later.

Regards to all

John

[lil503 19]

Go for a getrag or ford type 5 gearbox Brian,the lotus box is fragile to say the least,ive had my elite 12 years now,use it most days weather permiting and done four gearboxes all of them gave no prior warning ie rattles or whining just went bang locking the back wheels i put in a type 5 4 speed in 3 years ago mated to a 912 engine although a 5th gear would be nice the box has proved to be strong and reliable

[eclat22 115]

I would 2nd the Getrag, it's the only thing I haven't broken on the Eclat race car

[BrianK 106]

Interesting (and valuable) to hear that you prefer the Getrag. I’ve read that the w58 gear ratios are more suited for our car, but have heard no first-hand experience. 
 

What did you use for a bell housing? The Lotus unit? I fear that (The Lotus bell housing) will be near impossible to find in the US... I believe Lotus stopped importing the Elite/Eclat/Excel before the switch to Getrag.

[eclat22 115]

The race car is an S2 so came with the Getrag from the factory and I assume a Lotus Getrag specific bell housing. I like the Getrag but have to admit to not having driven a car with the Lotus Maxi box. With the right gear oil in it it is slick and nice to use, and well used when being raced.there appears to be similar Getrag boxes in certain Jags of the same era that could potentially be used but you would still need the bell housing or possibly and adapter making. Possibly Lotusbits might have the parts but I doubt it would be cheap and then there would be the shipping.

Sorry I can't help more

Dan