365 Gearbox Issues

[Rosco5000]

 Hi Everyone,
I am hoping for some help with an issue I am having with my freshly rebuilt 365 transaxle.

I have a 1974 Europa Twin Cam, that I have been rebuilding the engine and transaxle.  My other thread has some progress posts.

I have reached the point of test driving the car.  On my first short test drive everything was good for a first run.  No issues, just some tuning for smoothing out the driving and power delivery, no biggie.

The second drive had me driving around for 20-30 miles and after the transaxle oil got to temperature 3rd gear started grinding on every up shift and down shift unless I double declutched.   This was similar to the problem before the rebuild, but was happening in 2nd and 3rd gear.  At this point 2nd is fine.   The transaxle had every bearing, synchro and seal replaced.  I double checked synchro to hub clearances and saw no issue with 3rd gear.

I am running Red Line oil 75W90 oil GL-5.  I am thinking maybe my oil is wrong.  My first thought is to try Red Line MTL but if I have to I will pull the transaxle again and try to figure out what is wrong, my big worry is I can see how anything else is bad unless the hub itself is bad.

If anyone has any suggestions on the route to take I am all ears.  I just want this driveline to worry free for some fun driving. 

Cheers,
Ross

[BDA]

I don't think it's the oil. I've talked with the Red Line folks about the proper oil. I was asking about my NG3 but the 365 is similar. Because the pinion is not very offset from the crown gear, you have a lot of flexibility in oils. Here is what they said:

Thank you for contacting Red Line Oil, in your Lotus/Renault transaxle the 75W90NS would be recommended as they call for a GL-5 gear oil.

Obviously they don’t require a GL-5 gear oil as they don’t use a high offset ring and pinion and the included owners manual lists a MIL-L-2105B as being suitable, a GL-4 gear oil. Based on that and the viscosity called for, one of our GL-4 gear oils would be suitable such as the MT-85, likely providing similar viscosity at operating temperature to the original 80W. 

Have you checked your linkage?

Speaking for myself, I had some troubles upshifting to 2nd sometimes because for whatever reason it did not feel like 2 was straight below 1 but a little to the left but I think in reality, that sensation is from seating position or the way I had my arm. I've just learned to put slight pressure to the left going from 1 to 2. I wonder if a similar thing might be an issue for you.

Lastly, if your clutch is out of adjustment, it can make it hard to get into gear (but usually, that affects all your gears).

[4129R]

Is your problem actually changing gear, or noise when driving in that gear?

Gear changes can be difficult if the clutch pressure plate is worn.

My gearchange was transformed with a new pressure and driven plate.

[jbcollier]

+1 make sure the clutch is fully releasing before stripping the transaxle.

If you do end up stripping the transaxle then test each sychro on its gear.  Push and twist the synchro on.  It should lock in place and not bottom out.

[Rosco5000]

Thanks everyone for the response.  I will check the linkage first as I thought it a bit hard to find 1st when stopped so that is a good point I didn't think about.  I have had absolutely no issues with other gears so to me on first thought that rules out the clutch but I will check its adjustment tonight as well.

It was funny as after the first 10 miles of driving it was on every shift...

Double and triple checking everything outside the transaxle tonight.
Cheers,
Ross