Author Topic: 365 Gearbox leaks and other woes.....  (Read 528 times)

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Offline TCs Euro

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365 Gearbox leaks and other woes.....
« on: Friday,October 18, 2024, 01:45:26 PM »
Hi All.

I have a 365 gear box in my TC with a few issues. I am fairly new to the car, had it for a year or two but only done a few hundred miles in it. I've had other cars to work on...play with.. It engages into gear just fine.

 It has some leaks around the drive shaft seals.
 Feels tight to turn the wheels when on a ramp. Is this the shim tensioning....?
Is not particularly quick.... feels like it is being restricted, like having a sticky brake caliper.
Engine runs a little on the hot side.

Your thoughts and input would be appreciated....
 
Many thanks and kind regards,
Jay
'73 Twin Cam Special, Midnight Blue, 2nd owner, 129K Miles...

Offline EuropaTC

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Re: 365 Gearbox leaks and other woes.....
« Reply #1 on: Friday,October 18, 2024, 10:34:43 PM »
Hi Jay,

Oil leaks ?  it's a Lotus....

Ok, being serious minor leaks are common. Mine's a 352 box and when driven daily always had indications but not usually bad enough to form a drip under the car. After not using it for a few years I changed the oil and came back to find a pool underneath the car so had to change the seals. It's easy on a 352, not sure about the 365 but if it's a bad leak that does sound like a winter project.

Shim tensioning is mainly about stopping the in/out play between the driveshaft and gearbox, it shouldn't affect drag on the wheel itself (or at least it doesn't seem to on my car).

If your car is standard my first guess would be the rear drum brakes. It could either be because the handbrake cable is binding and partially holding the shoes against the drum, or simply that they've been adjusted too tightly with the shoes dragging. With an under dash handbrake going through a front lever then a horseshow splitter in the centre tunnel, it's got to be absolutely spot on to work well. So over-tight shoes is one way of getting an MoT pass mark - assuming the tester turns a blind eye to it !

The TCS should feel nippy although it's not fast compared with current sports cars such as the Elise/Evora/Porsche/etc.  Even if you discount the period road tests as being fixed by Lotus with "special" engines, the cars should still be doing 7-8 seconds for 0-60 and feel good compared with most modern traffic. 

When you say it's running hot, what numbers are you getting on the dial ?

Brian

(edited because I couldn't believe the number of typos I made first time around !)
« Last Edit: Saturday,October 19, 2024, 12:34:04 AM by EuropaTC »

Offline 4129R

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Re: 365 Gearbox leaks and other woes.....
« Reply #2 on: Saturday,October 19, 2024, 12:02:35 AM »
If the engine is running hot, first take out the thermostat, stick it in a pan of very hot water, heat the water, and see if it opens at 90'C, just before boiling.

Then fill the cooling system through the large hole in the cylinder head where the thermostat is located before replacing the thermostat and tightening the two 5/16" UNC bolts.

Offline TCs Euro

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Re: 365 Gearbox leaks and other woes.....
« Reply #3 on: Saturday,October 19, 2024, 05:09:02 AM »
Thanks for your replies gents.

Engine temp is over 90, so have the heater and fan on permanently, I have changed the thermostat for new, same reading.

It has a Spider chassis so discs all round. I don't think the brakes are sticking as when you drive it the disks don't feel hot....

My gut feeling says something gearbox wise.... further investigation required I think.
'73 Twin Cam Special, Midnight Blue, 2nd owner, 129K Miles...

Offline 4129R

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Re: 365 Gearbox leaks and other woes.....
« Reply #4 on: Saturday,October 19, 2024, 06:59:57 AM »
Thanks for your replies gents.

Engine temp is over 90

Sometimes either the sender in the cylinder head, or the gauge itself, or the voltage stabiliser, gives the wrong reading. I have had to replace all three to get an accurate reading.

Offline TCs Euro

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Re: 365 Gearbox leaks and other woes.....
« Reply #5 on: Saturday,October 19, 2024, 12:47:42 PM »
But the fan is kicking in too with the rad temp switch.... so temp is possibly getting high, but as you say could be defective sensors..

Thanks again for your input.
'73 Twin Cam Special, Midnight Blue, 2nd owner, 129K Miles...

Offline EuropaTC

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Re: 365 Gearbox leaks and other woes.....
« Reply #6 on: Saturday,October 19, 2024, 10:57:42 PM »
Hi again,

90C is hotter than normal, at least for my car.  I'd say mine is running 80-85-ish although it's hard to get an exact number given the markings on the dials.

Sensors. voltage supply and instrument accuracy are the usual suspects and as they've already been debated I'll throw a few wilder ideas into the check list;

1. Water pump belt ? You don't need a lot of tension on the belt to spin the pump but it does have a longer circulation path than a conventional car so if it's old and slipping, that would be worth checking.

2. Along with the comment that the car doesn't feel as spritely as it should, is the ignition timing right ? If it was retarded prior to your ownership then that could account for the performance and also hotter running ? I do remember the classic magazines going on about retarding ignition when 5 & 4star fuels started to disappear although I've never bothered and they seem to run ok to me. 

Brian