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Hello everyone,

I just bought a 1973 Lotus Europa Special (European model) and I'm trying to figure out the best oil to use in the engine and gearbox. Manual suggests everything from 20w20 to 20w50 depending on the climate. Is it ok to use redline 10w40 fully synthetic in the engine and redline mt-90 in the gearbox in summer use?

Another issue I'm having is a leak from both driveshafts. What size are driveshaft/output shaft seals and the o-rings? Is 36x54x7mm the correct size?

Also what is the correct size of the sump plug washer?

Thank you!
 

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Hello everyone,

I just bought a 1973 Lotus Europa Special (European model) and I'm trying to figure out the best oil to use in the engine and gearbox. Manual suggests everything from 20w20 to 20w50 depending on the climate. Is it ok to use redline 10w40 fully synthetic in the engine and redline mt-90 in the gearbox in summer use?

Another issue I'm having is a leak from both driveshafts. What size are driveshaft/output shaft seals and the o-rings? Is 36x54x7mm the correct size?

Also what is the correct size of the sump plug washer?

Thank you!
Hi and welcome. I have a federal 1974 Special.

You need to join Lotus Europa Community, a forum exclusive to Europa, and Lotus Europa Central which has an EXTENSIVE knowledge base that likely will answer all your questions.

You need a shop manual for your car.

Re the oil. A lot of argument on this. Original spec was 20w50 Castrol. That was 40 years ago. If you are using your car lightly, most folks say using the original spec mineral oil is just fine. If you're putting a lot of miles on your car, or stressing it at the track, to go with the synthetic.

JOIN those groups, and the is a Lotus Europa Yahoo group that is very helpful as well.
 

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Ditto on the Knowledgebase for gearbox oil recommendations. For output shaft seals and O rings, I've always ordered from the usual Lotus vendors, it was so much easier than measuring and sourcing the parts yourself. When you replace your seals, I would highly recommend researching the topic of shimming the output shafts in the Knowledgebase. Welcome to Europa ownership, you'll find an active and helpful group of Europa owners on the Yahoo mail list and Lotus Europa.org.

JT
 

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There has been a lot of discussion recently about the difference between the old oils and the current oils. The old "flat tappet" engines are said to require extra lubricity agents such as zinc and phosphorus that are not found in many modern oils because they foul the oxygen sensor of modern engines. If you google 'flat tappet oil' there are many articles with good information. I've couched my comments here because I have heard some say that this problem is a hoax. I'm not sure it is but I'm not an oil engineer. I would err on the side of caution.

I asked Redline about this and this was their answer:

Thank you for contacting Red Line Oil, our Motor Oils contain good levels of ZDDP offering substantial protection for your BDA cams and lifters. In your engine the 10W40 would be a good all around choice, especially if internal clearances are set up a little loose. Most of our Motor Oils contain 1200 ppm phosphorus, phosphorus with sulphur providing the critical anti-wear protection for flat tappet style cams and lifters/followers.

A typical oil of the day in the mid 70’s and earlier would have contained about 800 ppm phosphorus, increasing to to a high of between 1000 and 1100 ppm from the late 70’s to mid 80’s.
As for the proper oil for the transaxle, Red Line recommended their 75W90NS. I have found that Red Line makes a real difference in the way it shifts. I had a slight roughness between 1 and 2 with Castrol synthetic gear oil (don't remember the type or weight) and Red Line fixed it. It's pretty good stuff.
 

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73 Europa oil?

Hello everyone,

I just bought a 1973 Lotus Europa Special (European model) and I'm trying to figure out the best oil to use in the engine and gearbox. Manual suggests everything from 20w20 to 20w50 depending on the climate. Is it ok to use redline 10w40 fully synthetic in the engine and redline mt-90 in the gearbox in summer use?

Another issue I'm having is a leak from both driveshafts. What size are driveshaft/output shaft seals and the o-rings? Is 36x54x7mm the correct size?

Also what is the correct size of the sump plug washer?

Thank you!
Whatever you do stick with conventional oil, NOT SYNTHETIC or you will have more oil leaks as the seals can not handle it.I know because my car was stored before I bought it with Castrol Syn.And after driving it about a year they started leaking. Castrol is great oil or syntec but dont use it or any syntec oil. If you replace the seals with the newer seals then you might get away with the syntec , the older seals that are in my car were original from what I was told:no:
 

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Oh yes, +1 for non-synthetic if your car hasn't been converted yet. The Castrol Syntec does an amazing job of keeping the inside of your engine residue free (I can show you pictures of the top of my head after 175k miles). But because they clean everything right off, they cause lots of oil leaks in older cars, this is not a myth.

My roommates Alfa GTV6 spews oil from every possible seal and he can't get it to stop now :( It was ok before but now he needs to pull the engine and start over with fresh o-rings and seals everywhere!

Even the newer non-synthetic oils contain detergents that will keep your engine clean for normal use. I'd go 10W-40 non-synthetic (Redline certainly wont hurt...).

75W-90 for transmissions is a little heavy but does work very well for differentials. I have 75W-90 non-synthetic in my 1978 Datsun 280Z transmission, and it shifts awesome when warm, but a bit sluggish when it is cold. Many manual transmissions/transaxles use regular 30W motor oil nowadays. I had good luck changing from 30W to 40W in my one car. I am not familiar enough with the Renault box, but I would go with 30W because it is a good safe number and under normal conditions you won't overheat it in these little boxes. I can check my TCS service manual to see what they suggested 40 years ago and report back if you would like.
 

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i rebuilt my 72 TC and used syntec after the break in...never leaked oil
 

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I checked my TCS manual last night. They suggested lots of oils that I have never heard of, but for operation above 0°C, they recommend 10W50 or 20W50 Mobile or Shell. So I would say if your engine hasn't been rebuilt in recent history and it still runs strong, go with 10W50 non-synthetic.

On a different note, I noticed the manual also says run 16psi front air pressure, 26 rear pressure. That is REALLY low!
 

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I've been putting syntec in my TC for several years without a problem. If anything, it doesn't drip as much as it used to.

And I quit following the factory tire pressure recommendation a long, long time ago. After a bit of experimenting I found that my own preference is to run the tires at F:25 and R:30. Others' experience may vary.
 
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