Air tool oil for me. My portable AFR gauge says it is about right too for my combination.

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"In two years time your car will be like a lady's clothes, out of date, my car will still be in fashion when I am dead" - Sir Alec speaking to Pininfarina

SU's handbook says its SAE 30.... but observation suggests it doesn't matter much.. Look at the range of stuff people find works for them..

Kev's suggestion of "nothing" is interesting. I can always tell if I've been fiddling with the carbs and forget to replace the oil. Car runs fine but is a B&^*er to start.....

Cheers, Ian

I have found that you have to experiment to find the right oil for your carbs.
My S has 1.5 twins and likes 0-40; mini K has1.25 twins and likes 15-50; and like Drmini, it is happy without oil at all!
Totally disagree with the site referred to by Morbo28 about filling to 1/2 inch BELOW piston rod; I did that for 25 years until a friend said to fill to 1/2 inch ABOVE piston rod. Cars now run happily all the time. Oil will drain away over a week or so and needs topping up regularly.
You don't have that problem with fuel injection!

mine drains away, but I didn't bother topping it up again... so I guess I'm not using anything

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did I tell you that I won a trophy?

Mine was always a bugger to start when cold, damper oil or no oil.
So is miniDave's rally car, so he is now fitting a Weber .

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I've used auto trans fluid in most of my Minis, with exception of my 1100 van. It ran best on 20w50.

I don't think there is a correct answer for what oil to run in SU dampers. Run what works best for that engine.

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SAE30 engine oil....
the correct ounce weight spring however makes the difference.

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....you just lost him his insurance bonus!

997

+1. Sort this out first before playing with dashpot oil.

The best method I have found is to have a bore scope pointed down the throat of the carb and then go for a run (my borescope is a USB one and I record the run on my laptop). Don't believe what people / computer programs tell you you need.

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"In two years time your car will be like a lady's clothes, out of date, my car will still be in fashion when I am dead" - Sir Alec speaking to Pininfarina

I keep meaning to do that... I bought one of these, but so-far it's only been used for deep nasal and ear hole investigations (ewww!)

http://www.banggood.com/A99-2IN1-720P-2 ... 46380.html

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did I tell you that I won a trophy?

It is very useful Simon. I have been helping Tadhg with mine. He has a 1310, big cam, race headers, AEG163 head etc etc etc but with a pair of HS2s. Multiple people told him yellow springs, WinSU told him yellow springs but when I put the borescope down the carbs the yellow springs were only letting the dashpots raise approx 5mm at WOT/redline. After swapping around springs, it actually needed blue springs. The process of finding what damper oil to use and what needles had to start all over again.

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"In two years time your car will be like a lady's clothes, out of date, my car will still be in fashion when I am dead" - Sir Alec speaking to Pininfarina

How often should dashpot oil be replaced

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It certainly sounds as if the answer varies from person to person. Everything from no oil through to 50 weight!

1018cc, what should I look out for if I use the bore scope when the engine is running?

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Build thread for Supercharged 1275 1967 Deluxe Resto
Build thread for Mini ute conversion 998cc Turbo

Lots of people use ATF, I buy SAE30 mower oil. Its available anywhere. one day ill buy some proper SU SAE20! I've found light oils to create a hestitation on acceleration.

You want the damper to be open pretty much all the way at peak horsepower. If you don't know where peak horsepower is, I usually just work towards being fully open at redline. I usually check to see that it is using the entire length of the needle.

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"In two years time your car will be like a lady's clothes, out of date, my car will still be in fashion when I am dead" - Sir Alec speaking to Pininfarina

I usually take the whole carby piston assembly out and clean with carby / throttle body cleaner every engine oil change or two. The damper oil gets changed at the same time, obviously.

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