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SU's and oil

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OK, so I will be installing my L28 AGAIN at some point this week. It's been a few moons since I have messed with a set of these carbs. I did just have a motor in the car and the carbs are acting fine asfar as I could tell. But, one thing I would like too get done is the oil in the carbs.

How do you go about checking the the oil level? Also if I recall correct I am thinking it's 20w oil. Am I wrong?

One other thing on this. How do you go about doing a oil change on the SUs ?

Funny, but you should have seen the looks on the faces of the guys at our shop when I said I think I need too check the carb oil LMAO LOL

Thank you.

I think most everyone uses ATF. Just pop the black cap on the top and pour it in. Be careful no to overfill, as excess fluid will spill down into the carb under operation and be burned in the engine. Not a big deal though.

I think this is all correct, haven't messed with mine since I bought it a year ago. But it's on my list for next week actually.

Edited by JonnyRock

ATF is wrong, it averages about SAE 5, whereas specs call for SAE 20. I (and many others) use motorcycle fork oil. That's about the easiest way to find true 20 wt.

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I thought it was 20. Thank you

What about doing an oil change? Is there a way that you drain them for doing one?

It is not necessary to do a oil change. Just top it off. If you look close on the damper rod there is a high level mark. If you do over fill the damner it is no big thing as the engine will burn the excises. I have personally found that 20wt works the best for me. This is the wt that is recommended by Nissan/Datsun when they were dealing with the SUs.

20wt and the best way to do the oil it a straw hold one finger over the end wen you git it in the oil it will stay till you git it in the su piston.

Arne's got it right. I bought my oil from my local crotch rocket shop. They thought I was crazy too when I told them I needed oil for my carbs! They ordered it for me in a 1 litre bottle for $12.00. A lot more than I need and a lot more than I thought I would spend but it is correct.

Sounds like John Mcgarvie has a system that may work for removing most of the existing oil.

Good luck.

John

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Thank you all. I was talking an oil change for the carbs just because I dont know any history on past owners and service. With that and knowing the oil maybe the wrong wt. or atleast going on 38 years old. I would rather be safe then sorry.

We have about 15 bikes at the shop on any givin day. So fork oil and 20W is almost always sitting on a shelf.

Funny, but you should have seen the looks on the faces of the guys at our shop when I said I think I need too check the carb oil LMAO LOL

Thank you.

Funny stuff there man. I've received those looks as well. LOL

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