Topping off the hydraulic piston damper - SU carbs

(Bill) #1

The Bentley handbook has me ‘topping off’ the hydraulic damper periodically. I’ve never so much as checked the level before so this morning loosened and then fully removed the damper valve. It appeared as though there was plenty of oil.

Is there any sort of technique to checking the level and should I have fully removed the damper valve - or do you leave it in while filling?


(Erica Moss) #2

I take it out and fill to half inch below the top of the tube.

(69roadster) #3

I believe they should be topper off weekly

(Dennismo) #4

Every few months I unscrew the damper, pull it up about a half inch and push it back in checking that I feel the resistance of the oil in the piston.

I only have to add oil if I take out the piston to clean it.

Dennis 69 OTS

(Bill) #5

Thank you. None of them seemed even remotely low…

(Dennismo) #6

The key thing is that when you push it back down, that you feel the resistance from the oil
Dennis 69 OTS

(69 FHC ) #7

I just estimate how much is needed and dribble some in. Someone correct me if I’m wrong, but I don’t believe there is any harm is overfilling it a bit. The extra just get’s forced out and burned by the engine.

While putting together my ECOL travel kit I added a small bottle (cleaned out hotel shampoo bottle) of 20 wt. fork oil for any top off needed on a trip.

(Mark Gordon) #8

As stated earlier, all that you need is enough so that you feel resistance the last 1/2" or so as you screw the piston back down. 3-in-1 oil is 20 wt. and a small can of it is handy to carry in the wheel well should topping up be necessary while on a trip. Looking forward to seeing you in a few weeks, John.