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TR2/3/3A TR3 SU dampers again....how often to top up?

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K

karls59tr

Yoda
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This may have been discussed before but.....I've been using ATF in the dampers and get good throttle responce but I've noticed it dosn't take long for the level to go down. Is this normal?...and yes I'm filling to the correct level not right to the top. A friend of mine with a 3 says he never bothers checking the damper level!....there must be a down side to that?
 
When you say, "go down," it makes me wonder how far down, and would they keep going down?
A test: Unscrew the damper and raise it a bit. Then, press it back down. If you can feel resistance before the threads engage, you have enough fluid in there. Do yours ever fail this test?
If the oil level is getting below that point, you have a leak worth worrying about -- though, I have no idea what the cure would be... If the oil never gets below that point, it's not a "problem."
 
It's a mystery where oil could leak. There's only one aperture in the oil well (that's what SU called it), and that's at the top. So when you fill it, oil will be displaced when you put the damper back in, and if you've over-filled it, it will run down inside the dashpot. Again, when you take the damper out, particularly if you do it in a hurry, you'll probably displace some oil.
So the moral is, to use less oil, check less often!
BTW, SU recommended 20wt oil in the dampers as a rule, and never more than 30wt.
 
The earlier manuals said, in effect, to overfill the carbs slightly, every 6000 miles (or something like that). I believe the reason was so the excess would work it's way down between the rod & dome, to lubricate the tight sliding fit.

But as Moses said, as long as you can feel some resistance when inserting the damper rod, there is enough oil for proper operation.

And if the level is too low, I'm pretty sure you will notice the tendency to stumble when you first open the throttle.

FWIW I found that I got better response with 20 weight; even ATF gave me just a bit of lean bog (tho certainly much better than nothing at all).
 
I was trained to add some, replace the cap/rod, the push the piston up sharply and any excess with squirt out of the hole in the cap. What's left is the right amount. Something a little heavier than ATF will give a richer mixture when accelerating hard.

Peter C
 
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