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TR2/3/3A Dash Pot Oil

Everybody has a recommendation and they are all different. I couldn't figure out who to believe so I went with the guys who made the carbs and bought a bottle of genuine SU branded dashpot oil.
 
One oft quoted rule of thumb is too use the same weight/oil in the dashpots that you are using in the crankcase.

For almost anything you pick you'll find someone to agree with you and many who don't.
 
What CJD said. The only thing that didn't work was WD40. ATF, 20w, 30w, 10w-30, 10w-40, 5w-30 any medium grade oil/lubricant will work fine. I have tried many different, unless you go way too thick or way too thin you won't notice a difference.
 
What CJD said. The only thing that didn't work was WD40. ATF, 20w, 30w, 10w-30, 10w-40, 5w-30 any medium grade oil/lubricant will work fine. I have tried many different, unless you go way too thick or way too thin you won't notice a difference.
I found ATF seemed to give a quick throttle response. I've heard 3 in oil is 20 SAE and should be ideal.
 
Not mentioned yet is the reason for damper oil...It's to slow down the rate at which the air valve rises. During that short interval of time, which is really short, the slow response actually enrichens the fuel/air mix which is condusive to smooth acceleration.
ZS carbs, btw, do best with engine oil rather than any real thin stuff...maybe the difference is because of the ZS carbs Air Valve diaphragm's complete sealing of the suction chamber
 
I just realized that whale oil was still available when these cars were built. Wonder if that would have been a recommendation if we had internet in the 60's?

Sorry...been cooped up too long.
 
I did a test on damper oil on my mini. I tried 5wt to 50wt. Never noticed a difference. As said above, now I just make sure there is oil in there.
 
Though oddly there were some SU applications that specified no oil in the dampers. One example (I believe) is the AC Ace with the Weller engine.
 
I just realized that whale oil was still available when these cars were built. Wonder if that would have been a recommendation if we had internet in the 60's?

Sorry...been cooped up too long.


A local club member has a 1934 MG PA which has inscribed on the damper caps "USE BICYCLE OIL". I don't know if there is any whale oil in that.

And Geo, my TR3 will run but horribly without damper oil.

Tom
 
My Dad used 3N1 oil in his Jag XK140FHC, and his '49 MG TC, I used it in an MGB, TR3B and current TR3B because thats what he used. It may have had something to do with being in Fairbanks with the XK140 (daily driver in '58-59) but it never failed....
 
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