Sam C Posted October 30, 2008 Share Posted October 30, 2008 Now, I've just cleaned up and refurbished my carbs and, to get them going, I've just stuck some WD40 in the dashpots for oil. I expect everyone's going to tell me this is the worst thing you can possibly do but I had in the back of my mind that light oil is better than ordinary engine oil. So: what does everyone else put in their dashpots? The car's a GT6 - so Stromberg carbs. Cheers Link to comment Share on other sites More sharing options...
willcolumbine Posted October 30, 2008 Share Posted October 30, 2008 Errrr....engine oil. WD40 is way too light! Link to comment Share on other sites More sharing options...
ferny Posted October 30, 2008 Share Posted October 30, 2008 The idea is that it prevents the needle from flying up under acceleration. The thinner the oil then less resistance. 3in1 is as thin as you want to go and engine oil should be fine. Everyone has their own preference.I'#ve no idea if K&N oil is any good for it. ;D Link to comment Share on other sites More sharing options...
GT6boy Posted October 30, 2008 Share Posted October 30, 2008 I think you meant 3in1 didn't you- otherwise you'de have had to decant the WD40 from the aerosol :-/. I use engine oil. Its an easy little experiment to try the different oils, but you should make sure you let the engine get up to a good under bonnet temperature- so the oil in the carbs gets up to the usual operating temperature. Link to comment Share on other sites More sharing options...
Royboy66 Posted October 30, 2008 Share Posted October 30, 2008 engine oil in mine! 8) Link to comment Share on other sites More sharing options...
Nick Jackson (2) Posted October 30, 2008 Share Posted October 30, 2008 I know you have Strombergs, but for SU's Burlen Fuel Services told me to use SAE20 (engine) oil, but NOT a multigrade. They sell this in little bottles at an extortionate price! Link to comment Share on other sites More sharing options...
thealligator Posted October 30, 2008 Share Posted October 30, 2008 97679 wrote:I know you have Strombergs, but for SU's Burlen Fuel Services told me to use SAE20 (engine) oil, but NOT a multigrade. They sell this in little bottles at an extortionate price! I know Burlen do a sae 20 oilI think it what suites your set up My Spitfire runs better with little or no oil I just use a spot of 3 in 1 Link to comment Share on other sites More sharing options...
heraldhabitat Posted October 30, 2008 Share Posted October 30, 2008 Had MOE tuned at Aldon Automotive before the RBRr and they recommended auto transmission fliud in my HS6's, however I have always found engine oil perfectly acceptable over the years. Link to comment Share on other sites More sharing options...
Greeks Posted October 30, 2008 Share Posted October 30, 2008 I've been advised ATF too ... but when I mentioned it on here everyone thought I was barmy :B Link to comment Share on other sites More sharing options...
ferny Posted October 30, 2008 Share Posted October 30, 2008 I've got loads of the stuff now so I'll give ATF a go. Which type is best? ;) Link to comment Share on other sites More sharing options...
Greeks Posted October 31, 2008 Share Posted October 31, 2008 The stuff you haven't got. You better get down the shop. Link to comment Share on other sites More sharing options...
JohnD Posted October 31, 2008 Share Posted October 31, 2008 This discussion betrays a basic lack of understanding about what the carburettor dashpot/damper is supposed to do.It's not black magic.An SU or Stromberg carb is a "Constant velocity" device. It changes the diameter of the orifice at the fuel jet, so as to maintain a constant air/fuel mixture, by allowing the piston to rise and fall in response to the changing demands of the engine, moving the needle in the jet to allow more or less fuel to escape into the changing air flow. (NB do not confuse 'flow' with 'velocity'.)On acceleration, the carburettor piston rises as the engine draws in more air. But for acceleration a slightly richer mixture is desirable, so the damper/dashpot slows the rise. Until it reaches equilibrium, the orifice is narrower, the air velocity is greater and a slight excess of fuel is drawn into the air flow, to provide the richer mixture.The carburettor is designed so that with engine oil in the dashpot this change is optimum for the majority of drivers. If, however, you want to achieve maximum fuel economy and drive with featherweight boots on, accelerating and braking seldom and then lightly, a thinner dashpot oil will produce less enrichment on acceleration and less fuel consumption. If you are a hot-shoe road burner then a heavier oil may suit you, but the only way is to try oils of different viscosities. There is no 'right ' oil.John Link to comment Share on other sites More sharing options...
mikeyb Posted October 31, 2008 Share Posted October 31, 2008 well I for one admit to not previously knowing this basic understanding - thanks for the clarity John, I look forwards to a bit of experimentation! Link to comment Share on other sites More sharing options...
Lord Sorbington Posted October 31, 2008 Share Posted October 31, 2008 Greeks wrote:I've been advised ATF too ... but when I mentioned it on here everyone thought I was barmy :BWhen will you learn? If you switch your brain off and try a little harder to conform instead of offering contrary opinions on everything then you won't have this problem. ;DAs for dashpot oil, I tend to use 3 in 1 as it comes in a handy squirty container. I've tried engine oil too but I've never found the grade used to make any difference on any car. As long as the piston is damped slightly, that seems to be enough. Link to comment Share on other sites More sharing options...
shedmonkey Posted October 31, 2008 Share Posted October 31, 2008 I use tescos extra virgin olive oil with a hint of garlic......bollocks sorry wrong web site!but in my dash pots I always worked on this theroyThin oil-faster piston/damper action hence less "riching up" (my home made word I made for my self when learning about SUs)Thick oil-slower piston/ damper action hence more riching up when u give it a boot fullTip-run the car with no oil in the dash pots and it soon becomes obvious what the damping action does!-(I forgot to put oil in once)Also dont forget about the action of the spring! Link to comment Share on other sites More sharing options...
Clive Posted October 31, 2008 Share Posted October 31, 2008 MikeyB wrote:well I for one admit to not previously knowing this basic understanding - thanks for the clarity John, I look forwards to a bit of experimentation!Treacle? Link to comment Share on other sites More sharing options...
Lord Sorbington Posted October 31, 2008 Share Posted October 31, 2008 ajp wrote:I use tescos extra virgin olive oil with a hint of garlic......bollocks sorry wrong web site!Also try the toasted sesame oil, not too much though, it has quite a strong flavour. Link to comment Share on other sites More sharing options...
Nick B. Posted October 31, 2008 Share Posted October 31, 2008 My piston dampers pops of when I drive hard. Has that something to do with to thin oil (3 in 1 oil)CheersNick Link to comment Share on other sites More sharing options...
shedmonkey Posted October 31, 2008 Share Posted October 31, 2008 hmm you mean the black threaded part comes right out? brother had a sherpa van that did that! Link to comment Share on other sites More sharing options...
Nick B. Posted October 31, 2008 Share Posted October 31, 2008 Yep - black threaded part does not hold. Let the foot down and pop they go. :(CheersNick Link to comment Share on other sites More sharing options...
Lord Sorbington Posted October 31, 2008 Share Posted October 31, 2008 Maybe the plastic threads are knackered? When I got the 2000, the threads on one damper were stripped so the damper moved up and down with the piston, it didn't screw into the carb at all.I fitted a replacement. Made no difference to the running........ Link to comment Share on other sites More sharing options...
Nick B. Posted October 31, 2008 Share Posted October 31, 2008 Most likely you ar right on this one sorbs. The thread doesnt look knackereded (it is only one and a half thread anyway holding the damper on). Replacement might be needed. Perhaps just keep going with a small piece of duct tape. Will try engine oil and se if it helpsCheersNick Link to comment Share on other sites More sharing options...
Pete Lewis Posted October 31, 2008 Share Posted October 31, 2008 I wonder why triumph specified engine oil in all the handbooks and manuals even in haynes, Guess as it was tried and tested to suit most Uk driving styles, JohnD is spot on and if it works better when filled with cats pee then something else is not set correctly in the first place we use the specifications in the books for plug and point gaps and tappet clearances so why ignore the oil requirements then there's always the trunions ??? Ho Hhmmm pete Link to comment Share on other sites More sharing options...
ferny Posted October 31, 2008 Share Posted October 31, 2008 sorbs wrote:As for dashpot oil, I tend to use 3 in 1 as it comes in a handy squirty container. Hair dye comes in a nice little bottle with a pointy screw cap. Handy for filling with oil for jobs like this. Nick B. - try wrapping some ptfe tape around the thread to bulk it out a bit? Link to comment Share on other sites More sharing options...
Greeks Posted October 31, 2008 Share Posted October 31, 2008 So have you got ginger carb. oil then? Link to comment Share on other sites More sharing options...
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