Ian Vincent Posted June 20, 2017 Report Share Posted June 20, 2017 Following on from the post on this forum about Masterlube, I've been meaning to get some because I too suffer from squeaking suspension. As I now only live about 30 miles from Revington TR, I thought yesterday would be an ideal time to drive there. What I had forgotten was that my route was going to take me right past Worthy Farm where the preparations for Glastonbury were in full swing so there was a fair amount of sitting in traffic jams on a very hot afternoon. What was a result was that the cooling system performed as it should; whenever I hit a jam and the temperature started to rise the fan cut in and brought it down again; otherwise the needle stayed resolutely in the middle of the dial. I did however have issues with the idling which dropped from about 750 to 500 RPM and was accompanied by significant misfiring and popping when I started moving again. On a couple of instances I had to dab the throttle to stop the engine cutting out. When I got back home after a good end to the run which enabled me to drive normally again, I pulled a couple of plugs and they were both very black. Hitherto when I have checked the plugs (as I do periodically) they have been sandy brown coloured, even verging on grey. Why would the mixture setting have suddenly gone off? The only thing I have done recently is put thicker oil in the carb dashpots. The other issue related to the oil pressure. It went down to about 60 PSI at 2000 RPM and dropped to about 10 psi when idling. The oil pressure is normally up at 70 at 2000 RPM but I accept that yesterday it was very hot and the oil would have been thinned right down. The car is due an oil change anyway, would putting 10w 60 oil in it help, I am not prepared to pull the engine or drop the sump and start replacing shells etc., although I might be prepared to do that in the winter. Any suggestions welcome please. Rgds Ian Quote Link to post Share on other sites
Guest ntc Posted June 20, 2017 Report Share Posted June 20, 2017 Ian Sounds fine to me in that traffic and heat did the engine drop rpm when the fan kicked in? Quote Link to post Share on other sites
Alec Pringle Posted June 20, 2017 Report Share Posted June 20, 2017 Hi Ian, you're just down the road from me now - Mere ! We all have to learn the hard way about Glastonbury . . . . . I shouldn't worry about the oil pressure given yesterday's temperature, and nor would I worry about the spluttering . . . . . very hot dry air, less dense, you're running rich to start with. Then as Neil points out the fan kicks in and drags down the rpm given the extra load on the dynamo/battery. It ain't broke etc . . . . . Cheers, Alec Quote Link to post Share on other sites
Ben Freer Posted June 20, 2017 Report Share Posted June 20, 2017 (edited) We had similar issues today whilst queuing for the Chunnel for an hour. Engine temperature was fine and managed well by the Revotec fan. However the under bonnet temperature was immense. That and the ambient air temperature made the bonnet almost too hot to handle. I put it down to fuel vaporisation and a few minutes stationary with the bonnet up soon calmed things down. Edited June 21, 2017 by Ben Freer Quote Link to post Share on other sites
Lebro Posted June 21, 2017 Report Share Posted June 21, 2017 I was also in that approximate area yesterday - Gillingham then New Forrest, then back to Gillingham, then home. (see At the bar) TR never overheated coolant wise, but as mentioned above, when sitting in traffic the idle revs do drop. Undoubtedly due to over rich mixture. Cure for these hot days would be simply to lean out the carbs by a couple of flats. Bob. Quote Link to post Share on other sites
Motorsport Mickey Posted June 21, 2017 Report Share Posted June 21, 2017 If it makes you feel better even when racing the car we used to take note of the weather and barometer and adjust the carbs to make the most of it. Mick Richards Quote Link to post Share on other sites
stuart Posted June 21, 2017 Report Share Posted June 21, 2017 With the modern fuels being made up of a lot of things like butane and other aromatics on a very hot day these will be evaporating off pretty quick and with less dense air its not surprising it was running rich. Dont bother to try re-tuning as when it starts to cool down it will be back to its normal running. Stuart. Quote Link to post Share on other sites
tim hunt Posted June 21, 2017 Report Share Posted June 21, 2017 The fall in idling speed when stationary in hot ambients is usual and quite understandable as explained above. In these circumstances I simply pull the choke out 1/4", which raises the idle speed sufficiently to avoid the risk of stalling whilst not further enrichening the mixture. I often forget to return the choke when getting going again but am reminded by the unusually fast idle speed when I next come to a halt, no harm done. Tim Quote Link to post Share on other sites
Ian Vincent Posted June 21, 2017 Author Report Share Posted June 21, 2017 Very many thanks to all for the responses, I am reassured. Rgds Ian Quote Link to post Share on other sites
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