Menno van Rij Posted May 7, 2009 Report Share Posted May 7, 2009 Hi all, I've driven a few hundred miles now with my TR, and all's performing amazingly well. Earlier tonight I took the car for a spin. I looked at the oil pressure gauge and I realized that I have no idea about the correct and healthy oil pressure for a TR's engine. I noticed about 50 psi at about 2700 rpm with a fully warmed engine. Regards, Menno Quote Link to post Share on other sites
Guest ntc Posted May 7, 2009 Report Share Posted May 7, 2009 (edited) Hi all, I've driven a few hundred miles now with my TR, and all's performing amazingly well. Earlier tonight I took the car for a spin. I looked at the oil pressure gauge and I realized that I have no idea about the correct and healthy oil pressure for a TR's engine. I noticed about 50 psi at about 2700 rpm with a fully warmed engine. Regards, Menno Ideal Regards Neil Edited May 7, 2009 by ntc Quote Link to post Share on other sites
Menno van Rij Posted May 7, 2009 Author Report Share Posted May 7, 2009 Neil - Thank you! Menno Quote Link to post Share on other sites
vivdownunder Posted May 8, 2009 Report Share Posted May 8, 2009 Hi Menno, A healthy engine can show normal oil pressure up to 70psi at 2000rpm, but yours is quite OK at 2700rpm with warm oil. At idle, a warm engine can drop down to 20psi and still be protected, although they should stay around 40psi. It depends somewhat on the viscosity of engine oil being run, and wear factors. I find 20W-50 multigrade is a good all year round oil. Regards, Viv. Quote Link to post Share on other sites
67_gt6 Posted May 8, 2009 Report Share Posted May 8, 2009 Hi, after a hard run I get about 13 PSI at 700 RPM. This hasn't changed in 15K miles. I believe the safe lowest value is 10PSI per 1000 RPM. andy Quote Link to post Share on other sites
ianc Posted May 8, 2009 Report Share Posted May 8, 2009 Back in the early 1960s, my old TR2 would show about 50 psi when I joined the M1 near Watford and about 25 psi at 100 mph when leaving the M45 near Coventry, having cruised most of the way at or near that speed (legal then!). When ticking over, after this cruising, the needle was only just off zero (possibly 10 psi). However, the oil was circulating and both lubricating the bearings and removing heat from them - that's an important part of the job of the oil. That car, which was unmodified apart from disc front brakes, was amazing in that it could perform like that, could wind up well beyond 110 mph, yet returned 30 mpg. I think it was almost frictionless because it was used every day and was thrashed! It's worth remembering, too, that your oil pressure gauge was a cheap and cheerful piece of kit which is unlikely to have been calibrated since the car was built at Coventry (and how accurately did its maker set it before supplying it to Triumph?) - so how accurate is its reading now? Short of removing it and getting it checked on equipment you can trust, I don't suppose you'll ever know! When I worked in the instrumentation and control business, we used a test device with a hydraulic ram and calibrated weights to set up our instruments - knowing the diameter of the ram and the applied weight, the pressure was known to a very high accuracy. Ian Cornish Quote Link to post Share on other sites
Tr4Tony Posted May 8, 2009 Report Share Posted May 8, 2009 Menno All sounds ok, but you may want to take the precaution of tapping an oil pressure switch into one of the three bolts into the oil gallery on the LHS (distributer) side of the engine ....... you can connect this to a light on the dash. This give you a visual warning of when oil pressure drops below 20psi (or whatever the switch is calibrated at) and is good insurance. To put this in context, my gauge always works but when i clobbered the oil cooler and the OP vanished it saved the engine. Regards Tony Quote Link to post Share on other sites
BrianC Posted May 9, 2009 Report Share Posted May 9, 2009 (edited) Hi, after a hard run I get about 13 PSI at 700 RPM. I can't believe any gauge can be that accurate. I'd assume at least +/- 5 psi at low end and =/1 10% at high end. [Ah - I see Ian has made a similar comment] Edited May 9, 2009 by BrianC Quote Link to post Share on other sites
angelfj Posted May 9, 2009 Report Share Posted May 9, 2009 (edited) Hi all, I've driven a few hundred miles now with my TR, and all's performing amazingly well. Earlier tonight I took the car for a spin. I looked at the oil pressure gauge and I realized that I have no idea about the correct and healthy oil pressure for a TR's engine. I noticed about 50 psi at about 2700 rpm with a fully warmed engine. Regards, Menno Hello Menno I don't recall you mentioning this, but during the restoration of your 3A, did you refurbish the oil pressure relief valve? This valve is contained within the head of the oil filter. Over time the spring can weaken and/or the face of the plunger can wear. It's also a good idea to replace the hard steel ball. If these parts are worn, pressure can be bled off at a value lower than specification. Replacement parts (ball, plunger and spring) are available and are cheap. All of this is explained in detail in Bentleys. Cheers, Frank Edited May 9, 2009 by angelfj Quote Link to post Share on other sites
Royzeboyze Posted May 9, 2009 Report Share Posted May 9, 2009 Hi All, My TR3A when started runs at 70psi, when warm and hot and under power can go up to nearly 100 psi at 70 mph, or through the gears at 4500 revs, on tickover never lower than 45 or 50. You can adjust the oil pressure as you all know!. I don't worry about this. The engine sounds OK with no rattles, it has only done 2750 miles since 1992. If it blows up so be it. There seems to be plenty of oil getting to the rockers. Royzeboyze Quote Link to post Share on other sites
Louis Metelko Posted May 10, 2009 Report Share Posted May 10, 2009 Don't know if it was the genius of Triumph's engineers or what but I have always used the "quick scan" method on the minor gauges. If all of the needles are straight down all is well. Intently studying the movement of the minor gauges is like watching the stock market - it will drive you nuts. Lou Metelko Auburn, Indiana USA Quote Link to post Share on other sites
MCOOPER53 Posted May 11, 2009 Report Share Posted May 11, 2009 The following is from the TR3 Instruction Book. Oil Pressure Gauge. Indicates pressure of oil at the bearings. The gauge should read 70 lb./sq. in. minimum when the car is travelling at normal speeds and the oil is hot. Low pressure may be registered when the engine is idling or running at low speeds ; this is quite normal. Quote Link to post Share on other sites
KEL Posted May 11, 2009 Report Share Posted May 11, 2009 (edited) hi guys my oil pressure when cold is about 80 to 90 & drops to 70 when hot -- tr3 it was rebuilt 2 years ago by me & allan peatfield who was kents main man then . regards kel Edited May 11, 2009 by KEL Quote Link to post Share on other sites
Guest ntc Posted May 11, 2009 Report Share Posted May 11, 2009 Don't know if it was the genius of Triumph's engineers or what but I have always used the "quick scan" method on the minor gauges. If all of the needles are straight down all is well. Intently studying the movement of the minor gauges is like watching the stock market - it will drive you nuts. Lou Metelko Auburn, Indiana USA Hi Lou You are spot on to much oil pressure can be as harmfull as not enough Menno's is ideal Regards Neil Quote Link to post Share on other sites
Menno van Rij Posted May 14, 2009 Author Report Share Posted May 14, 2009 I went by the workshop this morning and I asked the guys if they had adjusted the pressure valve when they were working on the car. Alan confirmed this. He told me that he had used a pressure gauge with a certificate (like a torque wrench certificate). He adjusted the pressure in three steps: first, he used the starter motor and adjusted the valve, making sure that the pressure was fairly high. A few months later, when I had installed the carbs. he adjusted the carbs., using a 4gas tester. That's when he did the second adjustment: engine warm (not hot!), on tick over, he adjusted the pressure valve again. The last test was when he took the car for a spin just before the MoT. After 10 miles, he adjusted the valve again: about 55 psi@ 2500 r/pm. On my car, the dashboard gauge is roughly correct: the read out is a little less than the read out on the certified pressure gauge. Alan ensured me that a dashboard gauge is like a politician: they move under pressure but never can be trusted (...), none is telling the truth. Menno Quote Link to post Share on other sites
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