Question about 2004 Yamaha V Star Classic

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T140 Triumph 750 Bonneville Oil Pressure

I have a 76 750 T140 Triumph Bonneville, At low idle the oil light comes on Driving down the road it goes off? My Oil Sending switch is 33 years old kinda rusted could it be that. I was thinking I could unscrew the oil sending unit and screw in a oil pressure Gauge? What should the oil pressure Be?

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Before listening to the doom merchants try this first. Make sure the oil seal in the timing case (not points cover - the crankshaft one) is the right way round (spring side showing) and seated OK. When fitting case oil up the seal well and turn engine over (plugs out) while tapping the case home gently with your fist - if this seal is not dead right it will alow enough oil passed it to throw the pressure switch open without causing any damage. Had my T140 32 years. 

Posted on Sep 04, 2009

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Pressure should be 60 lb/in . I have a '78 T140D and at the moment have an oil pressure gauge screwed directly into the engine case. I am looking for an adaptor so that I can run a hose up to the handlebars and mount the gauge there so if you find one anywhere perhaps you could let me know.



Posted on Aug 05, 2009

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You will most likely find a low oil pressure problem. It is possible it is the switch, but with a bike that old, I would guess more oil pump clearance issues, or other worn parts in engine. You can try running some 20w50 oil to take up some clearance, but it is only a patch. Oil pressure should be no less than 7-10 psi.

Posted on Jul 15, 2009

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