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Discussion Starter · #1 ·
So i took her out on the highway for the first time, and I was cruising at about 5000 rpm, and i noticed the oil light was lightly flickering. My instinct told me to pull over, but i was almost home so i kept going. I noticed more oil had come out of the rocker lines than usual. So, is this from losing oil pressure at a leak, or an electrical oddity? any reccomendations on new seals?
 

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I would suggest the easiest actions first - if the oil leaks are at the oil hoses try tightening them to stop the leaks (however if the leaks are at the rocker hose this is after the pressure switch so is unlikely to cause the light to flicker) - next fit a new oil pressure switch -see if it improves
 

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The pressure at the oil light switch has nothing to do with the feed to the rockers.

The sensible thing to do is measure the oil pressure with a gauge plumbed in place of the switch. If cold pressure is ok, go for a ride and get the oil hot and see of pressure is still ok.
 

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The pressure at the oil light switch has nothing to do with the feed to the rockers.

The sensible thing to do is measure the oil pressure with a gauge plumbed in place of the switch. If cold pressure is ok, go for a ride and get the oil hot and see of pressure is still ok.
How is oil pressure separated between the rockers and the pressure switch?
 

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How is oil pressure separated between the rockers and the pressure switch?[/QUOTE

Forget about arguing with me and offer any help you can, to the guy with the oil light.

Your Triumph manual has a diagram of the oil system. Have a look at it.
No argument, I merely asked a legitimate question. If you choose to be childish and not answer it for everyones benefit, so be it.
 

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So i took her out on the highway for the first time, and I was cruising at about 5000 rpm, and i noticed the oil light was lightly flickering. My instinct told me to pull over, but i was almost home so i kept going. I noticed more oil had come out of the rocker lines than usual. So, is this from losing oil pressure at a leak, or an electrical oddity? any reccomendations on new seals?
the oil pressure light or gauge reads the oil pressure between the pump main outlet and the near side of any restrictions to the oil flow-- the big end bearings, the oil pressure relief valve, and the exhaust tappet feed. the other side of those restrictions is all zero-pressure drainback. after the sump pickup there's a bit of negative pressure until the return oil gets sucked back to the return plunger of the oil pump. i don't have any idea what the pressure is on the positive side of the return oil pump plunger-- there's no gauge and it's regulated only by the restriction in the line that causes some amount of flow to go to the rockers.

the oil pressure light isn't connected to the rockers, but if your oil light is flickering at 5000 rpm, then either you have a low oil pressure problem on the feed side or the sender is bad. the first is expensive, the last is cheap. if there was more seepage at the rocker lines it may have been due to warm, thin, oil, or a loose hose clip

see if an automotive store can fix you up with a gauge and an adapter so you can tell for sure. i think by 76 the fitting was a standard pipe taper. you can even just buy any automotive oil pressure sender with the correct thread and stick it on to check-- any of them will work well enough to tell you if your oil pressure is way low.
 

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get the gauge. Check the pressure

if pressure is good, it is an easy fix with a new sender. If the pressure is very low. You will need to start with the easiest possible solution, and that would be a blown out crankshaft oil pressure seal.

Chances are you blew out the crankshaft oil seal inside the timing cover. Once that goes your oil pressure drops to a level close to zero. Your oil pressure reading will tell you what you are facing.

S
 

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Discussion Starter · #15 ·
Probably fair to mention since I forgot to put in the main post... It only did this at 5000 or above. Once I got off the highway the light went completly out. Then revved up again from a stoplight, and the little flicker came on again at 5.
 

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something is weird. the pressure should go up with rpm. sounds like a bad sender with an intermittent ground on the oil pressure sending light circuit. the light is fed by a hot wire- when the pressure is low the switch grounds the circuit and the light goes on.

if vibration grounds a bad sender at high rpm then it will flicker as you describe.
 

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Hi,

if vibration grounds a bad sender at high rpm then it will flicker as you describe.
But Check The Pressure With A Gauge. :)

Easiest place to fit a gauge either temporarily or permanently is in place of the o.p. switch in the front edge of the timing cover. The o.p. switch thread is 1/8"NPS (National Pipe Straight); temporarily, the more-common NPT can be used.

The pipe to the gauge is likely to stick out straight from the coupling. The timing case around the o.p. switch is very thin, so ensure nothing can be hit by the fender or front wheel when the steering's turned.

Hth.

Regards,
 

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Probably a bit early for this sort of theorising, but oil pressure can suffer a collapse at higher rpm, if gravity flow from the oil tank can't keep up with the oil pump demand.

I've only seen it once, caused by oil that was too thick (SAE 50). I suppose other sorts of restriction, such as a flattened pipe, could have the same effect.
 

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I once had the same problem with my 1977 T140. It happened after I changed my oil. I used a brand of oil I had never used before.(Valvoline 20W50) I was out for a ride and the oil light came on. I pulled over immediately and could find no obvious problem. Rode home with the light on or flickering. Checked the oil pressure when I got home and it was fine. I drained the oil and replaced it with my normal oil (Castrol 20W50) and that solved the problem. Never happened again.
 
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