Oil pressure or the lack of??

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jagnut66
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Oil pressure or the lack of??

Post by jagnut66 »

Hi,
My problem is that when I depress the clutch the oil light comes on, yet when I blip the throttle it goes out again. This problem seems to be worst when the engine has warmed up. I have had a mechanic listen to it and he said it sounded ok, so I have purchased a new oil pressure switch online (hoping for a simple fix when it arrives) but in case this doesn't solve it any thoughts on this matter would be appreciated.
Many thanks in advance for any advice you might have.
Mike.[frame]Image[/frame]
1954 Series 2: 4 door: "Sally" -- Back on the ground with (slave) wheels and waiting to be resprayed......
1970 Triumph Herald 1200: "Hetty" -- Driven back from Llangollen in Wales (twice.....)
les
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Re: Oil pressure or the lack of??

Post by les »

Possibly pressing the clutch slows the revs down, therefore making the lamp to go out.

PSL184
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Re: Oil pressure or the lack of??

Post by PSL184 »

Most likely nothing wrong at all. Tickover may be a little slow and the clutch could be in need of adjustment as it can over travel and increase the load on the engine causing tickover to fall below the point when the pump can keep up.
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bmcecosse
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Re: Oil pressure or the lack of??

Post by bmcecosse »

As above - the pressure is obviously slightly on the low side - and with a slow tick-over the clutch is slowing it enough to bring the light on. As long as it stays off when running - it will be fine for many many miles. May be worth doing an oil and filter change - use 20W50 oil (ASDA is fine!) - and MAKE SURE the little plate and spring are present and correct under the cartridge filter - many get thrown away with the old filter, and then there is no more filtration :cry:
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jagnut66
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Re: Oil pressure or the lack of??

Post by jagnut66 »

Hi, Thanks for your replies, this turned out to be the oil pressure relief valve and spring sticking open! Replacement of said offending items seems to have cured it. Once again, many thanks. Mike.
1954 Series 2: 4 door: "Sally" -- Back on the ground with (slave) wheels and waiting to be resprayed......
1970 Triumph Herald 1200: "Hetty" -- Driven back from Llangollen in Wales (twice.....)
bmcecosse
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Re: Oil pressure or the lack of??

Post by bmcecosse »

I have my doubts! But not to worry - as long as it's ok now. Your best buy is an oil pressure gauge - then you will KNOW what's going on.
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Nuffles
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Re: Oil pressure or the lack of??

Post by Nuffles »

Whilst on the topic, what's the ideal oil pressure? I have a gauge in Aristotle and it seems to hover about the 50lb/sq in in use depending on revs. Is this about right? Thanks. 1098cc engine btw.
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bmcecosse
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Re: Oil pressure or the lack of??

Post by bmcecosse »

That's 'ok' - it should really sit up at 60/70 psi when doing decent revs - but 50 is fine. The gauges are often not that accurate!
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jagnut66
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Re: Oil pressure or the lack of??

Post by jagnut66 »

Hi,
With regard to oil pressure gauges (and indeed other classic look gauges) I have now taken the above advice and fitted one supplied by: http://www.merlinmotorsport.co.uk/INSTR ... index.html
I chose a 'Smiths' electronic gauge and bought the corrisponding electronic sender, which screws straight into where the oil pressure switch is normally sited on the engine and is simple to wire up.
This, as predicted, gives a far more accurate reading (far better than the basic oil warning light which it replaces, as you can't have both).
I went for the magnolia (cream) faced dials (chrome surrounds) and I think they look really good and go well with my early speedo.
Many thanks for all the advice (and interesting debate).
Best wishes,
Mike.
[frame]Image[/frame][frame]Image[/frame]
1954 Series 2: 4 door: "Sally" -- Back on the ground with (slave) wheels and waiting to be resprayed......
1970 Triumph Herald 1200: "Hetty" -- Driven back from Llangollen in Wales (twice.....)
mike.perry
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Re: Oil pressure or the lack of??

Post by mike.perry »

You can have both an oil pressure gauge and warning light. You need a T piece adapter
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jagnut66
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Re: Oil pressure or the lack of??

Post by jagnut66 »

[b]Interesting, as I tried this first as I had a T piece already and the gauge wouldn't work with it (the T piece wasn't blocked), though it now works fine on it's own.....
Regards, Mike.[/b]
1954 Series 2: 4 door: "Sally" -- Back on the ground with (slave) wheels and waiting to be resprayed......
1970 Triumph Herald 1200: "Hetty" -- Driven back from Llangollen in Wales (twice.....)
bmcecosse
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Re: Oil pressure or the lack of??

Post by bmcecosse »

How strange! It is normal to use a T - must have been a kink in the pipe.....
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kjm
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Re: Oil pressure or the lack of??

Post by kjm »

Hi, our car has a similar problem to that of Jagnut66, on starting a cold engine , there is a metallic sound for a couple of seconds until the oil is pumped around , she is then fine until warmed up , then when you depress the clutch to change gear or to coast up to a junction the oil light comes on but quickly goes out once accelerating again . When warm at higher speeds a slight noise can be heard, hard to describe , she had Comma classic 20w50 approx 1500 miles ago , I did not check the filter as I find them difficult to re-seal , someone suggested I should not assume there is a filter fitted , should I be worried by this ?

bmcecosse
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Re: Oil pressure or the lack of??

Post by bmcecosse »

That rattle on start up is the big ends knocking! If you fit new big-end shells now - you may just get away with it. However if the mains are also worn - it's an engine out job to get at them, and you may as well fit an exchange re-ground crankshaft (and a new oil pump!). The Bull Motif exchange crankshafts are a screaming bargain price - it is probably the way to go. And yes - you should have checked/fitted a new filter - i've never had any bother sealing them ??
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kjm
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Re: Oil pressure or the lack of??

Post by kjm »

Thanks

mike.perry
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Re: Oil pressure or the lack of??

Post by mike.perry »

Turn the engine over without the choke or accelerator until the oil pressure light goes out before attempting to start it.
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