Oil Pressure relief valve - spring

[Anglefire]

I've had slightly low oil pressure since installing the new engine - today I decided to fit a new spring (And was slow to rise after the initial start) - I bought a couple of new ones last year of different poundage to fit in the old engine.

Took the one out of the old engine and compared the spring with the "new one" and seemed very similar - took the one out of my new engine and is similar - but about 1/4" shorter 

So fitted the new one (out of the bag) - started her up and the oil light went out straight away (its been stood for a month I would think) though did come back on briefly - but the gauge was rising nicely and then went out. Slight rev and the pressure then rose to around 90psi - before it would get to about 60 on startup and a good few seconds with the pressure low and the oil light on (But no rattles from the engine)

Let it idle whilst i checked for leaks and the like and after a few minutes was happily sitting at 25psi at idle. Before it was 10 after the same sort of time. I've not driven it in anger yet, but hope to later on.

What sort of pressure should I be seeing?

And what length should the springs be?

 

[Pete Lewis]

there is only one triumph spec for all 4 cyl and 6 cyl  

40 -60psi  at 2000 rpm  hot 

there are no other test figures that i know of.

pete

[Anglefire]

Thanks Pete.  

Well, that's good cos I've just been out for a spin around the block and is running as nice as it has for a long time (Even SWMBO said that!) and the pressure is just over 50psi - probably 55 from 2k onwards as far as I could tell. Is a bit of a jump when letting it drop back to idle - I guess the relief valve closing. But idles at a steady 25psi.

24.5'C outside at the moment and the engine temperature was constantly smack in the middle of the gauge. 

I think its running very slightly rich - but can sort that I'm sure - I have a good selection of needles to try, though I will adjust the current set up first.

[dougbgt6]

There are two springs standard and uprated, the same for 4 pot & 6 pot. Standard has 17 turns (?) uprated 20 (?) Presumably uprated is longer (?) Not sure why you need uprated, slip it in before you sell the car? 

On firmer ground my start up oil pressure is 90lbs, hot running 60 to 40. I used to worry, but I think it's the gauge, the thing with gauges is only worry if slowly gets worse.

Doug

[dave.vitesse]

When you see the cold oil pressure at 90 psi on the gauge it makes the old blood pressure rise a bit. But I have never had any problems, with the car that is! 

Dave 

[Anglefire]

18 minutes ago, dougbgt6 said:

There are two springs standard and uprated, the same for 4 pot & 6 pot. Standard has 17 turns (?) uprated 20 (?) Presumably uprated is longer (?) Not sure why you need uprated, slip it in before you sell the car? 

On firmer ground my start up oil pressure is 90lbs, hot running 60 to 40. I used to worry, but I think it's the gauge, the thing with gauges is only worry if slowly gets worse.

Doug

Dunno about the number of turns - though I can look as I have both still, though one is in the old engine to fill the hole and not lose anything!

As mine is running to "spec" I'm not going to worry TBH

3 minutes ago, dave.vitesse said:

When you see the cold oil pressure at 90 psi on the gauge it makes the old blood pressure rise a bit. But I have never had any problems, with the car that is! 

Dave 

Startup pressure - soon dropped back - only took a few minutes.  Not worried. 

 

[Pete Lewis]

easy to be fooled by needles , all have pretty much the first even 2 section set for idle , so even with very wrong needles 

you can set up a wonderful idle mixture but when the piston rises and the taper takes over the running can be very different to 

what your brain is saying

if its not modified then stick with what triumph specified and it does as it should 

when you play with primaries and filters and compression then youre in the land of hope and prayer

which is where a rolling road and emission read out gets it  correct.

Pete

 

[Anglefire]

Yeah I know Pete - they are Roger's old carbs needled to suit his car - which is similar to mine in that I have 4-2-1 stainless exhaust, PH1 cam, stub stack and K&N filters. 

But it won't be the same as Rogers but is close I think. exhaust is a little blacker than I would expect - but then its not sooty - so is close.

[Guest]

Mark,

I take it you are using 20W/50 oil ??

Last year I tried some Penrite20W/60, in the Vitesse, just out of interest to see what difference it made to the oil pressure reading when cold.

It was as Dave said, somewhat disconcerting to see the pressure reading in the region of 90 for some time; needless to say it was changed very quickly back to decent 20W/50 !!

It can be quite surprising to see the difference various viscosities can create.

Regards.

Richard.

[Anglefire]

Yes 20/50 - Castrol GTX from memory.

I have bought some Millers Oils Classic Pistoneeze 20W-50 in preparation for the next change - though will probably be a little while yet as I need to get some miles on the engine! 

[68vitesse]

Been using Penrite 20/60 in my Vitesse 2L MK1 for some years at suggestion of one of the parts suppliers though they are mainly TR.

Regards

Paul

[Anglefire]

16 hours ago, Pete Lewis said:

there is only one triumph spec for all 4 cyl and 6 cyl  

40 -60psi  at 2000 rpm  hot 

there are no other test figures that i know of.

pete

As the wife is on the main computer, I was looking at the Haynes manual at the 1500 engine section - and as well as the normal running pressure, it also specifies the oil pressure relief valve pressure - which is 53psi. A figure not mentioned for the smaller capacity engines. 

Edited May 7, 2018 by Anglefire
Added picture

[NonMember]

11 hours ago, Anglefire said:

Yes 20/50 - Castrol GTX from memory.

I have bought some Millers Oils Classic Pistoneeze 20W-50 in preparation for the next change - though will probably be a little while yet as I need to get some miles on the engine! 

Admittedly I haven't tried it recently but I always found Castrol GTX too thin for the Triumphs. The original Duckhams was good but the new stuff seems less so. I did run Penrite in the PI and Toledo (which were both "well used" engines) but on the GT6 the cold pressure is too high, so that gets Millers. I think the Vitesse has the thinner Penrite in at the moment, which seems to suit her.