Oil Pressure question again..

[HVGRIFF430]

Good Morning,

My first post in this group ,but a post that i am a little bit worry about. Bought my second Griff after having one 10 years ago. A 93' 430 Griff LHD . Cold i have at idle 25psi,at 3000rpm-> 30-35psi.That sounds not bad to me for a preserp engine with 64k miles on it. When hot it has an oil pressure of 9-11 PSI on idle.On 2000-3000rpm it gives 20-25 PSI. Only problem , at idle on 9-11 PSi the yellow warning led flickers and often lightens completely.
Do i have an oil pressure problem? Last owner changed the oil in 2019,but the car just ran 650 miles since then.
it has Kroon Oil 10W-60 in it.

Thanks for your thoughts.

[scottliv]

Morning - your hot oil pressure sounds low. I have a 92 430 and the pressures you give cold are what I generally have hot. The pressure gauge is driven from an analogue sender and the yellow light is a digital switch- so essentially different sources. I have attached a picture showing the 2 sensors but this sounds pump related. The sensor on the left supplies the gauge, with the one on the right supplying the light. There is a relief valve as part of the pump so this may be passing or the pump gear wheels are worn therefore not getting the correct seal.

[HVGRIFF430]

Thank you for your answer. I was planned to measure with mechanical gauge, but what i was afraid of is that there is a problem with the oil pump.. So placing new pump gears is the solution?
is this a hard job?

[scottliv]

It is a fairly easy job, if indeed the pump is the issue. I have had another think and it could be to do with the oil pick up as well. Sometimes this can get blocked, or a crack drawing in air or even the gasket where the pick up fixes. I have seen pictures of the strainer blocked with sealant from the sump gasket.

[Zener]

May be just 650 miles but in 2 years try changing oil and filter 1st it may just be fuel diluted (piss water) due to lack of use , they tend to over-fuel a little on cold start and this may of seen many without proper use

[QBee]

What grade of oil would you recommend for road use, Zener?

[Zener]

Valvoline VR1 10/60 semi syn (not the 20/50 min VR1) but heard some good things about https://drivenracingoil.com

[asd2001]

Without trying to hijack the thread or start a massive debate.... what’s the reason behind 10/60 rather than 20/50? I’ve always used 20/50 VR1 for general running around with no complaints - time for an oil change soon and you’ve got me thinking!
Thanks

[HVGRIFF430]

Can you change the oil pump gears with the engine in the car on my preserp 4.3 engine?
Are the pump gears coming easy out and easy to put back?

I think i have to check them and replace them.

any suggestions which gears to buy where?

Thank you

[scottliv]

Hi yes it is very easy. I would drain the sump and remove the filter. Easiest to work under the car / from front drivers side wheel arch. Need to also remove the distributor. For ease I would put the engine on TDC and align the rotor arm with No1 cylinder. Make sure you mark the orientation of the alternator body.

I would try Racing Green for the parts or you could get the gear wheels else where. They appear to be readily available.

Edited by scottliv on Friday 21st May 22:41

[thicksliced]

A few years ago I had very similar problems with my 4.3. The oil light would flicker at tickover and would light up when I lifted off the throttle and the pressure gauge didn't get above 25psi. A replacement sender cured the oil light problem but the new pressure gauge sender didn't.

I had a mechanical gauge put on and it showed 30 psi at tickover and 54 psi at 4000 rpm both hot.

My gauge now reads 0.

Before you do any thing find out what the oil pressure really is. I bet your gauge is nearly as dodgy as mine is!

[HVGRIFF430]

Have done a test with mechanical gauge now. Pressure readings are 15PSI on idle hot ,35 PSI on Idle Cold.
Are these to low or fine? Strange that the warning light comes up then.
I am thinking of putting an upgrade pressure valve spring and new oil pump gears or should i leave it and try another oil pressure switch?

[Englishman]

HVGRIFF430 said:

Have done a test with mechanical gauge now. Pressure readings are 15PSI on idle hot ,35 PSI on Idle Cold.
Are these to low or fine? Strange that the warning light comes up then.
I am thinking of putting an upgrade pressure valve spring and new oil pump gears or should i leave it and try another oil pressure switch?

Those pressures look fine to me. I would also measure ~2500rpm. Most obvious culprit for the warning light coming on is the sender. I would change that before anything else.

Not TVR specific, but I found this useful http://www.roversd1.nl/sd1web/oil.html

[scottliv]

My warning light only came on when it was hot. I.e. drive the car for a while, then it would work when it was restarted. Got one from eBay for less than a fiver and all is good now.

[HVGRIFF430]

same for me, have to drive some time till the oil is hot.Then the light comes on on idle.
When at 2500 rpm ,the pressure shows between 30-35 PSi hot , cold it goes just over 50 PSI at 2500 rpm.

I will start with the oil pressure switch to start!

[HVGRIFF430]

Hello,

Short question.

Do you have to prime the oil pump after taking the relief valve and spring out?

Thank you

[Englishman]

HVGRIFF430 said:

Hello,

Short question.

Do you have to prime the oil pump after taking the relief valve and spring out?

Thank you

If you have let the oil in the pump drain out then yes. If you put the retaining bolt back (or something else) in as soon as the spring was removed you should be ok as you will only have lost a small amount of oil.

[scottliv]

I bought this. It fits onto the drive of the pump and primes it using a battery drill. I didn’t fancy packing the pump with Vaseline then sending that round the system. Using this was enough to put the yellow warning light off.

https://www.ebay.co.uk/itm/124695636753

[HVGRIFF430]

I assume that the distributor has to be taken out and the tool fits in the shaft?

[Steve_D]

HVGRIFF430 said:

I assume that the distributor has to be taken out and the tool fits in the shaft?

Yes.
If you get good oil pressure when you prime you will know it as it will try to twist the drill out of your hands.

Steve