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Re: High Oil Pressure
Posted: Thu Aug 04, 2022 3:13 pm
by SuperV8
richardpope50 wrote: ↑Tue Jul 12, 2022 11:41 am
Normally my RV8 (from TVR Griffiths 500) runs circa 30psi. Water temp runs 85 - 90 and rarely exceeds that as fan brings temp back very quickly.
Yesterday as a birthday treat for my son he had an IAM Skills Day at Thruxton. It was hot (obviously) and when on the track he once thought the water temp hit 120c. OK, my car was the fastest there! He did not really notoce the gauges anyway as concentrating! On the last lap we think there was a small splat of water from the header tank that hit the windscreen. (Did do once many years ago when I had a blocked rad.) I thus assume water pressure caused this but not no signs of any escape of water anywhere. Oil temp was showing 90c which is hotter than normal which is circa 80c
At the end of the last session I drove home but on starting I immediately noticed oil pressure was 60psi. All else seemed fine but drove slowly. Oil pressure stayed around 60psi for a few miles and then on A303 at 50mph it came down a bit then fluctuated between 30psi (normal) and 60psi. Kept going as all seemed OK and within 20 mins psi stayed more often at 30 but short periods at 50. After about 45 minutes psi was normal at 30. the rest of the journey the psi stayed at 30. water temp was normal all the way home at 85 - 90c.
Any ideas why pressure so high?
Just found this oil pressure spec in the workshop manual for pre 99 (GEMS) and post 99 (Thor) engines.
How does your oil pressure compare?
Interesting the Thor has a higher pressure - at a lower rpm. Checked early and later service manuals and both quote a 60mm pressure relief spring length! so I wonder how else they are controlling the oil pressures?
Re: High Oil Pressure
Posted: Sat Sep 03, 2022 3:33 pm
by richardpope50
Thanks all - gosh is it a month since I checked posts, sorry.
Well it has been perfectly OK since I first posted with the gauge showing a stedy circa 30psi. No hint of even slightly high pressure. I've driven a good few miles including a 600 mile trip up to get Dale in Telford to map my MS ECU. MPG now close to 30 instead of 23! Disappointing RR BHP of 243.8 but feeling it could be a worn cam at 50k miles as it is a standard TVR one. Still not going there in forseeable future. Car much improved in smoothness and it just seems better. Dale also changed the injectors for new Bosch ones after testing the original RV8 ones that were not very consistant and did not have much of a spray pattern, more jets.
As for PRV valve, I may have another look this winter but t is just so difficult to find it (in my Dax) let alone get it out and more importantly back in.
Appreciate all answers.
Re: High Oil Pressure
Posted: Wed Oct 05, 2022 8:14 pm
by phlize
Hi, I'm new to this Forum and indeed new to V8s .
I have a Hawk with a Rover Vitesse V8 installed and today suffered the sticking OPRV!
So I'm here for some help.
The pressure went to the stop on the gauge - 100psi.
I took the screwed cap & spring out of the oil filter/oil pump housing but the valve is stuck in there.
No amount of pulling with a magnet or a hooked tool would remove the valve.
I'm hoping that once it's out I can just polish it with a bit of wet & dry.
Any ideas??
Thanks in advance.
Phil.
Re: High Oil Pressure
Posted: Wed Oct 05, 2022 9:10 pm
by stevieturbo
Any ideas for what ?
Re: High Oil Pressure
Posted: Wed Oct 05, 2022 9:50 pm
by phlize
Any ideas on how to remove the plunger valve??
Cheers
Phil.
Re: High Oil Pressure
Posted: Thu Oct 06, 2022 5:51 pm
by ChrisJC
I would say with difficulty to be honest!
Chris.
Re: High Oil Pressure
Posted: Thu Oct 06, 2022 6:24 pm
by Ian Anderson
Remove king pin lead from distributor so it does not start and crank the engine
Put lots of rags and catch tank underneath and hopefully the oil flow will push it out
Ian
Re: High Oil Pressure
Posted: Thu Oct 06, 2022 8:45 pm
by stevieturbo
phlize wrote: ↑Wed Oct 05, 2022 9:50 pm
Any ideas on how to remove the plunger valve??
Cheers
Phil.
Depends how badly stuck.
make up a blind puller ( or buy one ), heat
Can you not just tap it down with something suitable ? It's pretty easy to see. Heating the housing might make it move a little easier.
Re: High Oil Pressure
Posted: Fri Oct 07, 2022 7:34 am
by ChrisJC
I think the problem is that it's in a blind hole, so you can't push it from behind?
Maybe a grease gun on the port that connects to the back of it, and try to pump it out?
Chris.
Re: High Oil Pressure
Posted: Fri Oct 07, 2022 2:02 pm
by stevieturbo
the plunger is plain to see in the picture. Yes you might not be able to touch the end you likely do not need to.
And it is easy to get a blind puller or make something up to pull it out.
Re: High Oil Pressure
Posted: Fri Oct 28, 2022 7:51 pm
by bigaldart
Compressed air is the best bet, it won't take all that much with no spring behind it. How have you got it stuck closed? Never had that, they always stick open IME.
Re: High Oil Pressure
Posted: Sat Oct 29, 2022 7:18 pm
by phlize
I tried turning the engine over with the coil disconnected but it didn't move.
I was trying to avoid taking it off the engine but working upside down in a confined space limited what I could do.
So in the end I admitted defeat and unbolted it from the engine.
On the bench compressed air didn't move it - the air just escaped from one of the drillings.
I managed to extract it using a piece of wooden dowel rammed in the cavity in the bottom of the plunger.
Eased the bore with some wet & dry - the plunger was unmarked - to the point where it moved relatively easily.
Now back in the engine & oil pressure 40psi cold - fingers crossed it doesn't go much higher on the road test tomorrow.
Thanks for all the suggestions guys,
Phil.
Re: High Oil Pressure
Posted: Sat Oct 29, 2022 8:11 pm
by stevieturbo
It's the only correct thing to have done.
How tight did it feel in the bore ? must have been pretty tight to get stuck like that ? Was the bore itself smooth ?
Re: High Oil Pressure
Posted: Mon Oct 31, 2022 9:19 pm
by GDCobra
May be worth looking into whether you could get someone to hone the bore, better than paper abrasives.
Unfortunately a honing machine is one machine I don't have access to these days.
Re: High Oil Pressure
Posted: Mon Oct 31, 2022 10:32 pm
by stevieturbo
bit of wet n dry works fine for smoothing the bore. Or you can buy DIY small cylinder hones, but they tend to be pretty fragile.