What are the causes of 15/20lbs of oil pressure???

[zekow1]

That's pretty much it ,What are all the possible reasons for low that is 15/20Lbs if oil pressure???
Apart from ? Your engine is dead dude.

Nope it's still not running yet,Maybe next week???

[Marko]

start from the source of the pressure and work your way around.

at what revs is that pressure?

manual states that oil warning light switches on at 3-5 PSi

in what condition is you oil pumop ? you have required tolerances in workshop manual. Pressure generated by the oil pump is regulated by oil pressure relive valve. Is it in proper condition? any leaks?

and in what condition are your bearings? since worn bearings (or wrong tollerances) manifest themselves as low oil pressure

[bmcecosse]

Hmm - is this with the engine hot and at decent revs - or when idling ??
Could be - hopeless gauge/low oil level/oil horribly contaminated with petrol(leaking fuel pump diaphragm)/stuck relief valve/horribly worn oil pump/ruined engine....
Pretty much in the ascending order of ghastliness I'm afraid.

[Beans]

... BMC beat me by a minute and Marko by two [:p]

<center>
<font color="blue"><i>1980 TR7 DHC (my first car, now restored and back on the road)
1981 TR7 FHC Sprint (better known as 't Kreng)</font id="blue">
<b>[url="http://www.tr7beans.blogspot.com/"]<u><b><font size="2"><font color="red">My Weblog</font id="red"></font id="size2"></b></u>[/url]</b></i></center>

[PeterTR7V8]

I can't tell what engine is in your picture but for any motor if that is your oil pressure at idle when warmed up then it is normal. Rover V8s tend to vary widely as to pressure at revs because they are loose old tarts but a rough guide is 10psi per 1000RPM up untill the point where the relief valve opens which shouldn't be much less than 40ish. My motor is recently rebuilt & only goes up about 38psi. The 2L motor has a higher pressure I believe. The first thing I'd check for is an oil relief valve sticking that is sticking open.



The map: http://tinyurl.com/wedgemap . The blog: http://www.forum.triumphtr7.com/topic.asp?TOPIC_ID=8548

[Beans]

My fairly trashed Sprint has an oil pressure @ idle (± 900 rpm) of somewhere between 40 and 45 Psi when on temperature.

What oil (grade) are you using?

<center>
<font color="blue"><i>1980 TR7 DHC (my first car, now restored and back on the road)
1981 TR7 FHC Sprint (better known as 't Kreng)</font id="blue">
<b>[url="http://www.tr7beans.blogspot.com/"]<u><b><font size="2"><font color="red">My Weblog</font id="red"></font id="size2"></b></u>[/url]</b></i></center>

[zekow1]

Thank you for givin other alternatives other than "Its caput"
I will try to answer in the best of my abilities.

I have used a new pressure gauge to see if the old one was OK and it was the same.

The oil is 20/50 I am in florida usa.
The oil has 5 miles and the filter Toooo.

the pressure 15/20 is at idle and if I rev it goes down slightly.

It does over head fast.

it knocks slightly

Fuel pump good no leaks

new oil pressure switch

Fuel tank and new fuel changed and cleaned.

No leaks anywhere.

? oil relief valve I will check?

? Oil pump I will also check?




Nope!! it's still not running ,Maybe next week???

[Bobbieslandy]

<blockquote id="quote"><font size="1" face="Century Gothic, Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">My fairly trashed Sprint has an oil pressure @ idle (± 900 rpm) of somewhere between 40 and 45 Psi when on temperature<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">

Admitedly i haven't used another gauge, i'm not sure if mine is working correctly even though it is virtually new (3months old) but...

9psi @ 850rpm
15psi @ 1000rpm
40psi @ 1900rpm
48 - 49psi @ 4000rpm to redline.

This is a 0 - 100psi TIM oil pressure gauge, i'm not sure of their accuracy. According to Jigsaw racing, 15psi at idle and 45 - 50psi in the higher rev range is normal when hot.

Just to add, this is with new mains and big ends but the original oil pump and relief valve.

[saabfast]

If the pressure drops with an increase in revs it sounds like a very bad relief valve. Even a worn pump should increase the pressure a little with increasing revs.

Alan
Saab 9000 Stg 1
Saab 9000 2.3 FPT Auto
'81 TR7 DHC

[Bobbieslandy]

just had a thought, i don't mean to cause offence as i'm not aware of the situations surrounding your abilities etc but if it's over filled with oil it can aeriate causing a pressure drop as the crank stirrs up the oil. My first move would be to pin-point that knocking, i'd be more concerned about that than the oil pressure.

[zekow1]

Oil is on line

relief valve I have been seaching the books can't find any info on the unit. any help there??

The knocking I will check more carefully

Nope!! it's still not running ,Maybe next week???

[Marsu]

The ROM (available from JClay's site) lists these operations:
12.60.56 - Oil pressure relief valve - remove and refit, page 81
12.60.32 - Oil pump overhaul, page 79
12.60.26 - Oil pump remove and refit, page 78