Peter
1 posts
Joined: 14/06/2006 13:41:06
Location: TUNBRIDGE WELLS United Kingdom (Excluding channel Islands)
Oil pressure relief valve
Clicky
My car is (soon to be) fitted with an engine from a 1987 MG Metro, which I am currently rebuilding. I need a new pressure relief valve anyway, so a couple of questions:
1. Will the pressure relief valve on the search page above fit the engine?
2. Are the ball ones any good? As they are cheaper and apparently quite good I'm quite tempted. Has anyone tried them?
Posted: Jun 14, 2006 01:55 PM
Tim
1850 posts
Joined: 18/10/2004 09:40:59
Location: Bournemouth United Kingdom (Excluding channel Islands)
I've never used the ball-type valve, and I've no idea if it would fit your metro engine, but I'd be worried about fitting it because, unlike the original type, there's no way of getting it out if it gets stuck!
Posted: Jun 14, 2006 04:53 PM
T. Perks
33 posts
Joined: 08/01/2005 20:13:32
Location: chipping sodbury United Kingdom (Excluding channel Islands)
The ball valves are ok but you will need to shorten the spring or you'll get about 90 psi oil pressure, way too much!, the ball do not tend to stick as they are smaller than the original valves and only touch where the chamfer is on the inside of the seat in the engine you can also use the ball from the outer cv joints which are 9/16" i belive. hope this helps.
Oh by the way it will fit as long as your running an A series Engine.
Posted: Jun 14, 2006 07:05 PM
Leebex
Joined: 02/01/2011 21:25:39
Location: Chesterfield United Kingdom (Excluding channel Islands)
Hi, I have a 1985 mini with the 998 engine. I recently replaced the oil pressure relief valve with the ball and spring kit from minispares. my question is, should it have been quite difficult to fit? what I mean is that I had to push with quite a bit of pressure to compress the spring whilst starting the nut. the orange light has gone off on the dash but the car has no oil pressure gauge so want to make sure its ok.
Posted: Mar 01, 2017 11:50 AM
minimans
Joined: 21/03/2017 00:07:43
Location: Sonoma United States
You really need check the oil pressure with a mechanical gauge. just because the light is out does not mean the pressure is OK
Posted: Mar 21, 2017 12:21 AM
croc7
Joined: 13/09/2004 18:16:02
Location: Tacoma United States
I don't know what the spring rate is for that particular kit or the length of the spring for that matter but keep in mind that using a ball in place of the stock plunger (bullet) adds about .25" overall length and will be more difficult to install.
Posted: Apr 12, 2017 06:40 PM
Aldo Guerrini
4 posts
Joined: 15/11/2008 01:36:02
Location: Ravenna Italy
well i had the spring+ball oil pressure on a 1275 spi overhauled engine and the oil pressure was very high (more than 100lbs/ft @ cold engine) ! turned back to spring and plunger original kit and got acceptable values (65-70lbs/ft @cold and 55-60 @ warmed engine) In my opinion and I am not very skilled is not a very difficoult operation to carry out ... believe me if i made the grade you cn do as well ....
Posted: Jun 30, 2017 04:19 PM
J. Clarke
1948 posts
Joined: 28/05/2006 16:49:46
Location: cambridge United Kingdom (Excluding channel Islands)
oil pressure?
yeah bit high wont do any harm tho apart from make it bit more prone to oil leaks. the oil is pumped at high pressure and then a releaf valve stops pressure getting too high. it may just be that either its fitted with ajjustable oil pressure releaf valve and its set high or its been fitted with stiffer oil pressure releaf valve like used in cooper s one or maybe releaf valve stuck, there is bullet shaped bit that is often replaced with ball bearing for this reason. 55-75psi would be more sensible level but i wouldnt worry about it better high than low. you could buy ajjustable oil pressure releaf valve for it prob best solution.
Posted: May 25, 2008 02:13 PM
No oil pressure on rebuilt engine...
Sorry, I didn't read your post properly. Have you actually got oil pumping out of the pressure relief valve hole when you turn the engine over?
Posted: Feb 20, 2008 12:22 PM
Barry Brown
511 posts
Joined: 23/06/2008 12:08:31
Location: New Barn United Kingdom (Excluding channel Islands)
no oil pressure
and check that the oil pressure relief valve isn't stuck open while you've got the oil pipe of the block.
Posted: Feb 15, 2011 09:35 AM
oil pressure
And if that's not the issue when did you last clean out the oil pressure relief valve?
Posted: Jan 09, 2014 09:01 AM
Gavin
20 posts
Joined: 16/09/2004 08:47:07
Location: Ashford United Kingdom (Excluding channel Islands)
Oil Pressure
I had the same problem with my 1293. Turned out to be a worn oil pump. Fitted a Turbo pump, and has run at about 50 PSI ever since (30 PSI after a good thrashing). I too had checked everything, changing pressure reilef valves, filters, oil, and ended up on the pump. Long winded, and really hacks you off, as you need to change the oil and filter yet again to do the pump! You can change an oil pump in three or four hours, if you have a good temperment, (little bit tight in the engine bay!). I managed to do it with the engine still in the car, although it was a squeeze. One other thought though. I HIGHLY recommend that you remove the pressure relief valve spring and cap and replace the cap with one of the ball bearings from a CV joint (fits perfect). This will prevent it from sticking period.
Posted: Dec 08, 2004 01:25 PM
Roger
17 posts
Joined: 07/02/2006 13:05:05
Location: March United Kingdom (Excluding channel Islands)
1275 auto what needle?
While you had the head off I take it you checked the valves and guides. wear in the guides will cause you all sorts of grief. I have recently renewed mine. If you have a vacuum gauge and the needle goes ballistic at idle and smooths out the higher the revs--classic valve guide wear. Also, if the cylinder pressure you quote are correct then try this but don't start the car in the garage afterwards. Remove the plugs and put a little thickish oil in each cylinder, enough to go around the piston then take another set of pressure readings, if the two low cylinders increase then you have piston ring problems. The oil will temporarily fill the gap even under test pressure.
When you start the car after this test make sure you are in the open, it may not fire properly first time but keep at it you will eventually burn all the oil out of the bores. and don't be concerned of the smoke, there will be plenty but it soon clears.
Nearly forgot your first question. I fitted a 1.3 metro auto unit complete , used the metro manifold but RC40 exhaust I also kept the metro carb. After doing the valves and guides goes really well..
Posted: Mar 31, 2008 06:29 PM
OIL PRESSURE DROP
Oh dear, that's way too low. Has it just started doing this or is it a gradual thing that's come on over time? Have you changed the oil and filter recently? Are you using the right oil - it must be 20w50 mineral oil, nothing else. It won't hurt to change the ball and spring pressure relief valve but if that doesn't do the trick you could be looking at new bearings and/or oil pressure pump
Posted: Aug 22, 2011 09:07 AM
92 auto 1275 low compression
Low compression can be caused by leaky valves too, but the way to be sure is to squirt some engine oil into each cylinder immediately before testing. If the pressure goes up then it confirms that it's the rings and/or bores. If the pressure doesn't go up, it's more likely the valves leaking. But the most likely scenario on an old engine is a combination of both!
Posted: Mar 05, 2014 07:38 AM
mini90
32 posts
Joined: 30/09/2004 16:35:30
Location: Nottingham United Kingdom (Excluding channel Islands)
..
Id agree check out the pressure relief valve first. You can change the pump without taking the engie out of the car but its a lot easier to lift the lump. Remove clutch and flywheel then remove Flywheel housing oil pump is located top left behind the housing.
Posted: Jan 04, 2005 08:17 PM
Mk1 Cooper - Emmissions control thing? Can I get rid of it??
That's a bog-standard crankcase breather. I believe it's supposed to prevent excess pressure in the crankcase, which in turn can lead to oil leaks, and so it sucks the fumes back into the intake manifold, via that round thing which is simply a filter (though it may have a valve in as well in case of backfiring). I'm no expert on this but I would leave it alone! Just clean the filter occasionally.
Posted: Aug 16, 2006 11:01 AM
You are supposed to prime the oil pump before turing over - try removing the oil pressure relief valve and pumping oil down the hole (I use a little oil can with a long spout).
Posted: Feb 20, 2008 10:43 AM
J. Carter
Joined: 20/09/2004 12:34:11
Location: Acworth United States
auto block
Phil - go to www.austinamericausa.com and under the articles you will find instructions on converting an auto block to manual. Basically, you will need an adaptor plate, pressure relief valve seat for manual (or remove the auto one and weld up the two holes), drill the oil hole for the dipstick, and the oilway for the manual pump. Yes, the oil way is different in that they did not finish the drilling.
Posted: Oct 12, 2008 09:52 PM
jag_clarke
could be pressure releaf valve sticking open at low pressures maybe. might be worth replacing it with ball bearing type if it hasnt already, standard type can stick from metal filing in oil. i wouldnt of thought it would help having ajjuster as it shouldnt be opening until 60psi anyway which is fine. at least u know that engine isnt being damaged but as u say if your used to 60psi at low rpm does suggest something changed.
Posted: Nov 24, 2008 10:26 PM