Oil Pressure Relief Valves

[TravellinMan]

Cautionary Tale for those less mechancically minded of us...

 

I've suffered from low oil pressure, at high revs, in my 2litre Zetec.

Took the sump off last week and found it didn't have the Ford baffle plate bolted to the block. replaced this.

thought i'd look at the pressure relief valve as various sources suggested the spring could be defective.

undid the retaining plug and the whole lot fell into my hands. all looked ok so reassembled and returned to its recess.

put sump back on and fired up. Zero oil pressure.

remove sump and prime pump with grease and remove relief valve. look long and hard and replace as appears fine.

put sump back on and fire up. zero oil pressure at tickover, some at medium revs.

remove sump and remove relieve valve. discuss its assembly and try putting the sliding valve part the other way round.

replace sump and fire up. zero oil pressure.

buy new pump from Ford.

check how new pump is assembled and find that the pressure relief valve is the OPPOSITE WAY ROUND!!!!

Even two different Haynes manuals show the order as being threaded plug, then spring, then sliding valve.

Actually it's threaded plug, sliding valve, then spring.

 

Keep your eyes peeled when removing spring loaded parts, even if the spring isn't under that much tension/compression.

If your working under the engine and have just removed the sump wait the oil to stop dripping and give it a good dry with a rag so you can look up at what you're working on while your removing the offending article.

 

This should help reduce the number of times you need to remove the sump!

 

Travellin' Man

Tony Boyd

97,000 miles in 6 years!

[julians]

took me 4 days or scratching my head to work that one out when it happened to me. I checked and double checked it against the picture in the haynes manual several times, tried everything I could think of to try and get pressure. Eventually I just turned it the other way round out of pure frustration and last resort'ness, and it worked.

 

 

 

 

[J.R.]

Been there, done that, evening before race day! unbeleivable how long car ran without oil pressure (until sussed it) without damage.

 

Eventually even after getting valve the right way round pump wouldnt prime (been run dry for very long time) - had to tip car on side to pour oil through filter gallery!