oil pressure UPDATE

[Trotsky]

A Quick recap first:

over the winter I decided to address the tappety row that I and others on here were convinced could be sorted.

Car is wet sumped.

I have modded the cam cover as per SBD.

dropped sump and changed Baffle.

new oil filter

Mobil motorsport 15 /50 fully synthetic oil.

and now fill up to about a cm above the max mark on the dipstick.

car was sat for about 2 weeks drained of oil.

 

On getting everything back together I initially had what is usual for mine 2 bar at tickover and 4.5 ish running cold, on my first run out after about 10 miles I spotted gauge reading zero oil pressure luckily just as I was pulling into my garage, how long it had read zero or if it suddenly dropped I dont know as I was blatting with my new Brooklands and was too busy wiping tears out me bleedin goggle less eyes. took off bonnet expecting to see all my new oil everywhere from some forgotten to tighten fitting but all was well and dip stick reading fine.

anyway, later went on blatchat and was advised poss sticking PRV or dodgy oil pressure sender.

pissed about with the sender took wire off and earthed to block, gauge went off the scale with ignition off, general consensus on blatchat that indeed sender had had it.days later I had to move car from garage and on starting I had no oil pressure on tickover but on blipping the throttle saw atiny move ment on gauge, so drove carefully onto rd and got 2 bar pressure rising to 4.5 at @ 4500rpm but when idling 0 to 0.5 bar rising like a rev counter needle with more revs upto about 4.5 bar. I have since done about 100 miles like this and now that things have settled down with oil flowing round the lifters the tappets are indeed much quieter. so i'm thinking ,Okay I have really got good oil pressure its just the sender telling me I havent, i'll get a mechanical oil pressure set up and that will be cushty.......( not got it yet but imminent.

well todays test drive revealed no oil pressure on start up , thats okay i think it will bounce up to pressure once i get going, I drove slowly to warm things up and was listening VERY carefully . the tappets got increasingly noisier and it seemed all where noisey rather than just a couple as per before cam and sump mods. I was just considering turning round and limping home when I suddenly see 4 bar oil pressure and tappets immediately quiten considerably, a short careful run warmed things up and pressure was reading 0 to 0.5 bar at tickover 2 to 2.5 bar @ 3500 rpm. I am now not convinced I have a faulty sender, its readings seem fairly consistant. its doing my nut in especially as its going to be red hot for the next 6 months and ive loads of blats to attend. Any suggestions is it more like sticky PRV than dodgy sender or both? or maybe summat worse?

 

Trotsky N7 HPC Clams and Brooklands

[Willie.]

Could be a restriction in the oil pickup pipe. If it was me, I'd drop the sump for a look to see if there is anything floating about in there...or jammed in the mesh of the pickup pipe.

 

Willie

[Billyboy]

dropped sump and changed Baffle.

 

Have you fitted the Oil pickup correctly 🤔 and was it cleaned out.....

 

Mobil motorsport 15 /50 fully synthetic oil

 

I have always used 5 w 50 fully synthetic Comma oil

 

or dodgy oil pressure sender.

 

I would be inclined to rule that out - as the tappets do not get noisy if the sender is not working correctly

 

I would be inclined to make sure the oil pickup pipe is OK and with NO blockages

 

 

[Billyboy]

Need to type faster

[Trotsky]

pick up pipe was cleaned thoroughly, I did file 4 grooves in about 5mm deep on at end. it had previously been touching the sump.

 

is it possible for the prv to stick/unstick and what would this do to engine, could this cause readings such as i'm getting?

 

Trotsky N7 HPC Clams and Brooklands

[Willie.]

Your cuts were definitely below the gauze/mesh level?

 

How do you know it is not touching again? It sounds very likely that it is. I'd double check. If it is, you might be as well modifying it a bit more permanently. Maybe cut and reweld it to raise it an 8th or so.

 

I brazed three spuds on mine, so that if it did touch, they would touch first, still letting oil flow in. Do not rely on a few small cuts...you need a good amount of flow.

 

Willie

[Trotsky]

MMmm looks like /I'd best drop the sump tomorrow instead of attending the Yorks big Brekky 🙆🏻 oh well best to be safe than sorry eh?

 

Trotsky N7 HPC Clams and Brooklands

[johnnyseven]

when i did mine i replaced the little rubber o-ring that sits at the base of the oil-pick-up pipe where it bolts on, and my pressure is much lower running 15/50 m/sport oil than the 5/40 helix i was using.

[Willie.]

As far as oil is concerned, definitely. I know the general BC consencus is "It's fine, it'll just be the sender", but from my point of view...I'd rather not take the risk.

 

Why risk your engine? Sure, it could be a sender and it could be fine...but if its not...its quite expensive.

 

Willie

[Stationary M25 Traveller]

Are we talking k-series here ? If so, have you drilled the holes in the shelf bit of the sump gasket, to let oil return to the sump ?

 

A cm above max on dipstick ? If a k-series, check with engine hot and running. Should be to the max, not above. On any type of engine, a cm above max sounds a bit suspect ??

 

On the k-series pick-up, done thing is to bash dents in between the pips on the face of the oil pickup to improve oil flow if close to sump.

 

 

[Trotsky]

VX c20xe not k series, heading to the garage to drain and drop sump now.

 

Trotsky N7 HPC Clams and Brooklands

[Willie.]

Not sure what the pickup is like on the VX, but if it pushes up in with a sealing ring around it (Maybe an o-ring) have a look at it, make sure its not pitted, cut or not seated correctly. If you have it out, smear some oil around the seal before re-fitting the pickup.

 

Hope you get it sorted.

 

Willie

[Bio]

The first thing to do is to establish a reliable oil preassure reading. The best way is to fit a mechanical gauge (cost aprox £50.00 - £60.00)

If the reading is low or fluctuating do not drive the car....Try the following...

Remove the oil pressure relief valve plunger (it should slide out smoothly) and check the plunger for scuffing...Polish with metal polish and 1200 grade wet and dry. Also check the condition of the plunger bore in the pump.

When you blip the throttle the oil pressure should rise quickly and then snap back a little as the relief valve cuts in.

The very large foam sump baffle can restrict oil flowing back to the oil pick up pipe evn when new so I have cut mine back to allow the oil to return but still act as a baffle.

Too much overfill of will cause the crank to thrash about and airate the oil reducing oil pressure but not down to zero.

Make sure the pick up pipe O ring is in good condition.

 

Try the mechanical pressure gauge first !

 

John

 

 

[Jason Plato]

your crazy driving the car with doubts over oil pressure. Fix the problem rather than take the advice from internet on a sender that is not even fitted to your engine.

 

Do the above and either fit a replacement mechanical or electric guage. Consider getting a specialist to do this to ensure you have fixed the problem.

 

Your would also be wise to check the condition of your crankshaft bearings to determine if they have been damaged.

 

The cost of checking and replacement senders is nowt compared to the cost of a total engine rebuild.

 

 

 

 

here is my Duratec R .... C7 TOP

Taffia AO