3drRich

Evening all.

Right ive finally managed to get my RS500 track car to the rollers today to be mapped but unfortunately it didn’t get that far and hoping someone might be able to help.

We we had the car running a few months ago for the first time and although a bit lumpy as some sensors needed changing and it needed mapping it was one of the quietest yb’s I’ve ever heard, the oil pressure gauge was reading right (can’t remember what it was but my mate said it was right) and all seemed fine.
Now a few months down the line we took it in today to be mapped and as soon as it fired up it started to tap almost like a stuck lifter (hydraulic lifters) but it wasn’t constant with the engine revs and seemed intermittent (top end noise) we stripped the cam cover off and everything seemed fine, now the oil pressure gauge was stuck on 8bar (max on gauge) and we decided it was a faulty sender but thinking about it the sender came with the gauge brand new.

So my question is would maybe something have happened where the oil pump isn’t working right and maybe starving top end of oil hence the noise or am I talking shite? It’s a very strange intermittent tap/knock from the top end but before I pull it apart I’m hoping there maybe an easy fix.

Any help would be appreciated.

markk

iTrader: (2)

PRV stuck closed?
Pumping lifters open?

smiley

My saph had that same intermittent tapping when cold was sticky lifter

3drRich

Could you elaborate Mark?

3drRich

As we couldn’t really see anything obvious thought it may be a broken valve spring? Would that make an intermittent tapping noise?
It seems to be coming from the back of the head if that helps?

turnover

If spring was broken would tap all the time and be missing idling lumpy

Mark Shead

You haven’t given enough info. Type of parts used make of lifters. When oil pressure is high. What is oil pressure on tick over. Where cams dialled in. Do pistons have valve pockets. How long car was on dyno. Does it have oil cooler. What dyno what fan. Many things can go wrong.

Mark

3drRich

Hi Mark you’ll have to bare with me I’m no expert, not sure on make of lifters, the oil pressure is reading 8bar at all times, cams where dialled in, pistons have valve pockets, it didn’t go on the Dyno As didn’t want to risk any further problems and yes it has an oil cooler. Cheers

3drRich

It seems to be running ok.

Loomer

If the gauge is reading 8 bar with the gauge powered up but engine not running, you have a gauge issue. your best bet is to use a known good mechanical gauge for diagnostics on oil pressure.

3drRich

It’s only reading 8 bar when it’s running.

markk

iTrader: (2)

Pressure relief valve is stuck shut. Pump is just maxing out. Your lifters cannot handle 8 bar pressure they will pump open.

Adam-M

If it has 8 bar of pressure when warm I’d defo be checking the pump

Mark Shead

I won’t be able to make that much pressure on tickover so most likely sensor fault.
Double valve springs can tick intermittent with one broken and still run ok.
The black style lifters are total crap so you need to know more about he spec to find your fault easier.

Mark

3drRich

Where is the pressure relief valve mark?

3drRich

It does have double valve springs and is quite a harsh ticking but seems to be more so when the revs are at idle rather than when the revs are higher?

markk

iTrader: (2)

In the pump.

markk

iTrader: (2)

In the pump

The Youth.

iTrader: (1)

sounds like the car needs a full check over by a cosworth specialist.
surly a car of this type and with what its built for and with the money already invested in it it deserves to be fully checked over properly

Steve

3drRich

You are right and ultimately it will be but it’s just annoying as it was fine and nothing has changed since the last time it was run and wondered if it was something simple.

The Youth.

iTrader: (1)

If as you say it was running ok then now isn't then yes your right its probably something simple, which a cosworth specialist will no doubt find quickly where as a non cosworth specialist or the internet has 2 hands tied behind there back

Steve

2Litre

Had double valve springs on mine, one of the inner springs failed but car ran fine until higher rpm when the valve bounced.


Tim

COLEYST200

iTrader: (3)

So wot was the out come of the problem then as I would of thought you have resolved it by now .

Was the sound the dipstick rubbing the crank / have you got a WRC breather tank on the motor

3drRich

Sorry forgot to update this. Well it was the small end bearing on cylinder 1 and on closer inspection there was partial detonation to the piston on cylinder 1 so we made the decision to go a more modern spec with a full rebuild and new turbo setup.



The engine is all back in now and was due to go back to the tuners last Thursday for the new management and rolling road session but for obvious reasons that didn’t happen which is a shame as I’m desperate to get out in it now.

Mark Shead

did you find the oil pressure problem and why it had dett damage.

Mark

3drRich

Hi Mark.

It looked like the oil pickup was very dirty so Not really sure to be honest as once we opened it up it was decided very quickly I wanted it rebuilt.

My own fault really as I bought I 500bhp carbon fibre puma (sure you know the car) for its running gear on the understanding that it was built by a reputable guy bla bla bla and sure enough it had the right bits but certainly wasn’t built by anyone reputable. On the plus side it has an original 200 block that’s never been bored and i broke the car so the guts of the engine which is what was basically left owed me about right so I was lucky in that respect but I did think of it that way when I bought the car.