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xe loss of oil pressure
ned - 18/4/07 at 10:24 AM

Ran the engine up yesterday evening (as I do every now and again to keep it turning over etc). Ran it for about 10mins, it was up to temp (80-85deegrees) and I switched the fan on manually before it cut in automatically. I'd given it a few blips and left it idling, started tidying a few bits up whilst I let it idle.

A minute or two later I started hearing a top end rattling sound, immediately looked at the gauges which were showing near enough 0 oil presure. Turned it off straight away. left it a couple of mins and restarted, same thing so killed it immediately. It was only idling and didn't run for long and under no load, twas only for a few seconds so I'm quite confident about there not being any damage inside, just curious about what might have caused it.

The engine had new bearings throughout when rebuilt, has steel pump gear, external oil filter on take off plate. No leaks anywhere I can see just sounded like oil starvation to top end. The engine ran fine all day on the rolling road and has been run up every now and again in the garage. I've not changed anything at all recently except for the alternator which can't be related.

Not investigated any further but first thought was the oil pressure relief valve or whatever it is that sbd sell a kit to fix.

Was thinking of trying running it up again once it had fully cooled when the oil is thicker and see what happens.

Anyone out there with experience (nsdev/stu16v etc etc) of this engine got any other thoughts?

cheers,

Ned.

[Edited on 18/4/07 by ned]


Mr Whippy - 18/4/07 at 10:30 AM

not good. I think I would check that the shaft for the pump is ok and not rounded and that the pump does turn, you don't say what engine it is. The fact that the engine started to rattle leads me to believe the gauge reading. I would not try to start till it's fixed, what ever it is and once done take out all the plugs and spin it a while on the starter motor to get the oil flowing again. Your lucky it didn't seize.

[Edited on 18/4/07 by Mr Whippy]


ned - 18/4/07 at 10:38 AM

as per the title it's an XE.

It was a second hand oil cover plate and steel pump gear from a guy who owns a vauxhall caterham and has built several vauxhall engines (been out in another caterham with an engine he'd built). I cleaned and checked it when I rebuilt the engine but never had the relief valve out so this seems to be the main culprit as I know martthefridgeman had one stick on his motor and had to do the same fix.

http://www.sbdev.co.uk/Dry_Sump_Systems/Oil_Pump/Oil%20pump.gif

http://www.sbdev.co.uk/Info_sheets/Oil_systems/nylon_relief_valve_kit.gif

ps running the westfield ally sump and pickup pipe.

[Edited on 18/4/07 by ned]


Mr Whippy - 18/4/07 at 10:51 AM

ah a bike engine, not to clued up with all those, I actually thought that was short for 'extreme' loss of oil pressure well it lunch time and I'm starving
Looks like you have the cultrate just be glad it didn't happen when you were out on the road.



[Edited on 18/4/07 by Mr Whippy]


hobbsy - 18/4/07 at 11:10 AM

Its not a bike engine, its a Vauxhall XE, 2 litre car engine. As found in lots of things like Calibra's, Astra GSI's etc


b184 - 18/4/07 at 11:26 AM

A bit of a daft question, what dose the oil dip stick say, is ther oil in there?
oil pressure should be 1.5 bar at 850rpm.
i would be tempted to remove plugs, dissconect injector wires to prevent fuel injection and possible cylinder wash.
do an oil pressure test, wet & dry compression test also.
comression should be 12-15 bar


NS Dev - 18/4/07 at 11:44 AM

Hi Ned, DOH!!!

Are you running wet or dry sump ( I know its std oil pump but was wondering about oil levels)

If its wet sump, is it caterham or sbd/qed type one?

If its caterham, you have to run 10mm above the gm spec oil level to get decent pressure.

I would guess at the pressure relief valve. undo the nut and extract it, then polish it up with 1200 then 1500 grit wet and dry, then with brasso. blow out the tube it sits in then try it again.

As you say, no damage should have resulted.

The oil pump can wear and spin on the crank flats, but I'm guessing you've built it and know its ok in that dept (as long as the crank centre bolt is tight it will be fine)

Don't go to the nylon relief valve, they stick just as much as the stock ones, better to polish up thestock one


Mr Whippy - 18/4/07 at 12:03 PM

quote:
Originally posted by hobbsy
Its not a bike engine, its a Vauxhall XE, 2 litre car engine. As found in lots of things like Calibra's, Astra GSI's etc



ah well if it's newer than a pinto then I haven't a clue, weird colour that cast iron, very light gray


ned - 18/4/07 at 12:09 PM

It is the ally cast westfield wet sump (same as sbd etc sell, 100mm deep).

I think I need to remove and inspect the relief valve and give it a clean up as you mention Nat. I will check the crank bolt but it was done up pretty tight and pulled up against the key. I wouldn't expect that to go anywhere at idle!

I think I'll also drain the oil out, measure it and confirm with westfield what quantity they fill it to. I recall I put in best part of 4.5-5 ltrs but better safe than sorry i suppose by double checking it.

cheers,

Ned


MkIndy7 - 18/4/07 at 05:36 PM

My XE in the Tin-top has sounded a bit rattely when its run close to the minimum level on the dip stick, and that was from cold.
(I know legend has it there a bit rattely from cold but mines never sounded like that before)

That was also running without the extra capacity of the oil cooler as well, thats about to go back on for the sunner because i've seen the Digi Dash indicator go down to 1/2 pressure when warm without it! (Does anybody know if thats normal as there's no Measurement of pressure just a bar graph)


david walker - 18/4/07 at 07:54 PM

Given that you run it regularly and it's not been a problem before isn't it unlikely to be a sump design issue or insufficient oil?

It'll be the pressure relief valve, fairly common problem of course with Vauxhalls after rebuild. What you should have done is revved the engine up and watched the oil pressure gauge. Whenever the relief valve is sticking the gauge works like a rev counter!

Incidentally why do people fit steel pump gears? - and before some nob like Mr Whippy answers, I build dozens of competition Vauxhall engines every year and am always very weary of new oil pump casings, plastic relief valves and steel gears. Whenever I had pump problems in the past, one of these three items were in use.

[Edited on 18/4/07 by david walker]


NS Dev - 18/4/07 at 08:17 PM

LOL Dave we had the same trouble with my mates rally car too.

All the "recommendations" said use the nylon valve and steel inner gear......well the gear wasn't the right thickness for the casing, if we had put it in and run it that would have been curtains for the pump, and the nylon valve stuck loads, put the std one back in (polished up) and it was fine.

Since then neither of us have run anything other than std bits, and ok, we're not revving them to over 8000, but they work fine up to that in my experience.

Ps Dave my only point on the sump was that the caterham one is stupidy sensitive to level changes (i.e. it doesn't hold enough oil!!! ) and even 0.3 litres down will drop the pressure, dunno why, could be the foam baffle and lack of "head of oil" to push it to the pickup, no idea, but mine seems none too brill and will be collecting dry sump bits asap!!!

[Edited on 18/4/07 by NS Dev]


ned - 18/4/07 at 08:33 PM

Thanks for the input guys, now you mention it the oil pressure gauge did move a fair bit when you revved the engine up so confirms relief valve i guess.

thanks again.

Ned.


Stu16v - 18/4/07 at 08:59 PM

Thirded NSdev/David Walker - the relief valve

Polish it up (wet and dry, and a bit of patience) and bung it back in, after giving the housing a good claen up too.

I (and others) used to run the Westfield sump with the oil level at the bottom of the M of 'Max' on the dipstick. Didnt effect oil pressure during 'normal' use, but prevented surge during hard braking.


Stu16v - 18/4/07 at 09:01 PM

P.s. Running it up for 10/20 mins at a time is actually a lot worse than storing it *properly*, and not running it until you actually come to use it...