oil warning light

winkle · Post by **winkle** » Wed Jul 08, 2009 2:09 pm

Hi all,

Its been a while since my last post but I could do with some advice if possible.

I am sure most of you will give the same answer to this but it has got me scratching my head!

My sump is well baffled (so i thought) but using my car on a circuit the past two times the oil pressure has dropped to nil and the warning light has come on for about 1 second. Before i have had a chance to switch it off the pressure has returned.

It happens in roughly the same place on the track, up the hill towards a hairpin.

After the first time i dropped the sump off and checked the main and big end bearings they were fine!? Took the opportunity to put even more baffling in the sump. Last time out same thing happened.

Obviously you would think the oil is surging towards the back of the sump but i have a trap door and baffle right across towards the rear to mimimise this and the pick up is housed in a box with trap doors. Its a pre-serp 3.9, remote oil filter, cooler, I use 20/50 oil.
It didnt happen the first couple of times i used the car and doesnt happen under hard cornering or braking?

Could it be worn pump gears, air lock, or just oil surge still. Any ideas?

Maybe not dry sumping but using an external pump might cure it?

ian.stewart · Post by **ian.stewart** » Wed Jul 08, 2009 4:00 pm

TBH it des sound like surge, Paddock up to Druids?? How close is the Pickup to the base of the sump, I normally run the pickup as close as feasable to the bottom of the sump, I make sure the pickup cannot be flattened to the bottom of the sump by brazing 3, 5mm nuts to the rim of the strainer which offers about 5mm max clearance.
Baffles, you can fit as many baffles in a sump you want, but if they are incorrectly placed they are not worth the effort, got any pics of the baffles, trap doors are normally placed Left and Right wings and to fron and back if there is enough space, opening towards the pickup, with all compartments made individual to each other, but for a small ability provided to allow for the sump level to ballance its self, I also have a flat plate accross the well with just enough space to allow the pickup to fit thru and a 4"dia tube above the pickup to ensure all oil returns to above and around the pickup which due to a lack of forsight I had to trim back a bit more than I wanted.

Another thought could be the releif valve sticking in the pump, which is a common fault which can easily be sorted by fitting a Tadpole releif valve, and possibly converting it to adjustable rate, both should be available from Real Steel,

CastleMGBV8 · Post by **CastleMGBV8** » Wed Jul 08, 2009 4:39 pm

Hi Steve,

from memory you have a 4.6 engine, are you sure you have the right combination of sump, pick up/strainer and dipstick.

Just thinking that if you've mixed parts, your oil level could be lower than you think and the strainer could be too high in the sump aggravating the starvation you are describing.

Hows the racing going?

Kevin.

Darkspeed · Post by **Darkspeed** » Wed Jul 08, 2009 4:46 pm

Get some assumptions out of the way

1. Oil levels are all correct
2. The Oil light corresponds with the oil pressure gauge
3. No other changes or additions to the oil system - cooler filter etc.
4. No new dents in the sump
5. No change in the oil pressure otherwise

You dont say if you are on a trailing throttle braking or accelerating

Possibilities -

1. It was always doing this and its only now that you notice it as the engine is getting older and the oil pressure is not as good as it was

2. needs confirmation of assumptions above.

Andrew

winkle · Post by **winkle** » Wed Jul 08, 2009 5:37 pm

Thanks for replies guys.

It didnt happen at brands and i did use it there, this is at Lydden. The pickup is 3 mm from the base of the sump and there are no dents. Hadnt thought about the relief valve!

will try to get some pics up soon but these will be before i added more baffles. It has a gulley that collects oil from the gallery and pours it into the box around the pickup.

Kevin, hope you are well. The engine is 3.9 and dipstick etc are all standard parts. Enjoying the racing its just things like this make me think my engine is soon going to lunch itself

The light and guage correspond due to the gauge being mechanical. It does have an oil cooler and remote filter but the pressure hasnt changed other than when this occurs. It happens under acceleration up the hill.

Cheers

Steve

CastleMGBV8 · Post by **CastleMGBV8** » Thu Jul 09, 2009 6:53 pm

Steve,

This is the thread relating to Yeller Terra roller rockers excess oiling and the baffle problem that iI mentioned on the phone.

http://www.v8forum.co.uk/forum/viewtopi ... 8&start=15

Kevin