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Oil Additive - yes or no?
RazMan - 9/9/07 at 12:46 PM

I recently changed the oil in my Duratec to fully synthetic 5W30 as recommended in the Haynes manual. Initially I was getting good oil pressure (2 bar at tickover & 5 bar cruising) but over 500 miles the the pressure has been slowly coming down and now I am getting the oil light coming on at tickover (less than 0.7 bar)

Question - Should I change the oil to something a bit thicker (10W40?) or bung in an oil additive and see if that improves the pressures until the next oil change?

takumi - 9/9/07 at 02:00 PM

You need to discover what is causing your drop in pressure.. Otherwiser it might just keep getting worse..

britishtrident - 9/9/07 at 02:05 PM

Don't put oil additive near it, either the low oil pressure has a mechanical cause or you are getting oil dilution from an over rich mixture.

First step is to drain the sump and try some fresh 5W/30, if the problem is oil dilution the pressurewill perk up.

[Edited on 9/9/07 by britishtrident]

britishtrident - 9/9/07 at 02:11 PM

I should add oil pressure in itself isn't that important, but oil flow is important.

However a drop in oil pressure is symptom something else is wrong.

RazMan - 9/9/07 at 03:31 PM

Oil dilution? The mixture is certainly a little on the rich side but as I'm still getting over 30mpg I don't think its bad enough to dilute the oil in 500 miles .... or is it? Is there any way to test the sump oil to see if dilution is happening?

I used to use 10W40 and that certainly gave more pressure but I found that tickover was a little low when cold, presumeably because the pump was working harder.

My engine has done about 60K miles now so its no spring chicken, but it is mechanically quiet and doesn't burn any oil. I have heard that fully synthetic oils are best used in new engines - maybe a semi synthetic would be better in a (relatively) high mileage engine.

[Edited on 9-9-07 by RazMan]

mark chandler - 9/9/07 at 06:34 PM

Oils are not all the same, I had a range rover and treated it to comma oil because I was skint, within a couple of weeks followers started to tap, so went back to Millers oil and it was fine so a false economy there ....

Is the brand the same as you used before ?

Regards Mark

[Edited on 9/9/07 by mark chandler]

RazMan - 9/9/07 at 08:30 PM

TBH I only changed to 5W30 after reading a tech sheet on Duratec engines written by Ford. I was originally using 10W40 for the first 6000 miles and had no problems apart from a slow tickover. Perhaps a slow warm up is a small price to pay and I should go back to 10W40.

britishtrident - 10/9/07 at 06:41 AM

5w/30 was speced by Ford to stop the tappet jacking problem silvetop Zetecs had when cold, istr you engine dosen't have hydraulic tappets.

You could try a 5w/40.

britishtrident - 10/9/07 at 07:01 AM

quote:
Originally posted by mark chandler
Oils are not all the same, I had a range rover and treated it to comma oil because I was skint, within a couple of weeks followers started to tap, so went back to Millers oil and it was fine so a false economy there ....

Is the brand the same as you used before ?

Regards Mark

[Edited on 9/9/07 by mark chandler]


Yep engines with hydraulic tappets can very fussy about oil --- they need not only the right viscosity but also large ammounts of anti-varnish and anti-sludge additives.
Use too high a viscosity oil in a GM engine and the hydraulic tappets rattle, but use too high viscosity oil in a Zetec and the hydraulic tappets jack up when cold.

One trick with noisey hydraulic tappets particularly on V8s is to try adding a litre of ATF to the sump oil and running the engine for a day or even two before changing the oil. The ATF is loaded with ant-varnish additive if the tappets have been gummed up they usually quieten down after this treatment.


Don't leave the ATF in too long as it contains sulphur
which in the long term will increase bearing wear.

[Edited on 10/9/07 by britishtrident]

RazMan - 10/9/07 at 09:58 PM

quote:
Originally posted by britishtrident
5w/30 was speced by Ford to stop the tappet jacking problem silvetop Zetecs had when cold, istr you engine dosen't have hydraulic tappets.

You could try a 5w/40.


I think you might have something there. I had a 150 mile trip today and closely monitored the oil pressure.
It was fine on startup (about 2.5bar at tickover) and getting onto the motorway with everything warmed up, going by water temps anyway, nearly 4 bar while cruising at 'enthusiastic' speed. After about 50 miles or so the pressure had dropped to 2 bar cruising and coming off the motorway the oil light was coming on at 0.7 bar and at one point went down to 0.2 bar!

The story was the same on my return trip so I assume the oil is thinning out too much when hot so maybe a 10W40 would counteract this. Alternatively I found some Millers XFS 5w40 on eBay which might be even better.

Interesting, I checked the Ford supplementary manual and they state the following:
... note the remark about 5W30 being only suitable for Northern Europe. Maybe 5W50 synthetic would be best then?

Looking at the oil pressures stated, maybe its not as bad as I thought

[Edited on 10-9-07 by RazMan] Rescued attachment Oil Pressures.jpg
Rescued attachment Oil Pressures.jpg

britishtrident - 11/9/07 at 08:01 AM

Halfrauds do quite a decent 5w/40 fully synth -- recently it was on a bogof -- I got two x 5 litre for 31 quid.

One question that hasn't been asked is Do you have an oil cooler fitted, with a mid engine it is a good idea.

Going back a few years the Series 1 Lotus Espirit had problems with oil temperature that didn't occur with the Elite or éclat so they fitted a cooler in the later models.

[Edited on 11/9/07 by britishtrident]

MikeRJ - 11/9/07 at 08:05 AM

If you want a 5W50 Halford have a "Trackday" full synthetic oil, and they currently have a BOGOF offer on their own brand fully synthetics.

RazMan - 11/9/07 at 08:25 AM

Thanks for the bogof tip - methinks I'll be off to Halfrauds today

Ref oil cooler: I don't have one fitted at the moment and as I want to turbo the engine soon I really need to fit one, although I am not sure where to plumb it in.

RazMan - 11/9/07 at 04:10 PM

Update:

Just went into Halfords and apparently their on-line promotion does not apply to their stores so I've had to order on-line and wait for delivery.
I was under the impression that they had to honour their web prices but apparently not ...... which is a bit frustrating.

Oh and apparently their 'buy one get one free' slogan should read 'buy two and get one refunded' ........ now I remember why I don't buy much from them - still, the trackday oil is a bloomin good price

Angel Acevedo - 11/9/07 at 05:52 PM

I have to ask...
What does it mean?

RazMan - 11/9/07 at 08:08 PM

Aha, yes it's a quaint little English saying isn't it

BOGOF = Buy One Get One Free
Basically it means 'two for the price of one' but us Brits like to put acronyms on everything

I'll bet that you have something similar in Mexico Angel?

[Edited on 11-9-07 by RazMan]

Angel Acevedo - 14/9/07 at 03:02 AM

We have "Dos por Uno" or 2x1
Two for the price of one