Subaru EJ252 SOHC loss of oil

[stubbie]

Damn I think I have a nightmare developing....

I have an EJ25 SOHC engine installed in my van that appears to be using an excessive amount of oil. The engine has covered aprox 2000 miles since installation and has used 1.5 - 2 litres of oil. I regularly top up the oil and always check the level when the engine is cold and before you ask I do this on a flat service. The exhaust gasses look clean, no blue smoke. The engine doesn't have any external leaks, apart from a tiny amount (smear) of oil that is escaping from the rocker covers onto the HT plug connectors. The engine sounds fine and has plenty of power, at tickover you can hardly hear it running. On a cold morning on startup there is a very slight tapping (piston slap?) but that quickly disapears within a few seconds. I have been monitoring the coolant level and that has remained steady, no oil in coolant and no overheating problems.

About two weeks ago when I was parking the van up after driving 30 odd miles to home, the engine started to misbehave and sounded like it was running on three cylinders. I shut the engine off and restarted it the next day, after I had surfed the net looking for possible causes. On starting I revved the engine gently and the problem dissapeared. This problem has not reoccured, but it started me thinking, was the loss of oil related to this possible misfire? i.e was oil getting into the cylinder and shorting a plug out. I have performed a compression check (cold engine) and all cylinders are within 12.8 - 12.9 barg, the plugs were all a dry light reddish brown and showed no signs of oil contamination. Just recently I have noticed that the low oil pressure light is occasionally flickering on and then going out, this always happens when the engine is warm and when the engine is either at idle or when i'm changing gear. This latest development is very intermittent and I cannot get it to repeat, it just happens occasionally. The last time it happened I was at idle and was about to switch the engine off, with the low oil light flashing I slowly revved the engine up, supprisingly the low oil pressure light remained on, I then blipped the throttle quickly and the light went out. I turned the engine off and restarted, the oil light came on again but then went out. I checked the oil level when the engine cooled and I was a just below the hi level (F) hole.

Has anyone else experienced anything like this? i.e oil loss but no visble leaks and clean exhaust gases and the low oil pressure light.

The engine was supplied by Grade A Subaru and was sold as a 1999 low mileage engine with less than 60000 miles. I have contacted Grade A and have been advised to do the obvious which is to check the oil pressure to confirm that the oil pressure switch is not faulty.

This is such a shame as I was really begining to appreciate the subaru lump, better economy, better power, better everything apart from all of the above...... I starting to feel quite sick as I have spent in excess of £4000:00 and it's looking increasingly like I have a duffer..

[Pepperami]

Do you have a light oil deposit on the tailgate/rear of the van?

[HarryMann]

As Peppers above, tailgate, it's got to be going somewhere !

I have contacted Grade A and have been advised to do the obvious which is to check the oil pressure to confirm that the oil pressure switch is not faulty.

Thats' the pressure problem, but won't affect the oil usage issue..

Have you checked the bellhousing/engine join for any sign of oil?

If you still think its burning it and not leaking then you could drop the exhaust down and look at each of the ports...

Has it ever appeared to overheat?

What sort of modified sump do you have?

Is it an RJES style conv or an adpater plate jobbie?

[HarryMann]

Another thought...

If you let the oil maintain a level slightly below max for a while, does it then stabilise oil usage or keep going down.. that'll be the crux of the matter.

[silverbullet]

Just how much oil are you losing?
Like everyone else has said, it's either filling the bellhousing, burning it off or leaving it on the road.
I've only once used Grade A for an early alternator. Arrived with a strip of bubblewrap round it and rattling around in a box big enough for a microwave. Surprise surprise it had a lump broken out of the casing.
I grumbled and they went all "Terms and Conditions" on me. They wouldn't accept it back because it had been signed for as OK...
Who in the real world reads all the labels and then opens a parcel on the doorstep before signing? No-one.
Bas###ds.

PS the ticking on cold startup would be the hydraulic tappets in the rocker tips.

[Pepperami]

The most common reason for loss of oil with these engines is the rocker cover gaskets.

[Pepperami]

Another point worth mentioning is (as said before what sump do you have?) If it is a small car one mine was terribly warped because of the welding and I could only stop it P-peeing oil was by using flange sealant. I said flange

[HarryMann]

stubbie

Don't leave it too long before responding about your sump type etc.

[Pepperami]

[stubbie]

Thanks for the replies guys, haven't replied as have been away for a week.
I checked the oil pressure today and when cold the tickover pressure is 3 barg and when fully upto temperature this drops to 1.9 barg, at half throttle the pressure when cold rises to 5.5 barg and this drops to 4.5 barg when fully warmed up. These pressures are well above the 1 barg and 3 barg quoted in the factory repair manual. I have cleaned the pressure switch terminal and will monitor over the next few weeks and let you know my findings. There is no oil escaping from the standard fitted subaru sump, (still waiting for the RJES sump) there is no evidence of oil escaping from the exhausts, there is no oil on the tail gate or anywhere else. I'm will be now checking the oil level in exactly the same place every 50 miles, just in case the drive way is less than perfectly level. The only slight (unrelated) oil leak I have found is from the rear RH side drive shaft, i'm going to fix this next week.
I'm struggling a bit alround as the engine sounds great and pulls like train, the cylinder compressions are all within 0.1 barg and at 12.8 barg are not far off what you would get from a new engine, as for the oil pressure, I'm wondering if the oil pump is occasionaly failing, I also haven't ruled out a bad electrical connection in the sensor circuit.

[stubbie]

The engine conversion uses all RJES bits, there is no evidence of oil leaking from the bell housing.

[Pepperami]

It all sounds good. I would check electrical sensors.

[stubbie]

it's either filling the bellhousing, burning it off or leaving it on the road.
I've only once used Grade A for an early alternator. Arrived with a strip of bubblewrap round it and rattling around in a box big enough for a microwave. Surprise surprise it had a lump broken out of the casing.
I grumbled and they went all "Terms and Conditions" on me. They wouldn't accept it back because it had been signed for as OK...
Who in the real world reads all the labels and then opens a parcel on the doorstep before signing? No-one.
Bas###ds.

Missed this post, how would I check whether the bell housing is filling with oil?

[Pepperami]

Nip up the bolts.

[HarryMann]

If its not a fully sealed syncro one, then it'll drop out..

PS. I had the impression earlier, that you are not really burning or perhaps even losing oil.... hence nmy suggestion that you check what dipstick mark you are using and make sure it is correct and not overfilling.

The question I put to you was this:

If you don't top it up, are you sure it keeps going down ?

Try it (but be careful of course!)

Theory is that it's being grossly overfilled?