Mechanics

WHERES THE OIL GOING?

1994 Rover 2 Series

1994 Rover 2 Series 4 cyl Front Wheel Drive Manual 30000 miles

I have a problem with my rover 220 Gsi, I wonder if you can help. Im in Spain and its hard to get some good advice here. (Engine was only rebuilt 30000 miles ago)

My problem is that my car has been using lots of oil now for some time and is now using a litre for about 240 miles.

The car runs well but I do get a slight piston rattle at low rpm when hot when under load.

Yesterday I did a compression test and my results were very high (dry test) I had 248, 259, 251 and 250psi from cylinders 1 to 4 respectively. Plugs were not wet, no 1 was a bit black but not heavy, 2 looked browny dark grey, 3 and 4 a liitle whiter than I would expect.

I was considering buying a rebuilt head for the car hoping that would solve my problem, my worry is if the oil is burning past the rings then it will just be a waste of time and money.

Any advice that can be offered would be much appreciated.

Thank you

Jon
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2carpros4jon
July 29, 2009.




Hi there,

You need to do a leak down test as well, now you may have a faulty oil control ring, this won't affect the compression but it will allow some excess oil past and this will burn off at a constant but slow rate, putting a new head on the old block may increase the oil consumption, dose it puff smoke on cold start ups?

Mark (mhpautos)
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Mhpautos
Jul 29, 2009.
Thanks Mark for your reply.

I was considering a leakdown test but I assumed that if the compresssion wasn't down, a leakdown test wouldn't show bad oil control rings either, am I correct in assuming that, is there any sure what to find out how the oil is getting burned, and why arent the plugs wet considering the amount being lost

cold starts, as far as I know its not smoky but its hot here, 90 deg f approx, there is a slight amount of smoke when warm if you rev high but its very slight.

Thanks again.

Jon

Tiny
2carpros4jon
Jul 29, 2009.
Hi there.

If it's a blue smoke its oil, if a control ring is faulty you will burn small amounts of oil constantly, the plug wont foul as all the oil is being burnt, there is no real test for a faulty oil control ring, short of a visual inspection.

Mark (mhpautos)

Mhpautos
Jul 29, 2009.
Sorry to keep asking, but could the fault just as likely be down to valve guides or stem seals as much as an oil control ring?
The pistons had new rings fitted about 30 000 miles ago and before it hardly used any oil.

I put a new head gasket on a few months ago to fix the common corner oil leak on these engines and changed the sump that was leaky too thinking this was were my oil was going because it was loosing a similar amount before I did that but it slowly uses more and more.
I did notice that the valve that wasn't fully closed did have some play in it but I didn't expose any others to see if they were the same.

Thanks again.

Have a great week

Jon.

Tiny
2carpros4jon
Jul 29, 2009.
Hi there,

the oil can be by passing the valve stem seals, when this happens you do get a blue plume on a cold engine stat up then the smoke clears, this is due to hot thin oil running past the seal and sitting in the valve this collection burns off with the first stat up and the smoke is quite visible, with running conditions there is not normally enough oil by passing to be that visible, also if the oil rings are a bit suspect, you may bet a puff when you back off the throttle at a higher speed as this is max engine vacuum and oil will by pass then.

Mark (mhpautos)

Mhpautos
Jul 29, 2009.
Thanks for that, sound like a great test.
Will get someone to stand behind when the car is cold.

Thanks once more, you've been very kind and helpful.

Jon.

Tiny
2carpros4jon
Jul 29, 2009.
Hi there,

You welcome, let me know how you get on, good luck.
And thank you fore the vote and message.
Mark (mhpautos)

Mhpautos
Jul 29, 2009.
Hi again.

You asked me to update you so here I am : )

I started the car this morning and I didnt notice any smoke, car started instantly as usual but no smoke that I could notice. So does it look like the worst then? I was really hoping it not to be piston related, that will be too expensive to repair : (
one thing I do remember was that when I removed spark plug number 4, smoke came slowly from the combustion chamber, dont know if thats relevant.

Thanks again

Jon

Tiny
2carpros4jon
Jul 30, 2009.
Hi there,

That smoke would just be some incomplete combustion gasses trapped in that cylinder when the engine shut down, go for a drive with some one behind you check for any smoke on acceleration and over run, (throttle off high road speed) see what that shows.

Mark (mhpautos)

Mhpautos
Jul 30, 2009.
Ok, ill try to find someone to follow me. So you mean accelerate hardish and then fully let go of the accelerator and see when there is smoke and when there is not?
Ill have o find someone willing LOL,

Thanks again, I'll keep you posted.

Ps, what results mean what?

Jon : )

Tiny
2carpros4jon
Jul 30, 2009.

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