Land rover 90 2.5 NA diesel problem

Hi, I have a 1987 land rover 90 which is leaking oil from the oil filler cap. I have checked the oil level and its fine. If I stop the oil coming from the cap it starts to come out of the dip stick can any one help

Kevin.

*cue POS*...

Sounds like your piston rings/pistons/head gasket/head/etc is worn/damaged, allowing the crankcase to become excessivly pressurised.

However... Replace the o-ring in the filler cap, they cost 50p from paddocks, and make sure that the mesh in it isn't blocked - some crank case pressure is normal, which is why they have the breather on it, connected to the inlet manifold to provide a mild suction against it.

If the leaking isn't excessive, this will fix it, cos blocking the top up completely will mean that the pressure will build up, and the dipstick is the easiest place for it to come out of next.
Hope this helps.

Oo does it burn much oil?

I love topics like this!

Boydy has pretty much nailed it on the head and with these engines it comes down to a number of different things, all of which you can fix for yourself in a weekend at most, but it's whether or not you think it worthwhile.

Originally my 2.5 N/A was blowing oil out of the dip stick tube and there was a lot of pressure forcing oil out of the filler cap. Generally speaking, if the oil filler cap has a poor seal (as suggested), oil will finds its way out because the rockers throw oil all over the place.

The fact that there is a lot of pressure means that something has gone, and its down to you to diagnose the problem and decide whether to fix it or not. What you don't want to be doing, especially with these engines being so straight forward to work on your self, is pay a garage to do the work for you, because you will end up with a £150 to £200 bill plus parts which you would be much better off with yourself!

Generally speaking, if you place your thumb firmly over the dip stick tube for five seconds with the engine running at operating temperature and the oil filler cap in place, you will find that when you quickly release your thumb, oil is physically spat out of the engine at you, or there is a big hiss. If this is the case, I'll explain how to fix the problem. If there is just a little "pfff" and not much pressure, the problem may not be as big as you think, but under no circumstances trick your self into thinking that there is no pressure if it is evidently there, because any steps that you take to fix the problem will not be worth while.

Any way you look at it, you are going to have to remove the head. It's quite a straight forward task, just make sure that you keep all the bolts and push rods in order in a cardboard cut out.

10 simple step cylinder head removal

1) Drain all the coolant from the engine
2) Drain a litre or so of oil
3) Remove the air intake / exhaust manifold (just unbolts)
4) Remove the rocker cover (three nuts / bolts)
5) Remove the injectors so that you can reach the head bolts (just unbolt and prise out)
6) Remove the rocker shaft assembly (8 bolts, comes off as one assembly)
7) Remove each 8 push rods (they just slide out)
8) Remove the head bolts (keep them in order!)
9) Remove the oil return pipe at the back (driver side of the cylinder head)
10) Gently prise the head up and off!

Now all you need to do is wipe the top of each piston clean and examine the crown very carefully for splits or cracks. If there are any, get back on here and I'll walk you through changing them if you think it's worth your time. The only thing here being that the bores could be worn and should you buy a new piston with rings (£25 ish) and fit it, you'll find the same problem occurs in next to no time because the ring will wear down to the shape of the cylinder and there will be gaps in certain places. You'll also need to change the bearings too (10 second job whilst re-fitting!) but the whole re-build could cost up to £250 in parts, which could go towards a slightly more powerful engine. Again, a 200 tdi or 300 tdi engine will cost you more for the extra bits you need for that too so you're talking £150 in parts to fit a new engine, plus any extra on your insurance and the price to rent an engine hoist etc.

Also examine the bores / cylinders. If there's any scoring, it might just be a broken ring, which would still require removing the piston (only two nuts holding it in from beneath) in order to fix.

Let us know how you get on and which route you would like to take. The problem could of course just be (like Boydy said) that the head gasket has blown, but if you're taking the head off, you'd be stupid not to take a close look at the bores and the pistons just in case its them (which is most probable).

Hope this helps a bit!
-Pos

Thanks for your help I will try the test over the weekend and let you know.

Thanks again

Kevin

boydy1989 said:

*cue POS*...

Sounds like your piston rings/pistons/head gasket/head/etc is worn/damaged, allowing the crankcase to become excessivly pressurised.

However... Replace the o-ring in the filler cap, they cost 50p from paddocks, and make sure that the mesh in it isn't blocked - some crank case pressure is normal, which is why they have the breather on it, connected to the inlet manifold to provide a mild suction against it.

If the leaking isn't excessive, this will fix it, cos blocking the top up completely will mean that the pressure will build up, and the dipstick is the easiest place for it to come out of next.
Hope this helps.

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