Top End Lubrication

[horse321]

I have a lack of oil at the top end of my 1098 van engine. The engine was rebuilt approx 5 years ago but has suffered it's second cylinder head gasket failure between cylinders 3 and 4 since this rebuild. On investigation I have noticed a complete lack of oil covering the rocker assembly and rocker cover! In fact this shows signs of rust!

After the first cylinder head failure I was told the oil pressure was good, so I discounted the oil pump at that stage!

The Van is used regularly, in fact is my main transport! But it is mostly short town work.

So my questions are before I strip the engine do the A series experts think the problem mostly likely mean there is a blockage in the oil feed, or should I look at replacing the oil pump? Or any other ideas?

Could the cylinder head failure been the result of the lack of lubrication, or do I have an additional problem?

Any ideas gratefully received

[bmcecosse]

Welcome to the forum! That's quite a story - I amazed it hasn't seized up. Assuming you have oil in the sump up to the right level - does the oil light go out and stay out all the time ? An oil pressure gauge would be a good help here too..... The rockers are fed from a delivery port that comes from the front camshaft bearing and runs up in a small tunnel to the block/head interface. Obviously the gasket must be on right way round so the hole in the gasket lines up with this and the matching port in the head - but in fact - it's not possible to put the modern gasket on in a way that could block the hole although I'm not sure if very old gaskets had holes at both ends...... The oil then travels up through the head to meet the rockers - where it should meet a pillar with a hole up the middle to allow the oil to travel up and into the hollow rocker shaft. It could go wrong here if the rockers are wrongly assembled - and the pillar with the hole is NOT over the hole in the head - also if the rocker shaft has been assembled incorrectly - the port in the shaft that permits the oil into the hollow core could be in the wrong place - or it could simply be that the rocker shaft is hopelessly choked with 'solid' oil residue. So - I'm afraid you will need to strip off the rocker assembly drain the water and loosen ALL the head nuts just slightly - then remove the spark plugs and run the engine up on the starter and see if oil appears at the tunnel port at the front of the head - if it doesn't then there is something seriously wrong inside the engine and it will require to be stripped - but start by taking the head off first and checking again for oil at the port at the front of the block - and the gasket for a matching oil hole........ If oil appears on the head - then the problem lies in the rocker assembly - either fit another known good set - or clean out/re-assemble the set you have so the pillar with the hole is above the hole in the head. It's unlikely the gasket would blow because of this - but IS extremely likely the rocker assembly and the valves and guides in the head will be very badly worn due to the lack of oil..

[horse321]

Thanks for your most comprehensive reply! I will take a look and see how I get on! Thanks again