Oil Housing Differences etc.?

[Chief]

Hi,
Somebody asked the same question (with a handy image) on this forum some time ago (both are Purolator, even though the thread doesn't state this - that much research I've managed to do myself):
https://www.morrisminorforum.com/forum/ ... ion.36677/

However one thing I wanted to check was why the one on the right in the photo has a much larger central hole than the one on the left?

Is the one on the right only for a 948, the other to provide more oil to a 1098/1275 or doesn't it matter either way? (I have a 1098).

I notice the gasket that ESM sells would fit perfectly on the right hand one with the larger central hole, however MOSS sells a gasket that is a perfect circle with a small hole like the left hand one, so you can see how this adds to my confusion.

And also, should you oil the block to housing gasket before fitting? and does anyone know what size/length the block housing bolts are as the normal suppliers all seem to be out of stock for them.

As to why I'm asking this, my car currently has a spin on conversion, but I have a whole load of original filters so I'm debating switching back, the conversion was only done to stem the tide of a major oil leak many, many years ago and I'm (slightly) more knowledgable about these things now.

Thanks

[geoberni]

When you say 'this forum' you obviously mean 'this other forum'.....

[philthehill]

The size of the hole in the filter head block face does not effect the flow of oil.
All the filters/filter heads are interchangeable though you may have to adjust the metal pipe from the block to suit.
Both gaskets will suit either filter head but best to use the correct gasket for the filter head.
I would advise that the gasket is lightly greased.
Just been reading about NOS oil filters - apparently the cellulose used in the manufacture of the paper filters breaks down over time and can cause the filter element to disintegrate with disastrous results so I would be wary of using NOS paper filters.
The studs are 3/8" UNC were they screw into the block and 3/8" UNF at their outer end. They have an overall length of 4 1/2" approx.
Only the later filter heads were secured to the block by bolts.

[Chief]

Thanks for the replies

When you say 'this forum' you obviously mean 'this other forum'.....

The curse of editing your post multiple times, originally it read "this forum: (link)"

so I would be wary of using NOS paper filters.

It's because of the amount of service kits I've bought over the years from ESM and BM as a "just in case" and then only used a few parts from them, but I do take your point about the weakening of the cellulose.

I would advise that the gasket is lightly greased.

With normal grease (as in the yellow gunky stuff)? as opposed to say copper or some other grease?

The studs are 3/8" UNC were they screw into the block and 3/8" UNF at their outer end. They have an overall length of 4 1/2" approx.

With nuts on the end to secure the oil housing in place? I presume bolts are an easy option since they appear to just go through the housing (which in pictures doesn't look threaded) and keep everything in place within the block?

[oliver90owner]

A little more research from yourself would be easy enough and may not go amiss. It would have answered your query without posting.

The crank is (clearly?) the major recipient of the oil supply, from the pump, for lubrication purposes.

Work out the areas of leakage for an engine at the service limit of, say of crankshaft bearing wear.

Double(?) that area - for cam and valve gear - and calculate the area of the orifice under discussion, Compare the results you obtain.

A fairly simple task, really.

The issue of the gaskets is simple enough enigma to solve. Loose overlap, if lesser quality gasket material were used, could conceivably come adrift and block an oil-way. Would any good mechanic/engineer take that risk?

[philthehill]

The studs had spring washers and nuts to keep the filter head to the block.
Smear the gasket with Castrol LM or similar grease. No Hylomar or other sticky stuff required.
There are no threads in the filter head casting. The studs/bolts pass straight through the filter head.

[Chief]

Thanks, I'd never actually heard of Hylomar anyway (mind you, it was only probably last year I learned of copper grease)