G'day guys,

I'm a new member to this forum having just purchased a 1979 1275 Moke. She's a ripper but has a problem that of course didn't rear its head in the test drive.

The car will chug around happily all day at normal suburban speeds where there are constantly changing road speeds, but after sitting on 70 km/h or more for a good 10-15 mintues, she fills the rocker area full with oil which then proceeds to push its way past the oil cap and all over the engine.

The engine runs super-smooth and starts as soon as you turn the key. I haven't conducted a compression test yet, but with the way it runs and the perfect colour of the spark plugs, I'm assumin there are no problems there. No smoke out of the exhaust either.

I was thinking it could be too much oil pressure, the car has an oil pressure gauge fitted and reads 75 psi at cold idle, then about 50 when hot and 75 while cruising. These all appear to be workshop manual specs.

I have pulled the rocker cover off and checked the pushrod holes, all seem to be clear. I have also checked all the PCV hoses for blockages, all seems good there as well.

Would anyone here be able to help me with any ideas with what could be going wrong?

Thanks in advance.

Nick.

the cam bearing at the front of the motor has been fitted upside down

engine out & apart job, though I've heard of people 'fixing' it by putting a piece of feeler gauge with a very small hole in it under the rocker post

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did I tell you that I won a trophy?

Is this a common problem Simon? And is there anyway I can be sure it is infact the problem before I pull everything apart?

Thanks,

Nick.

wait for further replies from people with more experience, but I've heard a few times over the years of the same symptom, with no other apparent problems, and the same cause.

I can see how it'd be easy to do by a machine shop who weren't paying attention or didn't know minis...

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did I tell you that I won a trophy?

Ok, will do. Thanks for your help!

Nick.

Can you please clean out your breathers, you should have one on your clutch cover and possible one on the tappet cover chest which is under the manifolds facing the radiator.
Oil pressure does sound good allround thou

sorry I'm having trouble with photobucket at the moment and cant show a pic of the breathers

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Stop Licking the Dog...I Don't Care Who Started It

All the breather hoses are clear and if you are referring to the oil seperators, I was able to blow back through them with the breather hoses connected without any trouble so I'm sure they are clear.

I agree with Simon, the front cam bush is put in wrong.
When put in right, it lets a short pulse of oil go to the rockers every cam revolution.
If wrong, they get full pressure feed all the time.

Cam has to come out first, hard to do in a 1275 with no tappet side plates on the block.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Ok Dr mini. This cam bearing problem definetly wouldn't show itself at other engine rpm, e.g. idling for long periods or just lower rpm operation? I'm a fairly competent DIYer, do you think I should takle this myslef or should it be left to a shop?

This is interesting, im getting Veras donk back nxt week with the cam bearings put in by my engine bloke, do you have to be a mini fanatic to know wich way to put it in and how can you tell if its in right

Justmoking, there is another way around this problem & its fairly simple, you can make a decent sized (30mm-ish is good) return pipe from the rocker cover (welded in quite low near the gasket line) & hose it down to another 30mm-ish pipe fitted onto the mech fuel pump hole (You`d need to obviously run an electric fuel pump tho)

this is simple & easy to make & you can also add a "T-Piece" into that hose to act as an extra breather

I`ve done this many times & it`s all good, & saves ripping the engine out & apart

Edit--> not the best pics in the world but you should be able to see the big pipe & hose from the rocker cover in these 2 pics

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Thanks miniman. When you say you've done that heaps of times, is that because the motors you've worked with have had their cam bearings in the wrong way or for other reasons? The pics were great too, thankyou.

I think I'd rather pull it out and fix it because I would always have that nagging thing going on that something really isn't right.

Nick.

A common problem due to the cam bearing being fitted the wrong way around.

I have fixed this problem a few times over the years by removing the rocker gear & fitting a brass restrictor into the rocker post oil feed hole. You can use the end of a SU needle to block the hole & use a small number drill bit to drill a smaller hole into the brass.

But really, the best way is to pull the engine out and fix the bearing.

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Have a Nice Day.
If already having a nice day please disregard.

Nick, sometimes even with the cam bearing fitted correctly, the front cam bearing may be a bit worn, the cam itself a little undersized etc,,, any of these things can cause constant oil supply instead of impuse feed, so yes i`ve had to do the big drain pipe to quite a few mini donks,,, heaps of people in the past have fitted a restrictor in the rocker poillar ot the head or into the oil passage in the block to "Try" to achieve a similar result, but i much prefer the big oil drain/breather idea, but that`s just me

& BTW,,, the 2nd pic may be a little miss-leading,,, the hose to the windscreen washer bottle is not the one i`m talking about,,, it`s the one underneath that one that i mean... you can also see both those pipes on the rocker cover in the first pic

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Thanks 850man. Sounds like a good idea. So does yours miniman. Yes, I can see the pipe you are talking about and how it goes down to the fuel pump. I see your point about how many things in the cam area could cause it. It isn't by any means a daily driver so it would be nice just to see if the bearing was in the right way. Would a new one be hard to come by if it is worn?