Oil pump, weak pressure relief valve ??

[Mrs hoskins]

Engine runs well, smooth and quiet, uses no oil either burning or dropping, doesn't overheat.

Few simple questions , before I start on course of action.

Oil pump, Where the hell is it ?
Is it as easy as .....undo 4 bolts and remove ? The Haynes manual is very clear , but looks as if you just remove four bolts?
The difference in price between new one and a rebuild kit is about 30 quid, so is buying a new one the best way ?

My oil pressure is low, and despite reassurances , I want to do a few simple things to see if I can improve it , before I start to get into the more complicated and expensive things.

The oil pressure is only 25 when hot, but never drops below 15 at 800 rpm tickover, suggesting a weak pressure relief spring?

So my initial approach is .......new oil filter, refill with Valvoline VR1 ,with some Lucas additive, and fit a new oil pump.....less than 100 quid all in.....and see if that improves oil pressure

Dave

[jleyton]

Stag paranoia got to you Dave ?

My pressure is similar to yours, as I've mentioned before, and I'm certainly not going to be doing anything about it in a hurry. However, if you're determined to do something then filter and change to VR1 are the first things to do.

Oil pump is pretty easy to do although as it's just above the front right hand exhaust down pipe, you'll probably have to drop that - not so easy . I certainly wouldn't fit a new pump, especially if you've got an original Hoburn Eaton one. Check all the vitals in yours, as per the ROM, and consider using a rebuild kit from LDparts. New pumps will, almost definitely, be Indian built County ones with incorrect spring.

Besides, low pressure won't be a relief valve spring problem.

Cheers

Julian

[Hughesy]

David & Julian, My experience when I changed over to a David Firth type of relief spring was an increase in idle oil pressure. I put this down to the David Firth style of spring has many more coils compared to the original/County and hence a lower helix angle which enables more uniform seating of the relief valve and smoother operation. Craig

[flying farmer]

Idle pressure is not affected by the relief spring as there is not enough flow to open it.

Generally, if the oil pressure rises very quickly with increasing revs then stays steady when the revs increase further (perhaps over 2500rpm), then the maximum pressure achieved is dependant on the strength of the spring.
If the pressure continues to rise at ever higher revs it usually signifies that the crank or pump or jackshaft bearings are worn.

As Julian says, first thing to do is a change to VR1 and a new filter and see what happens then.
Neil

[DJT]

David & Julian, My experience when I changed over to a David Firth type of relief spring was an increase in idle oil pressure. I put this down to the David Firth style of spring has many more coils compared to the original/County and hence a lower helix angle which enables more uniform seating of the relief valve and smoother operation. Craig

Must get around to fitting mine sometime............

[Mrs hoskins]

Thanks chaps....no one told me this level of paranoia came as part of the package.��. Do the Samaritans do a special help line for owners ?
The problem is a mixture of reading to much on the forum, and then a dose of "Stagocondria" ....imagining that everything I read , is wrong ��
I need to relax into the " just squirt it with WB40 and all will be well" frame of mind.
Thanks again
Dave

[DJT]

Thanks chaps....no one told me this level of paranoia came as part of the package.��. Do the Samaritans do a special help line for owners ?
The problem is a mixture of reading to much on the forum, and then a dose of "Stagocondria" ....imagining that everything I read , is wrong ��
I need to relax into the " just squirt it with WB40 and all will be well" frame of mind.
Thanks again
Dave

Dave,

Just follow this advice:

If it moves, but shouldn't, use:

image.jpeg

If it doesn't move, but should, use:

image.jpg

[Hughesy]

Must get around to fitting mine sometime............

Mine increased a few PSI at idle with the new spring. I also compared two new pumps fitted with the same David Firth spring. Original Holburn Eaton & County with the Holburn Eaton giving higher idle pressure. Craig

[Mrs hoskins]

I'm also assuming that if I drive with respect for the car, ( and I'm not a mad speed freak) and cruise in the style of a Grand Tourer, rather that a Muscle/Sports car, then I'm less likely to break something. If I wanted a thrash mobile, I'd buy a Mustang !
Even on a motirway run , I tend to stay around 3000 rpm max, which just above 60mph , which feels comfortable, and doesn't mess my hair ( I wish)

Thanks for the advice....and much more fun than header tanks !
Dave

[kev100]

I'm also assuming that if I drive with respect for the car, ( and I'm not a mad speed freak) and cruise in the style of a Grand Tourer, rather that a Muscle/Sports car, then I'm less likely to break something. If I wanted a thrash mobile, I'd buy a Mustang !
Even on a motirway run , I tend to stay around 3000 rpm max, which just above 60mph , which feels comfortable, and doesn't mess my hair ( I wish)

Thanks for the advice....and much more fun than header tanks !
Dave

I just posted this in another thread, and occasionally you do have to give it a good thrashing, driving at low revs may seem like a good idea, but an engine is not designed to be driven all the time at low revs

"!I bought a Mk3 escort back in the day, previous owner never went above 40 MPH, thought it would be a great engine because of that, I got in it, gave it some wellie up the motorway, all the sludge that had collected in the sump started to circulate, blocked up the oil pump and ceased the engine .. result, a new engine,

Moral of the story .. whenever you buy a new car .. give the engine an engine flush .. just in case, as a one careful lady driver owner cost me 400 quid 2 days after I bought the car under the assumption that a car that has not been thrashed will not give any problems. (the engine was perfect by the way .. it was the conditions that caused the problem)

The irony of this story is it was the time I was a mechanic in the 80's, and the previous owner was the secretary at the garage I worked at, and had the car serviced regularly by me, including regular oil changes .. go figure .... "

[Mrs hoskins]

Totally agree with the " give it a damn good thrashing every so often, just to let it know who is boss". I applied the same logic to all ten of my wives, never did them any harm.....
But I do agree with the need to run the car.....just not to the extent of my neighbour, who recently completed the total rebuild of his beautiful 1967 Mini Cooper...and then , straight out of the garage , gave it a 120 mile motorway thrash at over 80 mph .......sufficient to say that all the tricks he learned on the first engine rebuild, are being put to good use on the second engine rebuild, I was amazed that a guy with the skill to do a restoration to the level he did, didn't seem to know or understand " running in,please pass"

[davidf]

To Julian and Neil
Actually, the relief valve can open at tickover. It is pressure sensitive, not flow sensitive (yes, they are related, the pump creates flow, the resistance of the oil to pass through the bearings creates pressure). The original spring allows the valve to open at very low pressure, which in a good engine is easily achieved at tickover. A simple test is to insert a small spacer under the split pin which holds the relief valve.

[Mrs hoskins]

So, I haven't tackled the oil pump yet, but changed the filter, and oil today ...... Valvoline VR 1 , plus some Lucas additive from the States.....amazing , instantly an extra 10lbs pressure. Obviously whatever underlying problem regards low pressure are still there, but after 40 years of oil changes , I've never known an oil make that much difference .

One question, Ive managed to over fill by a pint...do I need to empty a pint ? Or is it ok ? Overfill has never been a prob in the old camper, that's desperate for any oil I give it !

[stag8manod]

A pint is a fair bit. What you don't want is the crank and rods dipping into the oil and causing it to aerate and foam with a resulting loss of oil pressure. Therefore I think it would best be removed.
Cheers, Ian A.

[Mrs hoskins]

Thanks Ian , just off to garage with spanner , mrs not happy , but I said its life n death....... I'm locked out now