another oil pressure problem

[Dean]

hello, i hope someone can help

i have just built up my engine, and yesterday filled it with oil, back filled the pump, fitted a gauge and powered up the starter, and with in 10 seconds the gauge hit 100psi, left it over night and

1. today i replaced the cooper s relief spring with a a standard spring and got NO pressure.
2. changed it back and it hit 100psi
3. i know its too high so i cut off 1 ring of the cooper s spring, no pressure
4. also swapped gauges in between both times, both are working gauges , no pressure
5. i have a spare uncut cooper s spring, fitted that, NO pressure.
6. removed the spring and ball, everything was clear and no blocks
7. removed the magnet/filter from the top of the oil pick up, its clean, and oil there.
8. blow out and clean the braided gauge pipe, oil was clean and fine, check gauge with air line,working fine.
9. retested NO pressure
10. back filled pump again, still NO pressure
11. removed pipe from block to filter housing, it seemed dry???????? but i had pressure before??????
12. back filled pump again and turned engine backwards by hand and oil and sucked down turned forward and it cam back up,
also came backwards out the filter housing??????
13. re filled everything, back filled the gauge pipe, made sure everything was tight. still no pressure.

i have 2 things i can think of, the turbo pumps not sucking up oil
blocked filter or housing

engine spec and what i have done.

1071, complete engine and gearbox rebuild
new turbo pump
MS central oil pickup,
magnet/filter at the top of the pick up pipe
sealing ring was fitted when engine and gearbox was bolted together
braided hose to filter housing.
new unipart screw on filter, filter pre filled before fitting
Castrol R oil. used to build the engine and not been mixed with anything else.
cooper s spring and ball bearing.
tapped gallery plugs ( m14x 1.5)
braided oil gauge pipe, working smiths oil gauge,

before cranking for the first time

filled the engine with 7.5 pints ( 4.83L) of oil
pre filled the filter
back filled the pump, and rotated engine backwards
checked connections were tight and not leaking,
dipstick hole plugged as i don't have one yet

connected a battery to the starter and with in 10 seconds or so i bit 100psi, first time

i know its and long list but i am not really puzzled wahy i don't have any pressure????
dean

[Spider]

OK two thing hit me in the eye;-

1 -The Turbo Oil Pump. These have WAY too much pumping capacitity for a non-boosted application or anything else that doesn't require the extra litres/minute that these pumps supply. Because it's pumping more oil, the releif valve dump port is way to small to dispose of that additional oil, so it shows up as extra PSI.

2 - Now no doubt this may be riducled. The Ball Bearing used in place of the original bucket. I've seen these ruin far more engines than I care to count. The first bit to this is that you need to shorten the spring a tad if you're hell bent on using one, as it makes the spring sit 'tall' when fitted. Fit up a stock bucket, with the sping, then offer up the screw in cap, but don't screw it in. Measure the gap between the face of the cap and the block, then do the same with the ball bearing. What ever the difference is, that's what needs to be cut off the spring.

Now, I really don't like these Ball Bearing Relief Valves in the slightest. The ball is the wrong shape for the seat and so the valve will not operate as it is intended. Further, they are too loose a fit in the relief valve bore with next to no side length, so as it starts to lift off the seat, a good deal of the oil pressure that's lifting will also get behind the ball thrus trying to close it. Net result being, it won't regulate the pressure, particularly with cold oil, as it should. I've also seen two of these where that have chattered on the seat as a result of this occuring and doing some damage to it. Another problem with them is the spring won't ever sit dead on the back of the ball, it will always go to one side of it, thus side loading it as well, further exacerbating the problem of oil going around behind the ball.

Have a good look around at nearly all hydraulic valves and in particular relief valves, I have yet to see any that have a ball shaped needle, they are all tapered.

[Dean]

thanks for your response

the only reason for the turbo pump, was MS had taken all there standard pump off the shelf at the time due to a complaint of tolerance problems,
so it was the next bed thing, i did not want any old pump and trust MS, unlike other suppliers, but i also knew the turbo pump would pump too much but was also told that it would not be a problem as such,

since looking into the relief spring and ball, i have read many people complying about the ball, so i think i order up an original plunger and spring,

but it still does not explain way the pump does not seem to be sucking up oil, when its new , or why i had pressure, not nothing.

so it looking like i have to change the pump, not so bad to do but just a pain in the arse when i just got it all together

[graham in aus]

Sounds like you had an excess of oil / pressure, now very little / none.....

What type of drive to the oil pump from the cam? Pin / spider?

I would have thought the Turbo pump would be the later slot type?

Has the excess pressure blown out the gasket behind the pump? did you check the pump bolts weren't bottoming before nipping the pump?

Sadly if you can no longer get any pressure, I think it's got to come out

[LarryLebel]

You don't need to cut the spring ... just put washers or shims under the head of the plug. If you need more spring pressure put a washer under the end of the spring.

[rich@minispares.com]

my er-cooper had nothing but trouble with a ball fitted (in that I had over 100, cut the spring and had wild needle swings, cut it a bit more and had nothing), I think the seat was the wrong shape for it, I refitted a std shuttle and normal service resumed

[Dean]

LarryLebel, why did i not think of that, it makes sense, as once you cut it , you can't stick it back on but you can remove a washer

yes the turbo pump is a slot drive 2 bolt pump , and no the bolts were not bottoming in out,

at the minute the engine is sitting on a trolley so changes are easy.

quick up date,i have listened you all your comments, so i have removed the ball and spring and replace it with a plunger and standard spring. and also polished the plunger to help to eliminate it sticking

before i tested for oil pressure, i check to see if the pump was suching and pumping, i removed the braided pipe from the filter housing, put it in a pot then crank the engine to see if the pump was pumping, not a drop came through , so the pump was not doing its job.

so off come the starter,flywheel , drained the oil,and unbolted and removed transfer housing, to replace and check the oil pump.
now to think of it the gasket around the outlet was very oily so it may of blown the gasket so it was pumping underneath, yes the gaskets was properly fitted.

i some how had a brand new spare oil pump,( wish i found it before) new gasket and bolted it back on, cleaned up the casings and got the transfer casing back on,
tomorrow i finish the rest off and check for oil pressure again, fingers crossed

[Dean]

ok its all back together with a standard pump, spring and plunger.
and have oil pressure again, what a relief, and about 70psi.
is that a bit high for just cranking. should get it down a bit but adding another copper washer to the cap. maybe below 60psi





dean

[Spider]

Cold oil, new engine, yeap, I'd be quite happy with that.

[Dean]

well, thats good

thanks for everyones help. next is to get it running