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no oil pressure with starter motor only
bikecarbfred - 31/12/18 at 02:46 PM

just finished rebuild of a 16v afh polo engine carb setup.

thought id send some oil around the block with starter motor only.

but the after market oil pressure gauge did not budge.

did 3 seconds then stop

another 3 seconds then stop

then 5 seconds and then stop


the oil pump is brand new. the oil level is correct. the oil pump simply fits onto crank end and as crank spins, it spins.

the oil filter was pre-filled with oil but apart from that all the galleries would be bare dry hence wanting to do a slow prime with starter motor.

worth just putting plugs in , fuel up and give it a start?


p.s the oil pressure gauge is located at the very top far side of the engine with a 1.5 metre tubing to the gauge it self.


RichN - 31/12/18 at 04:24 PM

Could you connect up the standard oil pressure switch that operates the light on the dash? See if that goes out, could be a faulty gauge?


bikecarbfred - 31/12/18 at 04:55 PM

i've got the vw one plugged in too, but they only work when engines running. dont think it operates with starter motor only.

the after market one works because i got an air gun and blew air into it and saw it move.

i made sure i didnt blast air at close range to avoid damage.


ken555 - 31/12/18 at 04:58 PM

Stupid questions I know, but are the spark plugs out ?

the starter might need the extra speed with having no compression to fight against


Regan_M - 31/12/18 at 05:05 PM

Was the new oil pump primed also? with my zetec rebuild I had the same issue and in the end I removed the oil pressure sender and forced oil in the galleries and also removed the oil filter and using a 500ml syringe forced oil directly into the oil pump.

It then generated oil pressure upon cranking the engine


rusty nuts - 31/12/18 at 05:24 PM

I’ve had problems with oil pressure on VWs a couple of times, the last was on fitting a reconditioned engine , I suspect the oil pump hadn’t been primed. I ended up removing the oil filter then cranking over until oil came out then filled the filter before refitting . It maybe possible to pump oil into the oil gallery after removing the pressure switch . Always prime oil pumps with Vaseline before fitting especially if it’s going to be some time before the engine is run.


bikecarbfred - 31/12/18 at 05:57 PM

yea spark plugs out.

i would say it's between 200 rpm & 300 rpm




oil pump wasnt primed. oil filter was not full to top. it was 3.4's full.

galleries were not fed with oil as the whole idea was a few seconds of starter motor action to get it around somewhat.


just took oil gauge off and its born dry, theres no oil going to top of head.


slipped up. shoudl have thought of this earlier.!!!

take oil filter off and see if oil splashes out. oil filter is half way down on engine so that's near to pump.

[Edited on 31/12/18 by bikecarbfred]


Regan_M - 1/1/19 at 07:22 AM

Prime the oil galleries and oil pump as best you can as this will certainly help


02GF74 - 1/1/19 at 02:10 PM

Pack the space between the lobes with vaseline . It won't flow out and dissolves in oil, so don't use any other grease. It's standard practice on rover v8.

[Edited on 1/1/19 by 02GF74]


bikecarbfred - 1/1/19 at 02:57 PM

took oil filter out, was dry around the housing, should be wet with oil.

shoved a pipe down gallery towards oil pump, hand oil pumped oil down that gallery until it spewed back out around the pipe.

cranked engine on starter and oil poured out from oil filter hole. did it three times.


am i good to go? how long before oil pump dries out ?


BaileyPerformance - 1/1/19 at 03:28 PM

with hindsight always a good idea to pack pump with vasoline.

to prime, put oil into oil gallery via oil filter housing, turn engine backwards, fill filter with oil and try to fit without getting it everywhere.

remove plugs, keep cranking until you get oil light out, dont stop, may take 30 seconds or more


BaileyPerformance - 1/1/19 at 03:29 PM

on i side note, if engine new MUST use running in oil, or second best CLASSIC 20W50


bikecarbfred - 1/1/19 at 06:51 PM

@ bailey using joe gibbs break in oil.

ive got everything fitted, to see oil come out of the oil filter hole was good enough as along as it was not the oil i pumped manually into the galleries towards the oil pump. the gallery was around 8-10 inches long, a straight path up to the oil pump. diameter if gallery around 9-10mm


im going to give it a start and hope the new oil pump is actually sucking from the pan.

4 seconds enough? then see no reading cut the engine off?

p.s oil filter is full about 3/4's


Bluemoon - 1/1/19 at 08:16 PM

I would not run it up until you can get some oil pressure on the starter. My cvh will take 30 seconds if stood for a few months. i.e 30 seconds on starter with ignition off to get oil light of..


bikecarbfred - 1/1/19 at 08:19 PM

30 seconds on a starter. the rings will be running dry for 30 seconds

i thought high rpm start would be better?

suppose will have to take spark plugs off, carbs off, to do the starter motor way.

shall i pour some engine oil through spark plug hole on top of cylinders

[Edited on 1/1/19 by bikecarbfred]

[Edited on 1/1/19 by bikecarbfred]


bikecarbfred - 1/1/19 at 09:46 PM

is there a possibility that the oil i fed through the gallery from oil filter hole to the oil pump was the only oil that was squirting out from the oil filter hole when cranking ?

is this scientifically possible or must there have been oil dragged from the pan up the pickup pipe into pump that forced the oil i fed through, back out?


that's all i need to know now


steve m - 1/1/19 at 10:12 PM

Xflows, can take a bit of time, to get pressure up, even mine does if not started for a while

Don't forget that if your running a capillary gauge as I am, it needs to crank over quite a while to build pressure , and run it up the 48" of pipe to the gauge,

Why not take the pipe off the gauge, and pop the pipe into a jam jar, and crank it over for 15 seconds, I bet your get oil in the jar then!

If not, your pump is knackered

steve


bikecarbfred - 1/1/19 at 10:25 PM

pumps brand new.

sorry to repeat the question but would be brill if someone new the answer to the below.


is there a possibility that the oil i fed through the gallery from oil filter hole to the oil pump was the only oil that was squirting out from the oil filter hole when cranking ?

is this scientifically possible or must there have been oil dragged from the pan up the pickup pipe into pump that forced the oil i fed through, back out?


BaileyPerformance - 2/1/19 at 01:04 PM

quote:
Originally posted by bikecarbfred
30 seconds on a starter. the rings will be running dry for 30 seconds

i thought high rpm start would be better?

suppose will have to take spark plugs off, carbs off, to do the starter motor way.

shall i pour some engine oil through spark plug hole on top of cylinders

[Edited on 1/1/19 by bikecarbfred]

[Edited on 1/1/19 by bikecarbfred]



All you have to do is put a drop of oil down the bores. You will not damage the rings if you cranked it for a hour.


bikecarbfred - 2/1/19 at 01:41 PM

why won't rings damage if cranking for an hour without oil.

say starter motor is turning the crank at 200rpm.

is that too slow for rings to get damaged?

if that is the case then ill be doing starter motor way for sure.

[Edited on 2/1/19 by bikecarbfred]


AdamR20 - 2/1/19 at 02:00 PM

As said, drop of oil in the bores, job done.

I've cranked freshly built engines for 20+ seconds on the starter before to get pressure, no ill effects as long as plugs are out and everything lubed correctly when installed.

[Edited on 2/1/19 by AdamR20]


02GF74 - 2/1/19 at 06:55 PM

I'm not familiar with your engine but hopefully the questions still apply.

1. You rebuilt the engine, did it have oil pressure beforehand?
2. Where the same parts used i. e. The same sump and pick up tube.
3. Was it assembled correctly, i. e. Is there a f
Gasket for the pick up tube and oil pump and if so, are they fitted in correct orientation so ad no to block off oilways. The pick u tube needs to be air tight in order to suck up oil.
4. Is pick up tube / gauze clear.
5. Is oil pump pressure relief valve free.
6. Is there the correct amount of oil in the sump, typically about 4-5 litres, rules out having the wrong dipstick
7. Is the correct oil filter fitted and primed
8. Are there non stock parts such as oil cooler, thermostat fitted and fitted correctly.
9. is there an oil pressure switch fitted, removing this should result in oil squirming out of the block.

Once primed as stated above, oil should be visible at the cylinder head after 30 seconds or less of cranking the engine over, it certainly does need an hour!!!

How far in the chain: pick up tube, pump, cylinder head oil ways does the oil get to.


steve m - 2/1/19 at 07:55 PM

Hicost, back in about 2000/2001 drove his car 15 miles to my house and 15miles home with NO oil pressure at all, because of an oil pump issue

However the following day, having put a new oil pump in, drove it to Castle donnington
His engine was a cosworth, and ran for several more years

Assuming the engine was built properly, and with assembly lube, cranking an old crossflow for 30 seconds, is not going to kill it

Ive cranked mine for minutes, to get pressure up after a rebuild, and mine has a high torque starter, got to be 300 plus revs
not the weedy standard starter of under 100 rpm

steve


bikecarbfred - 2/1/19 at 08:44 PM

yea it's abit stressful this engine building lol.

anyway i did what ya said , dropped some oil down spark plug hole. think i over did it, about a tea spoon in each one. could even see reflection of my eye in it .

cranked it on starter motor , took around 5 seconds and got oil pressure, 2 bar, then 3 bar, 4, then 5 bar then turned it off.

seemed like it was going to go over that aswell. the gauge only goes to 8 bar.


02GF74 - 2/1/19 at 09:18 PM

You checked oil is getting to top of engine, namely the camshaft?

Is it after market oil pressure gauge.?
At what pressure is the relief valve meant to open?. From memory, depending on the engine, normal pressure can be anything from 30 to 60 psi

[Edited on 4/1/19 by 02GF74]


bikecarbfred - 2/1/19 at 09:41 PM

definite getting to top of engine as that's where the mechanical gauge is.

don't know when relief valve opens at. its a new pump but yeah 5 bar is when i turned it off, maybe when the engines running that sort of pressure will open the valve, and when oil warm up it should settle down to 3 bar (45 psi) at 2000rpm


ken555 - 2/1/19 at 09:43 PM

Is it a new oil pump, because isn't the relief valve built into to it ?

The specified figure for the afh/aee oil pump is 300kpa at 3000rpm (or in laymans terms 43.5spi when you rev it)
but this is with warm oil (80c)

Cold oil I would expect more, but not at the low revs off the starter.


bikecarbfred - 2/1/19 at 10:06 PM

yeah, its a brand new pump.

i didn't allow it to settle down. i just thought, cool, im getting pressure, 2 bar, then 3, 4, 5 in quick time, then switch it off. maybe it needed another second or so to burst open the valve,

yeah i believe the valve is built in the pump it self. a little ball bearing with a spring


BaileyPerformance - 3/1/19 at 03:02 PM

quote:
Originally posted by bikecarbfred
why won't rings damage if cranking for an hour without oil.

say starter motor is turning the crank at 200rpm.

is that too slow for rings to get damaged?

if that is the case then ill be doing starter motor way for sure.

[Edited on 2/1/19 by bikecarbfred]


The rings of an engine are not under much pressure with the plugs out, even with plugs in unless the engine fires the loan is minimal. Ifworried (and it speeds up cranking) put a drop of oil down the bores

Cheers, Dale


bikecarbfred - 3/1/19 at 04:49 PM

quote:
Originally posted by BaileyPerformance
quote:
Originally posted by bikecarbfred
why won't rings damage if cranking for an hour without oil.

say starter motor is turning the crank at 200rpm.

is that too slow for rings to get damaged?

if that is the case then ill be doing starter motor way for sure.

[Edited on 2/1/19 by bikecarbfred]


The rings of an engine are not under much pressure with the plugs out, even with plugs in unless the engine fires the loan is minimal. Ifworried (and it speeds up cranking) put a drop of oil down the bores

Cheers, Dale


I did what you and other lads said and it worked. got oil pressure. so from no oil pressure i now might have high oil pressure lol

Is it ecpected to have high pressure such as 5-6 bar with a new build on starter motor

[Edited on 3/1/19 by bikecarbfred]


BaileyPerformance - 3/1/19 at 05:30 PM

Thats about 80psi, does seem high.
Have you got remote oil filter or oil cooler? if so remove and fit filter back on the engine


bikecarbfred - 3/1/19 at 08:07 PM

just a normal cylinder shape filter which screws on front of block

i didnt allow anything to settle. soon as i saw pressure going up and up and up i turned it off.

don't want no galleys plugs to blow out of engine


02GF74 - 4/1/19 at 06:50 PM

quote:
Originally posted by bikecarbfred

don't want no galleys plugs to blow out of engine


Of course not, better have that happen on the road so unsuspecting motorcyclists can have a good skid.

Seriously, this needs looking at, if indeed there is a problem. I updated pressure range in previous post a D it does seem to be high.

Regardless of engine temperature, the oil pressure relief valve limits how high pressure can go.

With a worn engine, oil pressure will drop when warm as it is not high enough for the valve to open.

Question is: do you trust the pressure gauge?


bikecarbfred - 4/1/19 at 10:48 PM

quote:
Originally posted by 02GF74
quote:
Originally posted by bikecarbfred

don't want no galleys plugs to blow out of engine


Of course not, better have that happen on the road so unsuspecting motorcyclists can have a good skid.

Seriously, this needs looking at, if indeed there is a problem. I updated pressure range in previous post a D it does seem to be high.

Regardless of engine temperature, the oil pressure relief valve limits how high pressure can go.

With a worn engine, oil pressure will drop when warm as it is not high enough for the valve to open.

Question is: do you trust the pressure gauge?


i dont mess with motorcyclists lol,

do i trust the pressure gauge. I trust it to be no worse than 1 bar off the true reading either way.

it's not relief valve as pump is brand new.


rusty nuts - 5/1/19 at 08:30 AM

quote:
Originally posted by bikecarbfred


it's not relief valve as pump is brand new.


If you think because it’s new it’s not faulty then I think you should wake up


bikecarbfred - 14/1/19 at 05:43 AM

well i got it running up to 2000rpm then switched it off after 3 seconds.

noticed there was fumes in the garage almost instantly on starting, greyish, dark. stunk of oil.

i was more concerned with the noise. there was no mechanical knocks or screeches.

just felt like a loud engine and very deep sound. i think the loudness was the garage.

but felt deep.


if the vr sensor on megajolt is not telling the right firing points this can affect timing.

on the megajolt software if the rpm matches whats on the car dashboard rpm dial then this means the vr sensor is accurate?