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Low oil pressure


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#26 _CHOPPER_

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Posted 27 December 2011 - 07:08 PM

It probably came out three times because that's what happens if you hit Post more than once in a short time frame.

#27 _oldjohnno_

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Posted 27 December 2011 - 07:17 PM

Put a known good pump on it and test it again. If your old pump was working well use that. If it is still down on pressure with the replacement pump I'd pull the engine to check the pickup.

#28 _WYLDLC6_

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Posted 27 December 2011 - 07:24 PM

My old one was a hv pump with filter bypass removed, it worked fine will a hv be ok.
Cheers chris

#29 _oldjohnno_

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Posted 27 December 2011 - 07:51 PM

I prefer std pumps but it'll be good enough for testing purposes. If it's all good with the old HV pump then you might be able to return the faulty pump for replacement/repair or just buy another std pump.
When you say the bypass has been removed I assume you mean it has been plugged. If this is the case you'll have to keep an eye on the pressure and change the filter as soon as the pressure starts to drop a bit. If the bypass has simply been removed then the filter will basically be doing nothing.

#30 _WYLDLC6_

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Posted 27 December 2011 - 07:57 PM

I think thats what its called. Its the little brass round goldy coloured thing, could even be steel lol, about the diameter of a 5 c piece.
The standard pump has it but the hv one doesnt.

#31 _oldjohnno_

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Posted 27 December 2011 - 08:18 PM

Its the little brass round goldy coloured thing...


Yep thats it. Has the hole where it used to live been blocked off or can you see straight through it now?

#32 _WYLDLC6_

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Posted 27 December 2011 - 08:26 PM

Block i think, ill have a look tomorrow when back home
Why is this mod done, what are the pros and cons.
Cheers chris

#33 _oldjohnno_

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Posted 27 December 2011 - 08:51 PM

It's commonly blocked off with newly built race engines, the idea being that if a cam lobe and/or lifter fails during the break-in period there's no possibility of the very hard particles being circulated through the engine and damaging the whole thing. It is a good idea with big cams but you have to keep your eye on the gauge because as the filter begins to block the pressure will drop and you may also have low pressure with thick oil from a cold start.
For a street car I'd prefer to have the bypass working normally (or use a filter with a built in bypass), at least after the cam has been broken in.

Edited by oldjohnno, 27 December 2011 - 08:52 PM.


#34 _WYLDLC6_

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Posted 28 December 2011 - 08:52 PM

ok , changed pump, packed full of vaselene, cranked with no plugs cant get pressure at all.
Can this take a while or should i just put plugs back in and see if it gets pressure then.
Cheers Chris.

#35 S pack

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Posted 28 December 2011 - 09:16 PM

ok , changed pump, packed full of vaselene, cranked with no plugs cant get pressure at all.
Can this take a while or should i just put plugs back in and see if it gets pressure then.
Cheers Chris.


G/day Chris

The Vasolene might have clogged up the filter.
Remove the pump, clean out the vasolene and replace the oil filter. Personally I've never found the need to use Vasolene in a Holden 6 oil pump. I just oil the pump gears at assembly, install the pump and then 3/4 fill the filter with oil and quickly install the filter onto the pump. Crank the engine over without the plugs, as you have done, and wait for the pressure to come up.

Cheers
Dave.

#36 _WYLDLC6_

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Posted 28 December 2011 - 09:18 PM

ok, cranked again with no plugs got pressure. Used a known working oil pump and same thing. 30 psi cold idle down to around 15-17 hot idle.
steadily built up revs to around 4000 rpm and still couldnt get any extra pressure 27-30 psi tops.
Shimmed spring about 1mm and absolutely no increase in pressure at all which is odd i thought.
didnt appear to be any pressure loss under load, any ideas fellas.

Cheers Chris.

#37 S pack

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Posted 28 December 2011 - 09:51 PM

ok, cranked again with no plugs got pressure. Used a known working oil pump and same thing. 30 psi cold idle down to around 15-17 hot idle.
steadily built up revs to around 4000 rpm and still couldnt get any extra pressure 27-30 psi tops.
Shimmed spring about 1mm and absolutely no increase in pressure at all which is odd i thought.
didnt appear to be any pressure loss under load, any ideas fellas.

Cheers Chris.


Hmmm, looks like you'll be pulling the engine out and praying you find a crack or a fault in the pick up pipe or the pipe connecting nut hasn't been tightened properly.

Could also be worth removing the timing cover and check the timing gear oiler and the welch plug in the front end of the main oil gallery.

#38 _Drag lc_

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Posted 28 December 2011 - 09:53 PM

does the oil seem airated on the dipstick after this test youve done?

#39 _WYLDLC6_

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Posted 28 December 2011 - 10:00 PM

spack, yeah it does again. I know the plug and welshplug are there as that was the engine builders first thought too. im thinking i might give it a go with a standard sump and pickup.
Hayden, its a bit hard to check as with a dipstick as with the sump shape the dipstick hits the baffles and pushes near the crank and hits, so i have a shortened one in there.
i could still try the long one though. I'll have to give it a go tomorrow though as 11 o clock and very loud car doesnt seem to impress neighbours lol.
Thanks guys.

#40 _Drag lc_

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Posted 28 December 2011 - 10:13 PM

yeah mate go easy on the neighbours. ok does the oil in the tappet cover area look airrated check that aswell. i would imagine if it was sucking that much air it would be visable in the oil but as ive never had this happen im not really sure it might be the gear oiler poped out ? doubt itil be the gallery plug id be suprised if it was still a welsh plug in there at all with the engine specs u gave us.

have u asked the engine builder what grade of oil it shoud take?

Cheers

#41 _oldjohnno_

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Posted 29 December 2011 - 06:03 AM

It"s almost certainly a problem on the suction side, either an air leak or restriction. It's got nothing to do with gallery plugs or the gear oiler or anything else on the pressure side. Sounds very much like the pickup is too high (you could test with another litre or two of oil added) or too low and close to the sump floor.

#42 _WYLDLC6_

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Posted 29 December 2011 - 07:18 AM

Yep it looks like engine out again. I'll try and get my hands on a standard sump and pickup.
Pain in the arse with webers and hm9cy headers.
Any ideas on removing sump without pulling engine out lol.
Cheers chris.

#43 _Drag lc_

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Posted 29 December 2011 - 08:02 AM

i doubt it will clear the flywheel , converter flexplate. idd just rip the mota out then it will be easier for u to inspect what is going on. did u fit the sump,pick up or the engine builder?.

#44 _WYLDLC6_

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Posted 29 December 2011 - 08:20 AM

Yeah i know, bit sick of doing it though lol. My engine builder refitted it all up. Do u think changing the sump/pickup to standard will be an issue for this type of engine or should i try stick with the hi volume sump.

#45 _Drag lc_

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Posted 29 December 2011 - 08:25 AM

i would think it is better to remove the engine 3hrs or so carfully fit to eng stand then inspect the oil problems i wouldnt be just swapping the sumps and pickup without first working out why this is happening.

i would use the bigger sump if it were me.

Cheers Hayden

#46 _WYLDLC6_

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Posted 29 December 2011 - 08:37 AM

this is the hard bit though. Engine builder and i have been trying to chase this problem for 6 months now. he's tested pickup, pressure tested block, changed crank incase something was going on in there, changed oil pumps. I dont think theres much more we can do. Starting to lose patience with it.
Cheers Chris.

#47 73TORANA!

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Posted 29 December 2011 - 10:22 AM

If shimming the pressure relief plunger spring does'nt work it sounds like its down stream from the pump .
I feel for you I had a simmilar problem and it turned out to be liffters the new set i bought for my new engine passed way to much oil to the top end.
At cold start (over night) the oil could be seen at the rockers almost straight away when hot it was splashing every where when the cap was taken off the rocker cover . So i got the lifters out of my old engine refaced them splongked them in and now at idle when cold 50psi and hot 25 psi 1000rpm was 30 cold and 10 hot.bearings 1.5 thou rods and 1.75 thou on mains.
Liffters were sent back to the dealler who said they tested to spec and could not explain my symptoms .
Engine now running for over a year with no oil supply probs.Mybe worth a look.
Hope you sort it , Cheers ,Geoff

#48 _WYLDLC6_

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Posted 29 December 2011 - 10:41 AM

yeah discussed lifters. mechanic checked each one individually and found them to be ok. Im considering just changing them anyway, as i know he brought a new set the other day. They are the type that is supposed to restrict the amount of oil that passes but maybe they could be passing too much. He's got me another pump to try and i'll discuss the lifters with him when i pick the pump up.
Cheers Chris.

#49 73TORANA!

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Posted 29 December 2011 - 11:27 AM

A friend of mine also had oil issues and went through 3 lifter sets before he got some good ones . The ones out of my old engine came from Wade in Huntingdale via post Cod .

#50 _WYLDLC6_

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Posted 29 December 2011 - 11:35 AM

I think the ones my mechanic got for me are just crows. Not sure what brand are in there now but maybe worth looking at another brand in the future if no luck with other things.




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