Low oil pressure
#51 _Drag lc_
Posted 29 December 2011 - 12:13 PM
#52 _WYLDLC6_
Posted 29 December 2011 - 12:24 PM
Cheers Chris.
Edited by WYLDLC6, 29 December 2011 - 12:36 PM.
#53
Posted 30 December 2011 - 06:10 PM
#54 _oldjohnno_
Posted 30 December 2011 - 06:45 PM
Hi Ive always used standard volume pumps on my rebuilds , but the last couple of 6s ive done had standard jp brand oil pumps on them and had similar problems as yours . After a whole lot of hair pulling out and mucking around found that the oil pump internal clearances where way to big !! pump gears to body should be 2 to 2.5 thou the jps where 4 to 5 thou . end gears float to cover plate with gasket on was at 10 to 12 thou should have been 2.5 to 3 thou to tops . Fully blueprinted pump using holden original specs and clearances fixed problem straight away. also i noticed you said you shimmed pump about 1 mm this needs to be about 3 to 6mm then you will see a difference !!!! Reworked pumps 15 to 20 psi hot at idle 40 to 55 psi on at highway speeds . Hope this helps !!!!!
Fair enough, but it has already been tried with a known good pump with no change.
And pressure testing the entire assembly won't show anything because there are no faults on that side.
As I've said before I really really think you need to be looking at the suction side ie. the pickup and sump. If there are no obvious faults then I'd be trying a stock sump and pickup and then running the engine on the shop floor.
#55 _WYLDLC6_
Posted 30 December 2011 - 06:46 PM
Is it actually possible to shim a pump that far, because if so i'll definately give it a go.
Have noticed though that there is no pressure loss under acceleration, it does go up just not above 30 psi.
Cheers Chris.
#56 _WYLDLC6_
Posted 30 December 2011 - 06:55 PM
We may also be looking at changing lifters aswell before engine comes out, last resort lol.
Cheers Chris.
Edited by WYLDLC6, 30 December 2011 - 07:01 PM.
#57 _oldjohnno_
Posted 30 December 2011 - 07:02 PM
#58 _WYLDLC6_
Posted 30 December 2011 - 07:04 PM
#59 _Sandman_
Posted 31 December 2011 - 10:34 PM
If your pulling the engine again, you will be able to measure how far from the bottom of the sump the pickup is. It should be 10-12mm. Any closer and you will have problems.
I measure them using a straightedge across the top of the sump, then measure down off the bottom of the straightedge to the bottom of the sump. Write it down.
Then put ruler across the bottom of the pickup. Make sure it's parralell to the bottom of the block. Measure down from the ruler to the block. If you measure to both sides, the readings should be the same if the ruler is paralell.
If the sump was 200mm deep, then you want the pickup 188 - 190mm.
Sometimes when engines are getting shifted around, the sumps get dented and close this clearance up.
#60 _CHOPPER_
Posted 01 January 2012 - 12:02 AM
#61 _Sandman_
Posted 05 January 2012 - 05:56 PM
It can be hard to pick as a problem sometimes, because it might have enough clearance to supply oil ok at lower rpm, then loses pressure as the rpm climbs. It depends on design of pickup as well, but is always worth checking when assembling an engine.
#62 _WYLDLC6_
Posted 11 January 2012 - 04:40 PM
Pickup seems to be tilted back so front opening tilted down which may have only been 8 or so mm from sump. As the angle it was on
measured about 14mm from the half moon thin plate on bottom of pickup using sandmans method.
Ive removed pickup and done a dye penetrant check on it and found no cracks, maybe only a couple of pin holes in solder but dont think they go through.
Ive now put pickup back on engine and straightened up so that the face is parallel to the block and using some blue tac set it at aroun 12 mm from sump.
Does this sound right.
Should i still go with another sump first and check.
Cheers chris
#63
Posted 11 January 2012 - 05:30 PM
When i got back we dismantled the j.p pump and couldnt see any reason for it. I fitted a n.o.s std holden pump and used hpr40 oil and now have 32 psi at 110km and 22 at idle. If i rev it it goes upto 32 psi and nothing over. I have been told that is normal as thats where the releif valve opens. Hope this helps
Darryn
#64 _WYLDLC6_
Posted 11 January 2012 - 06:08 PM
Cheers Chris
#65
Posted 11 January 2012 - 06:14 PM
Darryn
Edited by gtr_161, 11 January 2012 - 06:17 PM.
#66 _oldjohnno_
Posted 11 January 2012 - 08:11 PM
And gtr_161 - your "engine builder" is bullshitting you.
#67 _WYLDLC6_
Posted 12 January 2012 - 05:21 AM
I think i'll just change it anyway, atleast i'll know one way or another.
With the dipstick it hits one of the welded plates inside the sump that stop the oil splashing inside then when the engine runs something hits it and pushes the dipstick out so i only use it to check the level.
Cheers chris.
#68 _Bomber Watson_
Posted 12 January 2012 - 07:19 PM
speedway engines.
Theres the two words that should make you walk out of any engine builders shop....If they advertise they build them, run away.
#69 _oldjohnno_
Posted 12 January 2012 - 07:59 PM
And that's just the women...
#70 _Bomber Watson_
Posted 12 January 2012 - 08:02 PM
#71
Posted 13 January 2012 - 12:25 AM
. Lol sounds like there are some numpties/turkey's up rockhampton way eh?Yep and they manage to talk up being able to spin the tyres on wet gravel and make it seem impressive, that must take some practice considering i can get my pushbike to do it!!!
#72
Posted 13 January 2012 - 10:11 AM
I think in the old days, speedway engines meant ALOT more than it does today, We just run slap togethers with big compression, big cam etc. Pity we are restricted to 2 barrells of OEM fury....
and we race on clay bomber, not gravel! haha
#73 _oldjohnno_
Posted 13 January 2012 - 12:04 PM
One of the racers had a breakage and an announcement was made that he needed a particular part (an axle I think) to continue. Next thing you know half the spectators rush out into the car park to pull the axles from their family cars to help out so old mate was able to keep racing. But the thing that stuck in my mind was how it seemed every second driver had big truckdriver/Elvis style sideburns...
#74
Posted 13 January 2012 - 12:35 PM
There is still a relatively friendly atmosphere compared to the drags, but the sprintcar thing has turned into a V8 supercar style of class, heaps of them think they are gods gift, those with too much money think they somehow classify for more benefits than those without etc.
Heaps of nice folk there still, heaps of toothless hillbillies and bogans too! lol
#75 _oldjohnno_
Posted 13 January 2012 - 01:32 PM
Heaps of nice folk there still, heaps of toothless hillbillies and bogans too! lol
Wall to wall flannelette always makes me feel at home..
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