|
V8 Vum
Original Poster
2,546 posts
90 months
|
I am quite concerned about the lack of oil level indication with the LS7 arrangement. There is no dipstick, no sight guage and very little concrete reliable advice it seems on the correct amount of oil if you have an oil cooler.
It seems that 8 quarts is the suggested amount on a Z06 with no oil cooler and it seems to suggest that the production car does have a dipstick (to what?). Is that right?
It has been suggested to me that the Oil tank position is not critical (higher or lower), and that you should use the gauze insert as a level guide inside. BUT I cant see that is right? It would depend on the hight of the tank in relation to the engine surely, and should it be hot or cold?
If overfilled, there are lots of horror stories about frothing and at worst I would have thought the seals would blow!
So what is the correct way of measuring the right amount of oil on these things?
Advice please?
|
|
|
Mr.Snood
62 posts
50 months
|
That's roughly what I have/do:
Pressure between 4 - 4.5 bar (58 - 65 psi) when idle.
If pressure drops by hard cornering on track, add oil :[
|
|
|
alfasteve
285 posts
129 months
|
Mr.Snood said: That's roughly what I have/do:
Pressure between 4 - 4.5 bar (58 - 65 psi) when idle.
If pressure drops by hard cornering on track, add oil :[ I think this is actually waiting for the presure to drop than the damage has been done already. the safest way would be either drysump or an electronic level indicator. But in a car with such cornering speeds you need a propper lubrication system that works at the full operational loads A dry sump system is much cheaper than a engine rebuild plus the engine can be mounted lower in the car giving better performance I would go dry sump all the way
|
|
|
MarkWebb
768 posts
86 months
|
Erm with respect!
Oil pressure has nothing to do with it and he already has a dry sump!
|
|
|
macgtech
607 posts
28 months
|
We find the best approach is to start the engine, run it for 30s to a minute or so, turn it off, then check the level in the tank (should be just above the gauze). You need to do this for the oil that has migrated into the sump whilst its turned off to be pumped back into the tank.
You should always do this before topping up too since its easy to overfill if there is some oil in the sump, you will end up with oil leaking out the lid of the oil tank. We find it only takes 30 secs to a minute to pump all the oil out of the sump.
|
Advertisement
|
|
|
7litrebig
397 posts
80 months
|
For my LS7 install (with cooler), this is what I do when changing oil, based on my own research and talking with the factory. This assumes your tank is same / very similar to Ultima standard LS7 install regarding height / location.
Ensure the system is empty - via both sump plugs, and also empty the cooler by disconnecting top (rear pipe and using a small(clean) plastic tube to syphon the oil out. Also remove filter. You could also take out the tank lower bolt, but I've found this unnecessary. Stating the obvious, refit all drain plugs!
Fill cooler with clean oil, reconnect cooler pipe. Fill new filter with clean oil and fit.
Fill tank to approx 1.5 inches below the perforated plate in the tank (approx 6.5 quarts, maybe a bit more) Start engine - I let mine run until oil reaches normal temp ranges ( >70 deg C on tank lower temperature), then switch off and check per GM guidance, between 5 and 15 mins afterwards if I remember correctly. The level should be just below (approx 1 inch) the tank perforated plate. I made up a wire dipstick to gauge this. If on occasion I think I'll a little too much oil in, then I've just syphoned off a little from the tank.
I've never had any problems with this approach.
Regards
Paul
|
|
|
alfasteve
285 posts
129 months
|
Dear Mark,
Than I would advise to place a electronic level indicator in the oil tank
and my drysump has a pump with a oil air seperator
this will avoid the pump sucing air instead of oil
|
|
|
738 driver
1,187 posts
62 months
|
^ To be fair Gents if this is a stock LS7 system its a sort of half-way-house adapted dry sump arrangment.
As advised, run it briefly and check / set level immediately...... some schools do this when everything is hot too, ( racers if they are carrying minimal weight/ small expansion chambers)
|
|
|
Leogasp
61 posts
49 months
|
7litrebig said: Start engine - I let mine run until oil reaches normal temp ranges ( >70 deg C on tank lower temperature), then switch off and check per GM guidance, between 5 and 15 mins afterwards if I remember correctly. The level should be just below (approx 1 inch) the tank perforated plate. I made up a wire dipstick to gauge this. If on occasion I think I'll a little too much oil in, then I've just syphoned off a little from the tank. I agree, this is the right way to check the engine oil level!
|
|
|
macgtech
607 posts
28 months
|
Mr.Snood said: That's roughly what I have/do:
Pressure between 4 - 4.5 bar (58 - 65 psi) when idle.
If pressure drops by hard cornering on track, add oil :[ What sort of oil pressure are you seeing at high RPM - our new engine oil pressure seems to be a fair bit higher than the old one which strikes me as a little odd.
|
|
|
Storer
1,990 posts
84 months
|
Hi Jonny
Mine is 70psi when warm (at pretty much any revs) but only 35 at tick-over.
I haven't got it really hot yet as I am still easing the engine in.
I have an oil-over-water oil cooler which probably helps maintain a more consistent temperature (though I don't yet measure oil temp).
Are you at Oulton Park this weekend and if so how's it going?
Paul
|
|
|
Mr.Snood
62 posts
50 months
|
macgtech said: What sort of oil pressure are you seeing at high RPM My indicator goes from 0 - 5. When not idle the indicator is stuck at 5 bar.
|
|
|
Storer
1,990 posts
84 months
|
Mr.Snood said: My indicator goes from 0 - 5.
When not idle the indicator is stuck at 5 bar. 5 Bar is approx 70psi in old money. Paul
|
|
|
packman10_4
169 posts
63 months
|
Were still using the original oil tank off the speed six engine thats got the dipstick in , the bottom of the tank was removed moddified and welded back on when the LS7 conversion was done.
|
|
|
macgtech
607 posts
28 months
|
Thanks guys, The pressure in the new one is a touch high, though it needs running in so should be fine once its done a couple of hours and has undergone an oil change. Storer said: Hi Jonny
Mine is 70psi when warm (at pretty much any revs) but only 35 at tick-over.
I haven't got it really hot yet as I am still easing the engine in.
I have an oil-over-water oil cooler which probably helps maintain a more consistent temperature (though I don't yet measure oil temp).
Are you at Oulton Park this weekend and if so how's it going?
Paul Not at Oulton Park, we fitted a new engine after the failure at Snetterton which took a while to sort out, then we fired it up and the cam chain broke within seconds, so its been sent back to be repaired. Should be at Brands though in 3 weeks time assuming they get it turned round quickly enough. Jonny
|
|
|
Leogasp
61 posts
49 months
|
Mine is around 30-33 at idle (850rpm) when hot (road use).
|
|
|
UltimaCH
1,721 posts
58 months
|
macgtech said: Not at Oulton Park, we fitted a new engine after the failure at Snetterton which took a while to sort out, then we fired it up and the cam chain broke within seconds, so its been sent back to be repaired. Should be at Brands though in 3 weeks time assuming they get it turned round quickly enough.
Jonny Wow, looks like you are going through some very hard, unpleasant and unnecessary incidents. I hope the wheel of fortune turns to better times very soon (fingers crossed)
|
|
|
macgtech
607 posts
28 months
|
UltimaCH said: Wow, looks like you are going through some very hard, unpleasant and unnecessary incidents. I hope the wheel of fortune turns to better times very soon (fingers crossed) Thanks - quite a few freak incidents, hopefully we have used up all our 'bad luck' now and we can move onto better things!
|
|
|
Verde
391 posts
57 months
|
Mine is troubling as well. BTW, it's an LS7-powered car that I purchased from the builder/driver. It had almost 4K miles on it without failure, so I am quite confused:
When started from cold, the pressure hovers in the high 90's and occasionally over 100, setting off a default alarm on my RacePak dash;
After it's warmed, it stays in the 90's while driving but will hit 100+ if I put my foot down and
Will idle at 65 lbs or so.
This seems way off. So, a few questions:
If the oil level is too high, is it likely to create an elevated pressure condition (I didn't think so but have to ask)
Could this be a problem with the filter? Does it have a pressure bypass that is not functioning?
Doesn't the engine have a pressure bypass and shouldn't it function to preclude this reading?
Might the display be set to the wrong 'units' (just a thought)
Thanks, and hope this is not too much of a detour.
B
|
|
|
MarkWebb
768 posts
86 months
|
Overfill will not effect oil pressure. Most engines have a bypass system to keep oil pressure in check when oil is cold etc. If yours is a crate engine it is extremely unlikely to be the problem. I would suggest that you become 100% sure that dash/gauge calibration is correct before going any further.
|
|
