Overfilling LS7
Discussion
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?
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 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.Pressure between 4 - 4.5 bar (58 - 65 psi) when idle.
If pressure drops by hard cornering on track, add oil :[
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
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.
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.
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
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
^ 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)
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)
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!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.Pressure between 4 - 4.5 bar (58 - 65 psi) when idle.
If pressure drops by hard cornering on track, add oil :[
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
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
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.
Jonny
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.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
Jonny
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)Jonny
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!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
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
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.
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