How much engine oil
Discussion
Easy question this, I hope. For those with the 6.3 small block Chevy based engine from American Speed, what quantity of oil do you use to refill on servicing? My notes from American Speed suggest 7 quarts ie 14 pints. However 4.5 litres will easily bring the level up to the dip stick full mark, plus another 2 litres for the Accusump. I am wondering if the mark on the dip stick is wrong. The sump is the standard job which clears the chassis rail beneath by about 4mm. Any ideas? Also, the standard short gearbox is supposed to take 3.5 litres. Any variation on that and in particular, easy ways to fill the swine as it is a VERY slow job. Has anyone fitted a temperature gauge to the gear box?
ls there any way you can tell if there is too much oil, ie. so that the crank whips air into the oil?
interesting they should say 8qts to you. l have filled with 5 in the sump which indicates it is too full. When it appears to be correct according to the dip stick, it is easy to drop pressure by sudden stopping or a fast roundabout. Could also help explain the poor oiling of the engine prior to the rebuild.
interesting they should say 8qts to you. l have filled with 5 in the sump which indicates it is too full. When it appears to be correct according to the dip stick, it is easy to drop pressure by sudden stopping or a fast roundabout. Could also help explain the poor oiling of the engine prior to the rebuild.
I had a similar problem when I filled mine. AS had deliberately removed the marker on the dipstick so that I could fill with the stated 8qts and then mark the dipstick to this level. On some consultation with a local engineer this is believed to be on high side and may account for a lot of the oil burning. Aparently if it covers the crank it throws the oil up under the pistons which puts undue pressue on the rings especially before all beds in.
This is all somewhat technically beyond me and it would be nice to know what is the correct quantity to have as an oil level.
This is all somewhat technically beyond me and it would be nice to know what is the correct quantity to have as an oil level.
My engine cam with a dipstick with all the marks ground off it and instructions to fill with 7 quarts. On my initial fill I put in the 6.5 litres (ish) that was asked for and filed a nick on the dipstick.
In normal running I underfill by about a 1/2 a litre. There are instructions with the accusump that tell you exactly how much to remove from the sump. I've forgotten the procedure..I'll look it up tonight.
If you overfill (or totally discharge your accusump) then the engine smokes out of the LH bank (where the crank sweeps the oil up into). Doesn't seem like a good thing but I'm hoping it burns off OK... The accusump sucks the oil back in once the temp rises a bit.
In normal running I underfill by about a 1/2 a litre. There are instructions with the accusump that tell you exactly how much to remove from the sump. I've forgotten the procedure..I'll look it up tonight.
If you overfill (or totally discharge your accusump) then the engine smokes out of the LH bank (where the crank sweeps the oil up into). Doesn't seem like a good thing but I'm hoping it burns off OK... The accusump sucks the oil back in once the temp rises a bit.
Stig said:
I think your dip stick must be wrong.
My notes from AS say fill with 8qts and mark dipstick yourself as full.
Gary.
Does that include the Accusump though Gaz?
No Stig, Just engine.
I'm not sure why it's 8qts when others have 7?
Perhaps the type of sump that came with mine?
From what I remember, there are basically only two oil pans that will work with the Chevy and unmodified Ultima chassis. You can run a stock 5 qt chevy oil pan or a Canton pan that holds 7 qts. The canton pan is gold and has small side kick-outs. The accusump holds 3 qts, the oil filter around a quart, and the oil cooler around .5 to 1 quart. The chevy stock pan is somewhere around 6.5" deep I vaguely recall. The canton is 7.5" deep. I'm not sure why you would want to grind off the "Full" mark on the dipstick. A crankshaft spinning in oil at higher rpms looks like a taffy making machine and robs hp. Not to mention, the stock chevy oiling system is pretty good compared to most. Does need a little help from an accusump under full braking though.
Cheers!
-Mack
Cheers!
-Mack
davefiddes said:
My engine cam with a dipstick with all the marks ground off it and instructions to fill with 7 quarts. On my initial fill I put in the 6.5 litres (ish) that was asked for and filed a nick on the dipstick.
In normal running I underfill by about a 1/2 a litre. There are instructions with the accusump that tell you exactly how much to remove from the sump. I've forgotten the procedure..I'll look it up tonight.
If you overfill (or totally discharge your accusump) then the engine smokes out of the LH bank (where the crank sweeps the oil up into). Doesn't seem like a good thing but I'm hoping it burns off OK... The accusump sucks the oil back in once the temp rises a bit.
When you find your accusump instructions, please post the amount of oil to reduce by. l recall this but cant find the exact amount and it is not on the accusump web site.
As for oil being swept up, my undersatnding is that air bubbles are swept into the oil with the result that you have airated oil lubricating the bearings which is not a good thing.
Cheers Brian, fortunatly l had assumed 1 litre is one quart so l wasnt far off.
All l need to know now is how much should be reduced to accommodate the accusump, other than the amount the accusump contains.
l have the full size accusump which most do and l measured the amount of additional oil drained from the car following draining the sump and then releasing accusump oil. lt was about 2 litres.
All l need to know now is how much should be reduced to accommodate the accusump, other than the amount the accusump contains.
l have the full size accusump which most do and l measured the amount of additional oil drained from the car following draining the sump and then releasing accusump oil. lt was about 2 litres.
ultiman said:
When you find your accusump instructions, please post the amount of oil to reduce by. l recall this but cant find the exact amount and it is not on the accusump web site.
I dug them out. It turns out that they are not particularly scientific. As a maximum Canton recommend filling to the normal MAX mark on the dipstick once the accusump has fully filled. They suggest that you can also reduce the oil level by up to the maximum capacity of the accusump (3 quarts).
Somewhere between seems like a good compromise.
The dipstick is marked to represent a height above which you do not want oil as it will come into contact with the crank.
When the engine is running the level will be lower as a proportion of the oil is now circulating the engine.
If (with engine off) you fill to less than the normal mark I fear that the level will be dangerously low with the engine running.
In all of this I believe you should regard the Accusump as being full at all times as, apart from startup, it will only empty when all your oil is in the wrong place!!!
Steve
When the engine is running the level will be lower as a proportion of the oil is now circulating the engine.
If (with engine off) you fill to less than the normal mark I fear that the level will be dangerously low with the engine running.
In all of this I believe you should regard the Accusump as being full at all times as, apart from startup, it will only empty when all your oil is in the wrong place!!!
Steve
Steve
I disagree. The oil pressure charging the accusump changes when the engine is hot and cold. Lovely 4-5bar when cold at idle and then after an hour of good thrashing it will drop to 2-3 bar at idle. This will then change the pressure of oil on the accusump piston and the from this the amount of oil stored.
Have I got this wrong?
I disagree. The oil pressure charging the accusump changes when the engine is hot and cold. Lovely 4-5bar when cold at idle and then after an hour of good thrashing it will drop to 2-3 bar at idle. This will then change the pressure of oil on the accusump piston and the from this the amount of oil stored.
Have I got this wrong?
bluesatin said:
Steve
I disagree. The oil pressure charging the accusump changes when the engine is hot and cold. Lovely 4-5bar when cold at idle and then after an hour of good thrashing it will drop to 2-3 bar at idle. This will then change the pressure of oil on the accusump piston and the from this the amount of oil stored.
Have I got this wrong?
The piston in the Accusump is held in the empty position by only 7psi (0.482633 Bar) of air behind it.
As soon as the engine produces more oil pressure than that the Accusump will fill to capacity.
Steve
steve_D said:
As soon as the engine produces more oil pressure than that the Accusump will fill to capacity.
Guy's got it right. The amount of oil in the accusump depends on the current oil pressure (roughly - the friction in the pipes and the size of the valve orifice will damp the system). I guess the preload ensures that the accusump fills to about 1/2 full at normal engine pressures. It's never going to be particularly precise though.
If you're feeling a bit
then it should be possible to do the maths to convert the pressure shown on the gauge to the amount of oil in the sump at any given moment. It'd have to be a pretty boring night on the telly... 
It sounds as though you are probably all correct. I have found the same as Guy, in that the accusump will discharge where there is low pressure and will recharge again depending on the oil pressure at the time. I usually check the pressure when I have turned off the engine as my accusump sits behind the bulkhead so I can easily see the gauge through the engine vents. Where the oil is hot and running at lower pressure, it will not charge it up to 5 bar, only what is shown on the pressure gauge on the dash. I now have an oil pressure switch on the earth from the electric valve so that the accusump wont discharge until the pressure drops to 2 bar. Otherwise it could only contain low pressure oil when I need it most. The theory is that it will contain oil at 5 bar and when I hit 2 bar, the lot will be released.
I think I have the answer to the low pressure problems anyway and that is lack of oil in the sump due to a wrongly marked AS dipstick!!
I think I have the answer to the low pressure problems anyway and that is lack of oil in the sump due to a wrongly marked AS dipstick!!
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