How should I determine sump oil level after a customised sump?

[Ubique]

Re the oil getting hot, you seem to be suggesting that hot oil occupies 33% more volume than when cold; that's very much more than I think is true.

I think it would be good to have a drawing or sketch on the new configuration which would show how far the crank goes in below the top of the sump and how far the pickup pipe goes in, and a good oil level (at least as a starting point) might be halfway between the two?

It would depend upon the design of the sump, if the bulk of the oil is in a section with a small footprint, then clearly the hot level will be higher than a sump with a larger footprint. It's common across a lot of vehicle manufacturers to specify the cold fill level to be at the 3/4 point on the dipstick, the 'maximum' point is just that, which is completely different to 'full'.

 

[sako243]

If you still have the original sump put it back on with the original dipstick. Measure the protrusion of the dipstick below the bottom of the block to the two levels and then transfer across to the new sump. Might need to get inventive if the sump holds the dipstick tube.

Level wise you want it sitting about the same place so the crank can throw it about but not stir it to a froth. You'd ideally want the same volume as well so that the cooling requirements are meet along with ensuring you have enough oil to fill all the pipes, head, oil channels etc.

 

[8ob]

The word "buggy" rings of something being spanked around a track, might be worth dropping the sump and modifying it to suit the application. As a minimum I would start by adding some capacity , a windage tray and calibrate the stick while its off. Where`s @PhillipM when you need him?

Bob

 

[minimutly]

Probably both expansion & aeration. On engines I work with on a daily basis it's enough on a fill quantity of 5.8 litres to push the measured level from 75% at ambient to near 100% at running temperature and the sump is physically quite large,. If the fill quantity is 6.0 litres, then it is enough to cause an overfill warning when at running temperature, large return oilways in cylinder heads and blocks coupled with low viscosity oils mean a quick return to sump. Regardless, the OP needs to have a like-for-like fill level, there's many good suggestions above on how to achieve that.

ETA - a handy little calculator for you. https://www.engineeringtoolbox.com/volumetric-temperature-expansion-d_315.html

Yep, this gives a 0.05 gallon increase at 90 degrees. I didn't do it in mm height, but would guess at a few mm
As you say it depends on the surface area of the sump, might be as little as 3, or as much as 5mm.

 

[not done it yet]

The word "buggy" rings of something being spanked around a track, might be worth dropping the sump and modifying it to suit the application. As a minimum I would start by adding some capacity , a windage tray and calibrate the stick while its off. Where`s @PhillipM when you need him?

Bob

Yes, more to it than just the level - although that should not be exceeded.

‘Full’ marks on dipsticks are just that. The engine manufacturer will have already marked the dipstick having taken into account the ‘maximum’ safe limit. Baffles, to prevent oil-wash, might be among changes/additions required, if being used at excessive angles/speed changes, etc. Or dry sump for even more-extreme conditions of operation.

I know of one particular engine design where the number of failures (often catastrophic) was a relative disaster for that company. While the oil level in the sump was not altered, the sump capacity was eventually increased (by some 25%?), an oil cooler circuit was added and (much later) there were other internal modifications to the engine. The design worked reasonably well at around 80HP but was a veritable disaster when ‘uprated’ to over 100HP.

 

[minimutly]

Yes, more to it than just the level - although that should not be exceeded.

‘Full’ marks on dipsticks are just that. The engine manufacturer will have already marked the dipstick having taken into account the ‘maximum’ safe limit. Baffles, to prevent oil-wash, might be among changes/additions required, if being used at excessive angles/speed changes, etc. Or dry sump for even more-extreme conditions of operation.

I know of one particular engine design where the number of failures (often catastrophic) was a relative disaster for that company. While the oil level in the sump was not altered, the sump capacity was eventually increased (by some 25%?), an oil cooler circuit was added and (much later) there were other internal modifications to the engine. The design worked reasonably well at around 80HP but was a veritable disaster when ‘uprated’ to over 100HP.

Indeed. My Rover m16 (a 16V head on the montego 2 litre effectively), when raced hard would allways wipe its big ends. For a long time I never worked out why, until one day testing on my dyno, full chat for getting on for a minute, it exhaled half the sump contents out of the cam cover breather..
Pootling allong the oil would run happilly down the drains into the sump, full chat was another matter. Vauxhall 16V engines have the same issue, and I know of one clever Ferrari engineer that used to race a turbo'd PRV6 - he had the same be bearing issue, until he realised how much oil was getting held back in both heads.
Sometimes the fix is clever pipework, sometimes it's a dry sump?

 

[Morris]

The word "buggy" rings of something being spanked around a track, might be worth dropping the sump and modifying it to suit the application. As a minimum I would start by adding some capacity , a windage tray and calibrate the stick while its off. Where`s @PhillipM when you need him?

Bob

What Bob said. I do this for warmed over road cars , I would certainly like better for anything Motorsport.

 

[PhillipM]

The word "buggy" rings of something being spanked around a track, might be worth dropping the sump and modifying it to suit the application. As a minimum I would start by adding some capacity , a windage tray and calibrate the stick while its off. Where`s @PhillipM when you need him?

Bob

On holiday

 

[rcx132]

Dip stick?

Which one would you use? The one made for the block or the one made for the sump?

As others have pointed out, the oil system has now changed, using a random dipstick might not be safe.

 

[PhillipM]

The one for the block as that's the one that matches up with the crank windage. Whether that leaves you enough oil in the system for pickup after draining down however is another matter. As someone else said, fill the sumps to the same level from the face and check see if the capacity is similar.

And yes, definately baffles at the least if you're doing any comp.

 

[RichardM]

Which one would you use? The one made for the block or the one made for the sump?

As others have pointed out, the oil system has now changed, using a random dipstick might not be safe.

Block, as others have stated it is the designed oil height you need, splash, frothing etc. Check pickup location you may need to baffle the sump plate / put an oil gate in, to ensure oil at the pick up if accelerating quickly (early KZ1000 / 900s suffered from this).

 

[rcx132]

your also going to have to check the pickup pipe position the sump was at front now rear so all the oil will pile up at the back when you accelerate. worth thinking about

I moved the pickup already. There was another post about that experience a while back.

going off on a tangent here, but does this mean that the 1.6 16v vitara engine, bolts up to the sj gearbox?? i can feel a plan occurring if so.....

They are the same family of engine but two bolt holes dont line up due to size difference. Adapter plates are £50.

Why not fit a dry sump?

Ha at this stage I'm just looking forward to the thing moving under its own power. Ideas like dry sumps are a long way away and if I do that I may as well upgrade to a bigger and sportier engine.

 

[rcx132]

Ah the oil capacity of both engine's is the same after all, I should have checked before posting, I just went by how they looked. So just use the dipstick that belonged to the block, and job done

Answer may seem obvious but I just wanted to check with you all in case I missed something.

Thank you for all the input.

 

[Turbo]

Indeed. My Rover m16 (a 16V head on the montego 2 litre effectively), when raced hard would allways wipe its big ends. For a long time I never worked out why, until one day testing on my dyno, full chat for getting on for a minute, it exhaled half the sump contents out of the cam cover breather..
Pootling allong the oil would run happilly down the drains into the sump, full chat was another matter. Vauxhall 16V engines have the same issue, and I know of one clever Ferrari engineer that used to race a turbo'd PRV6 - he had the same be bearing issue, until he realised how much oil was getting held back in both heads.
Sometimes the fix is clever pipework, sometimes it's a dry sump?

The first all alloy Peugeot 1.9l MI16 engine built for touring car racing was basically a 16v head on a gti block. This suffered a similar problem with the oil unable to drain fast enough from the head resulting in oil starvation during cornering.
When I fitted one to a 205 I had the same issue but with a couple of fairly simple mods I sorted it. I fitted a baffled alloy sump from a 306 but kept the sandwich plate in place giving me an extra 1.5 litres of oil. I also fitted the oil pump from the later iron block engine & extended the pickup by 20mm.
I've seen several more complicated mods used in race/rally cars but most go the dry sump route.

 

[lincoln2013]

Ah the oil capacity of both engine's is the same after all, I should have checked before posting, I just went by how they looked. So just use the dipstick that belonged to the block, and job done

Answer may seem obvious but I just wanted to check with you all in case I missed something.

Thank you for all the input.

Hopefully that works out for you but now that the dip stick is no longer going in the pan it may foul the bottom before it is in. I built a similar buggy years ago with mainly Suzuki sj running gear & Vauxhall engine with a custom sump & pickup pipe to clear the diff.

 

[not done it yet]

Back in the ‘70s we used to cut the sump pans, turn them round and weld them up If an appropriate sump pan was not to hand. Oil pick-ups were modified likewise to fit, of course That was for Ford engines. One friend, back then, added extra capacity to his sump pan by welding on extra pockets. He worked at March Engineering (of racing fame) so engine mods and shortened prop-shafts etc were no problem for us.