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

[rcx132]

I don't want to mess up a good engine so I thought I best ask...

My buggy uses the chassis and running gear from a Suzuki SJ413 / Samurai, which is a solid axle based car. But I've fitted the engine from a Suzuki Vitara / Sidekick. It's same engine family so it bolted straight on (almost). I had to use the sump from the original engine though, as the Vitara engine is originally a front sump to get around the independent suspension, whereas the buggy needs a rear sump.

So now, what do I do to determine the correct oil level?

For now I've just poured in the recommended quantity for the engine. Though I'm conscious the new sump is smaller.

 

[RichardM]

Dip stick?

 

[Agrismith]

Take both sumps off.
Fill both with oil and poor into measuring jug separately.
Work out the difference in volume.
Subtract difference in volume from total original oil capacity

 

[brightspark]

Dip stick?

no need to call him that

 

[RichardM]

no need to call him that

I did think I should qualify the comment which is why I put the question mark in!

 

[brightspark]

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

 

[sasquar]

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.....

 

[Memmeddu]

Why not fit a dry sump?

 

[Keithmac]

Use the original dip stick for the engine block you've fitted.

You don't want too much oil in (level too high), if the crank can whip the oil up it will aerate it which is not good at all..

 

[8ob]

I dont think he can use the original dipstick unless the block has drillings for both front and back applications.

Bob

 

[Ubique]

What is the fill quantity for the engine the sump was donated from? Personally if it's the same engine family, I'd use that quantity.
Also bear in mind the cold quantity on a dipstick (if possible in your application) should be no more than 3/4 to allow for expansion when at running temperature.

 

[Smallfry]

Can you not use the original dipstick in the new engine, or is the tube length or arrangement completely different.

Too much oil will do the engine no good at all.

 

[reb78]

I was tbinking to use the original dipstick too. Surely the height of oil is what it really measures and we talk in volume as its relevant to the height a set vokume achieves? As above it needs to be the correct height to the crank and pickups i would think?

 

[Barking Mat]

How much oil should the engine take ?

Fill as above, mark dip stick, continue.

 

[Keithmac]

If you put a lower capacity sump on an engine you cannot use the OEM oil quantity for that engine.

 

[Ross365]

What is the fill quantity for the engine the sump was donated from? Personally if it's the same engine family, I'd use that quantity.
Also bear in mind the cold quantity on a dipstick (if possible in your application) should be no more than 3/4 to allow for expansion when at running temperature.

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?

 

[minimutly]

What is the fill quantity for the engine the sump was donated from? Personally if it's the same engine family, I'd use that quantity.
Also bear in mind the cold quantity on a dipstick (if possible in your application) should be no more than 3/4 to allow for expansion when at running temperature.

Eh? Expansion? You mean aeration? The actual increase volume due to expansion of oil, whilst I've never calculated it will be tiny, OTOH, the amount of oil lingering in the head with the engine running will be substantial, relatively.

 

[minimutly]

I was tbinking to use the original dipstick too. Surely the height of oil is what it really measures and we talk in volume as its relevant to the height a set vokume achieves? As above it needs to be the correct height to the crank and pickups i would think?

Yes. This is what you need, level relative to the crank is everything. If you end up with less oil you may want to investigate a winged sump or an oil cooler? If you plan on it getting really worked up.

 

[Nomad]

I've no experienced with Suzuki but on early Ford Crossflows - it's a simple job to swap front & rear bowl sumps, you just have to make sure you swap the matching oil pickup pipe at the same time.
Are Suzuki the same? Can you just swap the original pickup pipe onto the new engine before fitting the original sump?

I'd like to know the oil level in the new sump is the same as in the old one. Can you remove both sumps then -
Pour req'd amount of oil into the original sump and measure how far the level is below the top of the sump.
Pour same amount into the new sump and measure how far it is below the top.

If you get the same measure on both sumps - perfect !
If level in the new sump is lower than original, add oil to bring level up. When it matches, measure how much oil it used - that's your new fill quantity. Remark the dipstick to suit.
If level in the new sump is higher you have a problem as crank will always be fighting through the overfilled oil level (wing extensions needed on the sump to lower the oil level?)

If the oil level is low you risk oil starvation, if it's too high you lose power and I'd expect to blow seals.

 

[Ubique]

Eh? Expansion? You mean aeration? The actual increase volume due to expansion of oil, whilst I've never calculated it will be tiny, OTOH, the amount of oil lingering in the head with the engine running will be substantial, relatively.

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