Dry Sump Top Up Query

[steyning]

Hi - can anyone help out? My 1400K Series Caterham has a dry sump set up. There is the usual filler cap on the top of the rocker cover, though very tight and perhaps not for forcing, but obviously no dip stick to check. However, there is a second screw cap between the back of the engine and the bulkhead, above the clutch housing - presumably the oil filler. Looking inside no oil is clearly visible as a level, like water in a radiator say, but the sides are oily. To what level should I fill up to when doing regular maintenance checks?

[Paul McKenzie]

Filler cap on the cam cover is virtually redundant in a dry sump system, although it can still be used to quicklytop up oil particularly after an oil change.

 

The one on the bellhousing is what you need. Oil level should be just under the ledge baffle a few moment after switching off the engine. To be honest it's very dificult to check for there's plenty of leeway for error.

 

Paul

[shn7]

steyning,

 

You need to check the level just after switching the engine off before oil drains back to the sump. If you're checking it quite a while after it's been run then you won't see much oil in the bell tank. Best methaod is to make up your own dip stick from a piece of piano wire. Make a mark on it about 9" - 10" from the bottom. This is how much ought to be in the tank having just switched off. If you overfill, the excess will get blown out into your catch tank (you DO have a catch tank don't you?). DS systems will find their own level this way if overfilled.

 

When topping up use either cap. After an oil change I tend to pour some in each to ensure there's some oil at the top of the engine on startup. Though this probably isn't a major concern.

 

Steve.

Sussex (West) AR

Not forgetting Percy the Polar Bear who recommends

Puddle Pet Care

[steyning]

Thanks for your help both - just to check if I make up a dipstick, say 12 inches long, I need to place a max/min mark at 9 and 10 inches respectively ( zero being at the handle end of the stick). Thanks again

[shn7]

No, sorry you need to measure up from the bottom of the dipstick and then insert it until it touches the bottom of the tank. You are trying to measure depth of oil not surface level from the top of the tank IYSWIM.

 

Steve.

Sussex (West) AR

Not forgetting Percy the Polar Bear who recommends

Puddle Pet Care

[6speedmanual]

Steyning,

 

A 12" stick could fall into the tank!

 

25" length of 3/16" steel or ali rod is ideal raw material.

 

First thing is to insert it into the tank and probe it around the bottom of the tank until you find its lowest resting position (avoiding all the ledges and castings in the bottom of the tank). Mark off this level with the top face of the bell tank tower. Remove the rod and score or hacksaw a groove around the rod. With this depth marker you will NEVER wonder if you have hit the correct bottom position of the tank. On mine it is 22 5/8" from the bottom end.

 

Then all you need to do it make the MAX and MIN marks. My MIN mark is 13 5/8" down from the top which corresponds exactly with the MIN position on the CC supplied dipstick on the screw in cap. This happens to be equal to 9" up from the bottom of the tank/dipstick.

 

For the MAX mark, make another groove 1" up from the MIN mark. That is your 10" mark from the bottom of the tank.

 

The 1" gap between MAX and MIN equates to very close to 250ml of oil. Knowing this allows very accurate top ups to be made to hit the MAX level.

 

Minister Power recommend (FAQs) running at least 9 1/2" from bottom of tank so I keep mine near the MAX mark (10"). Since using this dipstick to control my oil level, my oil consumption (wasted) has been negligible compared with with the previosly used "overfill" technique often mentioned. Also means that my catch tank needs emptying far less frequently.

 

Finally, bend the top 1" of the rod over to make a small hook/handle for lifting and hanging the dipstick.

 

Job's a good'un.

 

Peter

 

 

BRAWNGP green SUPERLIGHT

FCITW 2009 😬

 

Edited by - 6speedmanual on 9 Aug 2009 14:09:20

[shn7]

Just one note on the above. Not all of us have the conning tower (with or without built in dipstick) and so all measurements need to be depth up from the bottom of the tank. Good point about finding the bottom though and marking at the top of the filler neck on the stick.

 

Steve.

Sussex (West) AR

Not forgetting Percy the Polar Bear who recommends

Puddle Pet Care

[MADMALC]

And remember once you have a base level keep topping up with a small amount until it blows the same ammount of oil back into the catch tank. Then you know it is at the optimum level.

 

S7MAD

[steyning]

Thanks all for the ideas above:

Then all you need to do it make the MAX and MIN marks. My MIN mark is 13 5/8" down from the top

After leaving the car for a while, I can actually see the bottom of the sump as my set up has, as Steve points out, no conning tower or built in stick, just a screw cap - how do you Peter calculate the minimum mark as a starting point, such as your 13 5/8" calculated above ? Sorry to be sounding stupid

[6speedmanual]

Steyning

 

On my car with "conning" tower, the 13 5/8" is the distance measured from the bottom of the screwcapcap with the dipstick attached to the MIN mark on the dipstick.

 

On yours without "conning" tower, to mark up your homemade dipstick rod I suggest you mark up the MIN 9" from bottom, the MAX 10" from bottom. For the DEPTH mark, get the dipstick fully in to the bottom of the tank and mark off level with the upper rim of where you screw the cap on. The Depth mark purely lets you know you have got the stick all the way in each time you use it.

 

P

 

 

BRAWNGP green SUPERLIGHT

FCITW 2009 😬