DIY - Changing the CTSC Autorotor oil

MvM

Legendary Member
Joined
12 February 2002
Messages
3,021
Location
Rotterdam, Netherlands
This week it was time to change the oil in my my Comptech Autorotor Supercharger.
And although the procedure is not difficult, I tried looking it up on this forum but could not really find a good explanation for it. So I decided to make one myself.

First to remember is that the oil in the supercharger is NOT the same oil as you use in the NSX engine.
Instead, for the Autorotor, a 20W50 oil is recommended and for this, a bought a liter of this oil to be used specifically for the CTSC. The CTSC only uses a very small amount of oil, about 110 centiliter (3.5-4.0 oz), so one bottle will last a long time.

The tools needed are very basic.
You will need a way to get the oil out of the CTSC through the same hole you use to poor in it.
I use a plastic siphon with bellow and a narrow plastic tube that I picked up in a car toolshop. Many people use a turkey baster, but I could not find one and this works just as well.
Second, I use a paper or plastic cup that I have marked with a pen at the 110CC level. If you have a kitchen scale, this can be easily done beforehand.
Third, you need a small funnel to get the oil in without spilling any.
To catch the old oil, I use an empty plastic milk bottle.

CTSC-Oil1.jpg


The tools:
1 liter of 20W50 oil
1 plastic ciphon with bellow and thin plastic transparent tube
1 clean paper cup which is marked at the 110 Centiliter level
1 empty plastic milk bottle
1 funnel for pouring the oil

CTSC-Oil2.jpg


To remove the oil, unscrew the oil dipstick on top of the supercharger and remove it.

CTSC-Oil3.jpg


The dipstick of the supercharger removed.
Please note that on the dipstick, there are two clear marking for high and low oil level.

CTSC-Oil4.jpg


Put the hose of the siphon all the way into the dipstick hole.
Make sure it reaches all the way to the bottom.

CTSC-Oil5.jpg


I find that when the tube is still empty, the bellow on the bottom end does not have enough power to suck the oil up. So I started with sucking the oil up myself. The clear tube makes it easy to see the dirty oil coming up and to prevent getting any of it in your mouth. Once the tube is almost full, the bellow can do its work.
Or, alternatively, you can remove the tube and blow the oil into the milk bottle yourself and repeat these steps until all oil is removed. It's only small amount after all.

CTSC-Oil6.jpg


I fill the paper cup with fresh oil up to the level I marked with a pen beforehand.

CTSC-Oil7.jpg


Poor the oil into the supercharger and wait until all oil has found its way into the CTSC.

Wipe the dipstick, insert it and check if the oil level is correct,
(If you marked the cup well, it should be about 2.5 cm (1 inch) on the dipstick.)

Wipe away any spilled oil and clean up and you are ready to go.
In all, this takes about 10-15 minutes and so it certainly is not a difficult job.
 
Last edited:
I was told that a ctsc never needs oil changing but I say why the hell not. Thanks for the detailed advise. Fyi, worst thing ever for a ctsc is overfilling with oil.
 
I was told that a ctsc never needs oil changing but I say why the hell not. Thanks for Fyi, worst thing ever for a ctsc is overfilling with oil.

You are right there is no specific oil change interval given for the CTSC, but it is said to change it when the oil appears to be dirty.
And yes, overfilling is definately not a good idea. That's why I use an exactly measured amount of oil.
 
Good write-up. Some remarks:
- The blower dipstick is pretty useless for reading oil levels. I've a modified one where the oil level can be identified 1000 times easier.
- Use motorcycle oil. It will be fully synthetic 10W/50. 50 is the number to look at. This oil is meant for high-reving components. Most of the oil in 20W/50 over here are mineral oils, not synthetic. I recall the earlier blower needing different oil weight.
- I change it with every engine oil change.
- I went to the phamaca and got the biggest syringe they had (100 ml), the pretty easiest way to suck it out with a small hose.
 
Good write-up. Some remarks:
- The blower dipstick is pretty useless for reading oil levels. I've a modified one where the oil level can be identified 1000 times easier.
- Use motorcycle oil. It will be fully synthetic 10W/50. 50 is the number to look at. This oil is meant for high-reving components. Most of the oil in 20W/50 over here are mineral oils, not synthetic. I recall the earlier blower needing different oil weight.
- I change it with every engine oil change.
- I went to the phamaca and got the biggest syringe they had (100 ml), the pretty easiest way to suck it out with a small hose.

I wanted to get a syringe first, but couldn't find one big enough. Then I bought the oil (synthetic) and this autoshop had these siphons on sale for a few euros and I thought it might be useful for this and perhaps other purposes as well.
The siphon's tube alone is voluminous enough to catch all the oil in to careful sips.
 
Do you need the same weight oil for the whipple SC?
 
Thanks Ric!
 
So I finally got around to changing my autorotor oil, but there appears to be conflicting info for how high to fill. The instructions say to fill to 1" of coverage on dipstick. 1" of coverage is just slightly below the bottom mark on dipstick. Should I fill to 1", or slightly higher to be between the 2 marks? Right now I'm exactly at the bottom mark after filling with fresh oil. Should I suck some out?

I realize I'm likely being overly paranoid, but hey, it's an NSX.image.jpg
 
So I finally got around to changing my autorotor oil, but there appears to be conflicting info for how high to fill. The instructions say to fill to 1" of coverage on dipstick. 1" of coverage is just slightly below the bottom mark on dipstick. Should I fill to 1", or slightly higher to be between the 2 marks? Right now I'm exactly at the bottom mark after filling with fresh oil. Should I suck some out?

I realize I'm likely being overly paranoid, but hey, it's an NSX.View attachment 124231

You didn't mention which CTSC model you have. I added about 100cc to the SC and it was right at the correct level.
Perhaps your dipstick is a little longer than usual.
 
Is anyone here running royal purple in their ctsc? Oil is hard to check levels on even with a white towel. I used to run royal in my old preludes and loved it. I just hated how it burned and I always needed to add. So it has been nothing buy Mobil 1 in my x. But being it is purple and does not come in contact with combustion, it shouldn't burn. Anyone else running royal in the blower please chime in.
 
Jinks, I was using RP before. Recently, I've switched to Amsoil. I have the old Flintstones edition Whipple :)
 
Did you displace the amount, or added it on top of the normal fill?

I also used a cap full of RS*R Ran-Up in mine.

My boost peaks at 7.8psi and stabilizes at 7.1-7.3psi at sea level. It use to peak at 7.1.
 
Back
Top