Stopping it firing to do a compression test.....

[simonbuk]

Whats the best way to stop an S2 from firing in order to do a compression test ?

I pulled fuse 3 which i thought was the fuel pump fuse - but it still primed and ran.
I pressed the inertia button behind the seat but makes no difference.
I pulled all 3 fuses by the inertia switch which makes no difference.

I hear the fuel pump prime everytime ?

[simonbuk]

Relay by the inertia switch ....... on an S2.

[mattdovey]

I pulled the inertia switch the other week and the thing stopped running pretty quickly. Pushed it in and it started to run again.
If I was doing a compression test, I'd just pull the leads off the plugs. Then remove the plugs. Not going to run after that I dont think.

[FunElan]

agreed^^ pull the leads off the plugs, leave the plugs in except the cyl you're testing

[Tuga2112]

i always do both. remove th leads and let it die after using the inertia switch.

belt and braces!

[simonbuk]

Are people talking about SE's ??

[dapinky]

Are people talking about SE's ??

SE & S2 will be the same.... as with many things, there are various ways to do it.

Personally, I'd flip the inertia switch with the engine running until it cuts out, then simply take out all 4 plugs so as to reduce the strain on the crank whilst turning it over to get the compression reading..... also allowing any small amount of injected fuel to be able to vent easily and not flood the remaining plugs.

On an NA it is even simpler, just remove the centre lead from the coil to the distributer and job done.

[Tuga2112]

On an NA it is even simpler, just remove the centre lead from the coil to the distributer and job done.

you can have the same effect by disconnecting the HES plug in the SE/S2.
Still i think the intertia switch is the best "first" step.
making sure theres no petrol seems safer than trying to avoid a spark. even with the plugs disconnected static electricity can cause a spark,if theres no petrol fumes nearby, you can add a few extra zeros to the risk %