Compression test help
 

Hey Pelicans, I want to do a compression test but I can't find my fuel pump fuse or relays to remove. I understand I need to deactivate my fuel pumps to do a compression test. My car is a 1975 911 with an 89 3.3 turbo using CIS and a Tec1 Ingition system. My fuse box shown below has a blown fuse in it where the fuel pump fuse is supposed to be. So that's not killing the fuel pumps.

There are two relays in the engine compartment that look like they were installed with the Tec1, see where my thumb and pinky are pointing. are these fuel pump relays? Do I just unplug the wires to these to stop the fuel pumps?

http://forums.pelicanparts.com/uploa...1457312415.jpg
http://forums.pelicanparts.com/uploa...1457312438.jpg

You not got much relays up front no more. So very after market wiring. Hard to diagnose that.
Your fuel pumps presumably are still fused somewhere. Why not run the engine and either pull fuses or those relays, til the pumps stop?
Alan

I can't run the engine, the intercooler, turbo and exhaust is all removed and rocker covers off, I can only turn it over. Maybe i'll just removed wires from the fuel pumps.

I've thought better of doing compression test with no oil. Will do leak down after engine is out.

Leak down better I think. If you are pulling the engine, all good. Easy. I have done them with engine in place without too much issue. Not much different to pulling spark plugs. You will need to be able to lock the engine on the stand when you do it - you don't want it flying around on the stand. Altho I have never had one want to do it - I make sure I am at TDC - probably helps.
Alan

Do both, comp. first, then if something fishy do the leak down.

pull yellow rly at the rear.