CIS back in now what.

[joe912/62]

Got the CIS back in the car, can I try to start the car to see how she runs or is
there something I need to do before hand?

Thanks

[Showdown]

Might be prudent to to a pressure test just to make sure everything is holding before you fire it up.

[rwest]

You really should put all of the injectors into jars and set the mixture to the factory baseline.

Doing this also verifies that the spray patterns are good, equal and bleeds the air out of the lines.

Hopefully someone chimes in with the procedure, if not I probably can dig out my digital manual and get you the info.

If memory serves, you get the injectors into clear glass baby bottles or mason jars with holes drilled in the lids, increase the mixture screw until they just spray and then back the screw off a half turn. This is just by memory, make sure you double check this with another member or manual.

Because you likely got rid of many leaks in the system you will need to set the baseline.

[rwest]

Oh, one more thing, have fire extinguishers nearby just in case!

[joe912/62]

I installed new injectors, do I still need to do this test?

[boyt911sc]

Originally Posted by joe912/62

Got the CIS back in the car, can I try to start the car to see how she runs or is
there something I need to do before hand?

Thanks

Joe,

Do a fuel pressure test. Do you know how to jumper terminal #87a and #30 for the FP relay socket? This is a basic knowledge a CIS troubleshooter should know. Do not even think of starting the motor if you have not done a fuel pressure test. Why? You don’t want to run or start the motor with fuel dripping over your exhaust. Test run the FP for 30 sec. or longer and look under the engine. Watch out for any sign of fuel drip on the floor. Keep looking around, top, side of the motor for any sign of fuel leak.

You should not fill the old tank more than 10 quarts of fresh oil at this point. 10 quarts are enough for start up. Disable ignition and FP by disconnecting the plug to the CDI and removing the FP relay and crank the starter for 3~4 sec. and stop. Everything sounds NORMALL? If yes, repeat cranking the starter a few more times to lubricate the internal parts of the motor in preparation for running the motor.

RWest gave you a good tip for adjusting the initial fuel mixture setting. You need to pull out all the fuel injectors out from the intake runners. Take your time and relax. You will be OK. Don’t forget that you need a fully charged battery. Recharged it if needed.

Other things I use for the initial start-up are:

• Inductive timing light.
• CIS Pressure gauge.
• Vacuum gauge.
• Mechanical pressure gauge.
• Smoke generator.

Tony

[timmy2]

Test is to confirm equal distribution of fuel flow and good spray patterns.
So yeah, do the test.

[joe912/62]

I didn't change the oil, I only removed the CIS to clean it up and change the fuel injector cups and injectors and changed the o rings. I also did the triangle of death. Everything thing else was reinstalled and in working order when they were removed. The car ran good before removing it.

[rwest]

Originally Posted by joe912/62

I didn't change the oil, I only removed the CIS to clean it up and change the fuel injector cups and injectors and changed the o rings. I also did the triangle of death. Everything thing else was reinstalled and in working order when they were removed. The car ran good before removing it.

Yes, but likely you had multiple vacuum leaks and the fuel system had been tinkered with over the years by adding more and more fuel to make up for the unmetered air and now it most likely will be very rich and might not even run or could run poorly, that is why it is recommended to put it back to the factory setting.

[boyt911sc]

Originally Posted by joe912/62

I didn't change the oil, I only removed the CIS to clean it up and change the fuel injector cups and injectors and changed the o rings. I also did the triangle of death. Everything thing else was reinstalled and in working order when they were removed. The car ran good before removing it.

Joe,

Put everything back together and I will give you the benefit of agreeing everything was good and working. Then you should have no problem getting it to start and run. Keep us posted.

Happy New Year!!!

Tony

[joe912/62]

If I jump the FP do I need to have the pressure gauge or try to see if there’s any fuel leaks without the gauge attached.

[boyt911sc]

Originally Posted by joe912/62

If I jump the FP do I need to have the pressure gauge or try to see if there’s any fuel leaks without the gauge attached.

Joe,

The pressure gauge is installed if you want to know and monitor the control fuel pressures, residual, and system pressures. Simply running the fuel pump creates fuel pressure in the system and fuel will appear or show at spots where the leaks are located. If you don’t have a gauge installed, how would you know the control fuel pressures? Suppose the motor would not start or run at all? How would you diagnose the problem?

I could not remember how many times I encountered loose fuel fittings or fuel leaks after turning on the FP. And as I get older and experienced, the incidents gets more frequent. Sometimes, I have the fuel hose total disconnected or the fuel fitting was only hand tighten. As a precaution, I run the FP very briefly and switch it off. This way, I could minimize or control the amount of time for cleaning the mess.

Good luck.

Tony

[joe912/62]

I would need to purchase a pressure gauge. So I would like to jump the fuel pump to see if there are any leaks before trying to start the car. If there are no leaks I would then purchase a gauge and test the system. Is that doable?

[boyt911sc]

Originally Posted by joe912/62

I would need to purchase a pressure gauge. So I would like to jump the fuel pump to see if there are any leaks before trying to start the car. If there are no leaks I would then purchase a gauge and test the system. Is that doable?

Joe,

Test run the FP and check for leaks. If there is no leak or fuel dripping to the floor, you could start the motor. Just double check for fuel leak in the engine bay. You don’t need a fuel pressure gauge to test run a motor. But you will eventually need one for diagnosing your CIS. Keep us posted.

Tony

[targa80]

Plastic baby bottles are cheap and reusable.

[joe912/62]

I have steel lines so doing that wouldn't work.

[boyt911sc]

Originally Posted by joe912/62

I have steel lines so doing that wouldn't work.

Joe,

The baby bottles will work even for steel fuel lines. Use your imagination to achieve your goal. You have to place the individual baby bottle near the fuel injector and secure it. And run the fuel pump.

Tony

[joe912/62]

What gauge wire can I use to make the jumper?
Also do I turn the ignition switch to the first position then switch on the jumper?

[Showdown]

14 or 16 gauge is fine. You can crimp on bullet connectors to the ends of the jumper wire to make fitting it to the relay socket easier, or you can just twist and solder the ends of the wire. You don’t even need to solder the end- you can just stuff it into the socket and it’ll work fine.

[Mark93077]

Originally Posted by joe912/62

I would need to purchase a pressure gauge. So I would like to jump the fuel pump to see if there are any leaks before trying to start the car. If there are no leaks I would then purchase a gauge and test the system. Is that doable?

I have a 1977 930 turbo. This test kit on Amazon had the connections needed to place inline between my fuel distributor and WUR to do all the tests mentioned. With my car just removing the plug to the cold start valve enabled the fuel pumps to run when the key gets turned part way so I did not have to bother with relay jumping. Then you can test with the WUR electrical plug unplugged to get cold pressure, then plug in wur to get warm pressure reading, then turn off and get residual pressure readings at 10 and 20 minutes to make sure they are above minimum. I can attach pictures of the setup
$60 for tester