'71 911E staring problems

[mr_force]

HI there, my dad and I got a '71 911E and restored it. It was parked for two years before we got it. When I cleaned up the engine the #3, and #6 cylinder intake was very dirty (my suspicion are they didn't get any fuel). We are now wanting to start it up but we are having a world of problems with it. At first it was timing, fixed, then fuel pump, fixed and checked pressure and its fine. Now we're focused on the mfi pump. The button on the back of the pump does depress easily, so I don't believe the issue lays souly there. Is there a way to check and clean the injectors? If anybody has any other ideas on what the problem can be I would greatly appreciate the advice.

Many thanks

[Porboynz]

But what problem(s) are you having? Hard to start? Will not idle? Will not run at full revs? Misfires at trailing throttle? Some cylinders not firing? All of these? Quick checks are the cold start relay and spray injectors, cold start rack and hot air hose from extractors, injectors blocked (swap with known working cylinder to see if its the pump or the injector) If its not running at all then you must be sure the timing is within spec first, fuel next. Compressions OK?

[mr_force]

The problem is we cant get it fired up, no matter how long, or how many times we crank it. Timing seems to be fine, we poured some gas down the in intake ports yesterday and she wanted to start but noting. We think its not getting any gas. the injector lines seem to have gas in but the injectors aren't firing.

[Rusty 356]

Pull a plug or two, the easy ones and check if too much fuel. Plumbing for the fuel lines correct from the filter.
Fuel pressure XX psi.
Fuel Flow xx/min.
Have you tried using any starting fluid, small amount.
Check stop solenoid
Good luck,

[Porboynz]

You say you got a few coughs by squirting raw fuel down the stacks? Thats a positive sign. An MFI engine will try to start on the fuel squirting out the cold start injectors while the engine is cranking, or if they are disconnected then use a aerosol can of starting fluid as suggested like the top fuel dragsters use squirted into the stacks while cranking. Squirting raw fuel from a squeeze bottle is tempting but dangerous, your car and your eyebrows are in imminant danger. If you are getting nothing, no kicks and coughs then back to the electrics, spark timing can easily be 180 degrees out. Do you have compression in all cylinders? The plugs will be wet after extended cranking if the cold start and main injectors are hooked up and working. Pull the plugs and look. Another thing is the shut off solenoid that stops back firing on a trailing throttle on over run, make sure you have not wired this incorrectly through the microswitch on the side of the lhs stacks. You can disconnect the wire from the solenoid on the MFI injection pump as a quick check or put a meter on it to make sure no 12V on it while trying to start the engine. Keep your cool, engines are basically simple, compression, fuel and spark near the top of the compression stroke and it will operate. Last thought, check the fuel line routing to and from the fuel filter, there are manuals out there with the incorrect routing. Search this forum for the correct routing, in fact have a good read of these postings which are brilliant: 'MFI simplification thread' and 'Mechanical fuel injection resource index'