First Start Up

QueensEng · QueensEng's Garage

Hello fellow Pelicans,

so after a long summer of rebuilding the top end of my 82 SC, the engine is in, the oil is in, the fuel is topped up and the exhaust is backdated. The problem I'm having is that I recall before I took it apart when I turned the key to on I'd hear the fuel pump working for 5 seconds or so then turn off but now when the key is on it doesn't stop... ever. Foolishly I figured it was working fine and that it was my memory that failed me but then when I spun the engine to build oil pressure then started it, it fired but blew more white smoke than you could possibly imagine, so I opted to pass on the 20 minutes of break in which I hope isn't to my detriment but I figured there's something wrong and I'd have done more damage than good. So what are the theories out there? Has this happened to anyone else, possible trouble shooting instructions? I'm going to pull a spark plug tomorrow and have a look, that should give me a good idea of what's happening in there.

beepbeep · 10-03-2009, 01:45 AM

Fuek pump should shut off when the key is off. I believe there is a switch on the top of CIS flapper which acts as a fuel cut-off (maybe it's other way around on SC, as 930 has CIS other way around). Regarding smoking, did the smoke dispersed after a while or did it just kept on smoking for whole 20 minutes?

It's normal for engine to smoke after rebuild. If it sounds OK, doesn't leak oil, has full oil pressure, runs well and smoke is gradually disappearing then I would just run it on a short trip to burn off the oil residues in exhaust.

What did you rebuild? Were valve guides in good shape?

prschmn · 10-03-2009, 05:37 AM

Something holding the trap door open or plug to switch not connected?
Can you hear the nozzles squirting when its running?
If you drown the cylinders with fuel your rings won't be happy.

QueensEng · QueensEng's Garage

I didn't run for the whole 20 minutes because it just didn't sound/look right. The smoke was thick and abundant. I'm pretty sure I was drowning the cylinders because I started the break in with a half tank and after about 20 minutes of the key being on and hearing the fuel pump pumping, regardless of whether the engine was running or not, I ate through a quarter tank of fuel.

QueensEng · QueensEng's Garage

Here's an idea... could it by chance be my fuel accumulator? I've searched this forum HIGH AND LOW, and the best I could find was Aurel having trouble with a faulty fuel pump NOT delivering fuel to his injectors at all, which mine does... Puh-lease indulge me with some knowledge?

prschmn · 10-05-2009, 03:46 PM

The accumulator just dampens pulsations. Not the cause here.
Are the two connectors plugged in correctly? The trap door/fuel pump relay and the cold start valve are close in color. If they are reversed the fule pump will run as soon as the key is on. Regardless the nozzles should not be delivering fuel
until the trap door opens a bit.

Flat6pac · 10-05-2009, 07:00 PM

Around the front of the engine is 2 connectors 1 on the back of the airflow sensor and the other is the 7th injector for cold start. If they get mixed up you have the pump running without the cold start working. You need to ohm from the wire on the chain cover to the connectors in the front. The one that will ohm is the cold start 7th injector
If youre running too rich the plate is hanging up giving you too much fuel
If your accumulator is bad, its a diaphram, the SC runs the leakage around to the return line to the fuel tank. This could be a pressure problem so the pin in the fuel distributor isnt returning to the bottom idle rest.
just some thoughts
Bruce

QueensEng · QueensEng's Garage

It was the fuel pump not delivering enough pressure, it's been fixed, old Bessy fires RIGHT up, clean and smooth with a wicked sound out the new Billy Boat exhaust. Thank you all for your help I could not have done this rebuild with out these threads.