Hi Snapped

Primer pump - yes the copper sealing ring and tiny o-ring are replaced.

Just thinking out loud: if the lift pump is under-performing, would there still be white smoke (=unburnt fuel) generated as the engine tries to run?

I will have to follow all leads.

Cheers

White smoke makes the timing of the injection pump at least suspect. You also might have two problems. From your description I would verify the fuel is being pumped properly first.

Got overflow from the relief valve on the injection pump when cranking? If not find out why not. When you pump the primer pump with the engine off is there a reasonable stiff resistance or not developed? Say there is no resistance as an example. The check valves for the primer pump are in the lift pump. Or the relief valve can be open. Or you could be piggybacking on the lift pump with the primer pump as the lift pump alone cannot pull fuel through say a bad tank filter otherwise. In other words diagnose what is wrong in the fuel supply system if anything first.

It sounds like you are basically just shot gunning or changing things with no primary diagnosis. This can get very expensive and mentally pain full. At least these cars are service friendly compared to what I ran into yesterday.

I looked at what was a simple brake line failure on my beater.. The young fellow helping me had a jack slip. Took out two lines to and near the equalizer. I told him if we could not access the nuts and get them out. Cut all the six lines and we will mount the equalizer in a higher workable position. I called the car brands dealer. .Six to eight hours labor quoted if things went well. So we should be happy that in general there are only one or two areas in these old 123 types. Plus the earlier 603 engined cars that may cause some real unreasonable difficulties when working on them.

When you pump the primer pump with the engine off is there a reasonable stiff resistance or not
The hand primer pump feels as it should, and after a couple of pumps I can hear the fuel going through the bypass valve. This is the original bypass valve.

Start with the easy stuff first, e.g. put a clear pvc line in place of the cigar hose to eliminate air in fue
When you ran the car using a temporary fuel can in the engine bay, what was the discharge rate of the fuel going into the can?
I will check these tomorrow, cheers.

The injectors were professionally rebuilt with Monark tips, I even took them back to be rechecked - I am assuming they are not leaking. Will post back.

But was the injection pump timed on the right stroke in the posters case? I figured no n/a engines had the easy to use timing port and tang. Type injection pump. Maybe the very last European versions did but I do not know.


When installed on the wrong stroke the injection pump will time in beautiful. Other than it is wrong. You have to see those first cylinders valve lobes. pointing generally upward. Other wise it is only a fifty fifty chance you have it right. After major engine work especially.

I would personally verify the fuel supply to the base of the injection pump is good. As this should be the quickest and easiest. It is even possible he has two problems.

Also I forgot this was a conversion. If there a chance the engine is starting pretty much normally and then just shutting down as the vaccum develops?


How did you set up the shutdown? Simple test is to remove the vacuum line from the injection pump shutoff. Although I have no ideal of how pumping the primer pump could overcome that valve if it was shutting off. Also I would not expect all the white smoke.

If the white smoke is un-burnt fuel, i.e. it smells like fuel and not coolant, then it's air in fuel or injection timing, or poor atomization of the fuel and or peeing injectors.

Start with the easy stuff first, e.g. put a clear pvc line in place of the cigar hose to eliminate air in fuel rather than r&r re-time the injection pump or pull and pop test the injectors. Of course you can do the hard stuff first (I see this over and over again) and have it snow ball into a bigger and bigger job.

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