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Hi everyone,

Looking for some thoughts on my worsening issue in regard to starting problems on my engine.

So the issue, which started about 4 months ago, is that when starting from cold after leaving for a period of time, the engine has problems starting and won't go to high idle on the electric choke (engages the choke cam though). When it does fire, it sometimes has white smoke from the left bank. If you stop the engine, remove the plugs they are wet (but not oil or water). After cleaning the plugs, refitting the engine may fire up but has a rough idle for about 2 minutes if you keep your foot on the pedal and then will sit at 800 rpm steady and you can open the throttle (from the throttle linkage or accelerator and it sounds great). If you switch off and leave for a few minutes it will start and be OK. If you switch off and start again in about 20 minutes it has a hard time starting.

As the issue got worse, it suffered blowback through the carb accompanied by a flame.

Now for the things I have done. The original 770 street avenger started leaking raw fuel out of the secondary spindle shaft and pooled on the inlet manifold (not good). I spoke with Larry Stock and purchased a new Quickfuel (Holley 650 double pumper based carb with mechanical secondaries) and fitted it this month and still have the same problem…

I have just completed a compression test and all cylinders rate at 168 to 170 PSI cold. I have also spun the engine up with white towels by each plug hole and 'nothing' came out, bar the smell of fuel.

It has new MSD leads, new Autolite 25 plugs fitted and had a new MSD pro-billet 8350 all in one distributor fitted just over a year ago and was fine until about 4 or 5 months ago.

I am hearing the MSD can be unreliable and may suffer if you have had any welding done (I did to put the original seat belt mountings in). Does anyone know if this is the case? I am also hearing I should have fitted a Duraspark based system, again any views?

So I am looking for ideas why the starting is difficult, why there is sometimes white smoke and why on the left bank. Also what is the usual cause of firing back through the carb?

Look forward to some assistance with this one!

Regards

Adrian
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quote:
The original 770 street avenger started leaking raw fuel out of the secondary spindle shaft and pooled on the inlet manifold (not good). I spoke with Larry Stock and purchased a new Quickfuel (Holley 650 double pumper based carb with mechanical secondaries) and fitted it this month and still have the same problem…

Still have what same problem? Fuel spilling out of the secondary spindle shaft and pooling on the intake manifold? Or the hard starting?

And how old is your harmonic balancer? Is it the original? Sounds like the outer ring could have slipped.
To answer your original post, YES- electric welding of any kind for any length or time on a car is very bad for any connected electronic devices. This definitely includes MSDs as well as Ford TFI boxes and anything similar. While electronic ignitions and EFI controllers usually fail entirely, occasionally the damage is such that they continue to sort-of work for a while. I would at the very least send the box back to MSD and ask that it be tested.
Thanks Guys,

yes, the timing is my next check. The engine has a 7 year old fluidamper set up fitted and also still has the 'electromotive' distributor less timing wheel fitted (before the system was returned back to normal distributor/coil ignition - see picture). I have not checked it and so will see if there has been a slip. As Larry said, if its not a fuel problem, its ignition!

I will assume static start at 15 degrees and go from there. I also have the opportunity to borrow/substitute a distributor this week so again will help eliminate the problem hopefully. After all, I don't want to screw up Larry's new carb as when it is running the throttle response is great!

Thanks again..and I will indeed send the 14 month old MSD back to MSD and see what they say.

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quote:
Originally posted by LF - TP 2511:
quote:
new MSD pro-billet 8350 all in one distributor fitted just over a year ago

Haven't previous owners had failures of "new" distributors due to weak factory gear pins?

Backfires are 'usually' engine timing related.

Larry


Yup. I believe that a similar situation was discussed in a previous thread and the end result was that the gear pin had bent.

The end result was that MSD upgraded their design to include a better drive pin.


Apparently the call of any MSD product is just overwhelming and irresistable.

To me it is just the call of the "Siren" calling "sailors" to their demise?

This stuff is just constant with MSD products.

Might Suddenly Fail I guess is just not a consideration at all? Must be the contingency money MSD pays?


I just asked Jon Haas about the "welding issue" and he said it does not exist with his. He referred to it as a "wives tale".
quote:
welding issue" and he said it does not exist with his. He referred to it as a "wives tale".


Maybe Jon's wife does a lot of welding on Panteras with MSD products installed. It is an "old wives tale" that wives weld Panteras without taking proper precautions to protect the electronics. My wife would never do that.

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