new engine start-up problems
 

Hello fellow V8ers. Today I went to fire up a fresh 59ab with a Bubba's crab ignition and 3 97s rebuilt by Max in SLC. Once choked she fired up, but slowly seemed to "load up", eventually dying. From then on out it would do little more than cough. One of the symptoms was a periodic blue-flame backfire out the exhaust, and the electronic tach was jumping around bad.
Before I mess with Bubba's ignition, I'm wondering if maybe I have low voltage to the coil? Or.....? Any help would be appreciated.

Re: new engine start-up problems
 

Are you running progressive linkage on the carbs? If so are the outer carbs set up as secondary carbs? It sounds like it might be over loading up with fuel. With progressive linkage the two outer carbs should not be operating at idle. Try disconnecting the linkage and check that your outer carbs are not part operating. A quick test is to put your hand over the intake of the outer carbs to see if the are sucking any air. The engine should run fine on one carb and then you can add the secondary carbs once you get it running right. Hope this helps.


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Re: new engine start-up problems
 

Agree sounds like too much fuel ! Eliminate the outer carbs from the break in procedure before you wash out the rings . Change manifold if possible or completely block off carbs .
More info needed , volts to coil , type of coil , still 6 volt or changed to 12 .
What kind of tach ? What fuel pump ? Still using a resistor?

Re: new engine start-up problems
 

Have you tried pushing in the choke most of the way once it starts with a little throttle?

Re: new engine start-up problems
 

Beside above suggestion from Bursonaw check the ignition wiring to the coil and ignition switch.

Re: new engine start-up problems
 

Good questions all. Here is some more info...
Yes running progressive linkage. The outer two should not be coming on at all at this point.
Outer two chokes are locked out, however I did try working the center choke. It needed that to fire initially, but then it stopped making much of a difference when it wouldn't run anymore.
It's a Skip Haney coil, converted to 12v. I'll get the numbers on voltage to the coil when I get back out there late this afternoon (work calls!).
Mechanical fuel pump with a regulator on it set to 2.5 lbs.
Modern Stewart Warner tach.
When we were trouble shooting some other issues previous to this we bypassed the resistor temporarily. Haven't plumbed it back in yet, but I wouldn't think that is the issue(??).
Appreciate all the advice!

Re: new engine start-up problems
 

Are you sure Skips coil requires a ballast resistor? As already stated, I would remove the two outer carbs and block off the manifold. That way you are eliminating two possible sources of the issue. They serve no purpose at this point and increase the difficulty of trouble shooting.

Also might want to put a pressure gauge on the fuel line and double check that the regulator is working correctly.

You could also pull the spark plugs and do a compression test on the cylinders and check the plugs over.

Re: new engine start-up problems
 

I always use a known good stock carb and manifold on the initial start of any engine I build, regardless of other modifications. It's easy on a flathead because you don't have to drain the cooling system to change it later (obviously).

Re: new engine start-up problems
 

The use of a good, stock manifold is a great one. Trying to figure out how I can block off the two outer carbs with my stainless fuel line set-up. I have a small fortune into it, finally getting it to stop leaking at every fitting (last time I use stainless), so to mess with it doesn't sound appealing.
Those junk pressure regulators are just that. But unless Charlie Price can figure out a way to reproduce those cool looking Edmunds regulators and get them to work with modern gas, not sure there is another option.
A lot of you guys are angling at the fuel. I'll focus in on that when I go back out there today after work.

Re: new engine start-up problems
 

Don't worry about the fuel lines yet. Block the top of the other two carbs off with couple of pieces of wood or metal. You may be thinning the choke effect with the other two carbs open.

Re: new engine start-up problems
 

The idle circuits are still in play with the outer carbs , meaning more gas , and that’s assuming the power valve isnt leaking . Block off the outer carbs , thin alum under the carb or remove and use what ever is easiest . Running good witout ruining the rings is priority, looks are secondary .

Re: new engine start-up problems
 

I am also just about to fire off the newly re-built 59L, but am using a stock manifold, a known 94 carb that Charlie NY rebuilt, along with a 21A dist he did also. I don't want any extra issues to deal with until it is sorted out. Then I will install the Offy manifold and WCFB that Charlie also modified for me. The last thing I need after all this work is excess gas washing the lubrication off the cylinder walls and diluting the break in oil.

Re: new engine start-up problems
 

I always do what Tubman and russcc do. As noted, you don't want to be washing down the cylinders. Break the engine in with a known good carb and distributor. Then work out your 3 X 2 setup and distributor.

Re: new engine start-up problems
 

You don't have to totally disassemble the carbs and fuel lines if you would prefer not to. Loosen up the carb mount bolts and slip a thin blocking plate between the carb base and the manifold. May take a little messing with this solid gasket to get it to fit, but shouldn't be overly difficult.

Another question, you are not attempting to use stainless steel lines between a firewall mounted fuel block and the carbs are you? Or are all of the fuel lines on the engine itself?

Re: new engine start-up problems
 

Skips 12v coils DO require a ballast resistor.

Re: new engine start-up problems
 

Then guess it's not a 12v coil is it. :) That's why I ask the question, you really need to know what is needed before trying to use it. IMO it is always better to use a coil ballast resistor combination, but a lot of people like the simplicity for the coil only.

Re: new engine start-up problems
 

OK here is the latest:
-Unplugged the outer carbs and then covered their inlet with tape.
-Checked voltage at the coil and it's got 9 volts.
-Tried to fire again but it acted exactly the same.
-Cut the pressure regulator to it's lowest setting (.5 lbs) and even drained the bowls of the outside carbs.
-Just like last night, it goes from firing and sputtering for 10 secs to nothing on about a half dozen attempts.
-Plugs look wet, but not sure that tells me anything since it's pumping fuel but not firing - of course they're wet.

And no I am not running stainless from the firewall to the carbs. I bought one of Charlie Price's stainless lines that comes from the mechanical fuel pump (with the regulator in between).

So, gents, what say ye? I'm lost.

Re: new engine start-up problems
 

Each time you try something to fix are you cleaning plugs? If plugs are fouled or wet you will never diagnose your problems.

Re: new engine start-up problems
 

I would think the wet plugs would be a clue. They will not fire if wet.

Re: new engine start-up problems
 

If there’s no spark or ignition is not functioning correctly they will be wet.