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Engine won't fire up with Sniper
#1
So after weeks waiting got my fuel hoses and starter broke the moment I wanted start the sniper for first time. (what were the odds)
Now got the new starter in place, time to try: tadaaaa.... nothing Sad

The starter --> wow. way better than the previous hi-torque mac leod. Engine kranks like a modern car!

but now engine won't start with the sniper... 
The handheld device gives me all sensors, all within range.
Got a non ECU controlled setup. (so yellow wire at neg pole of the bobine)
Got fuel going in (and back as well, I can hear it flush back in tank when I stop cranking)
Got RPM's tach signal, seen by handheld while cranking.
During crank, once every few rotations, the engine makes one or two attempts, but not enough to really fire up.

Then measured the current at (pink wire of unit)
supposed to be a 12v during crank and while key on. I saw it drops to 10 something.
I've seen few reports of the unit failing if not 11+.

I'm currently using a splice of the green/red wire, right after the ignition switch.
So question is, if its not this wire, which one would give me 12V key-on and during cranking?

73 modified Grandé 351C. Almost done. 
71 429CJ. In progress
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#2
Be aware dont crank to many times or engine will be flooded


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#3
I used the same wire as the msd box at crank should be Pink

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#4
Is the battery charged ? You could run Another wire directly to sniper unit just to check if it starts.
Which distrbuitor are you using ? Try to disconnect the battery for a few seconds and try again, does the handheld flash when you crank the Engine ?
Do you have the air filter on ?

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#5
Rob,
its the pink wire of the unit, spliced on column after the switch using the reg green wire
-->Q: there are actually two, one supposed to go to starter solenoid, one to coil.
they have same color. Could there be a diff here?
-->Q2: you have 12v during cranking on this wire?
-->Q3: how could I make a new source, as we need go thru the ignition switch?

[Is the battery charged ? ]
Battery is new, fully charged, and KO test shows steady 12V+ on device.
In between trying, I let the battery be recharged. The new starter turns the engine with zero effort, like if it was a Fiat 500 engine Smile
Using a mallory distributor, and the handheld device gets a tach signal.

[does the handheld flash when you crank the Engine]
no stays on, no sign of juice shortage. while its just above 10v as voltmeter shows.

[Be aware dont crank to many times or engine will be flooded]
I've checked plugs and there were dry. Even after "long" crank. Which will bring me to next test: poor some fuel by hand and try right after
if I get some start. On a carb situation where engine would behave like this during crank, i'd have pumped a few times.
--> Q4: In wizard set camshaft choice as the default, stock/mild. Mine is a 278, is it more street/trip and could it make a difference?

73 modified Grandé 351C. Almost done. 
71 429CJ. In progress
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#6
Ive not hooked it up like , because I have the msd box. I only used a wire from the ignition switch the same that goes to coil.
Do you hear the fuel pump ? Connections correct on inlet/outlet on the sniper efi fuel lines ? The plugs should not be dry, because it squirts an amount on every crank. Mine is 280 and I use street/strip
Try to disconnect battery and redo wizard

Regards Rob

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#7
[Do you hear the fuel pump]
Yup, when I turn key, I hear it, stops after few secs as specified.

[ Connections correct on inlet/outlet on the sniper efi fuel lines ?]
Yup, checked 200 times.

[The plugs should not be dry, because it squirts an amount on every crank.]
Yeah and that's what the engine feels too, on carb, if it would "almost", i'd pump to help it
Tried pour 1/2 small glass fuel, no change tho.
Tomorrow, I'll try disconnect and put into jerrycan the main feed to see if it really delivers as expected
or if it's somehow restricted.

Also while checking everything, I saw fuel lines side from back wheel to front that were placed with some bits of tension
hold every 30cm, to stay nicely under car floor, were now hanging like xmas decoration. On the +- 2 meter, I have now something like
8 cm extra vs during instal if i put them back under tension on the whole length. Looks these Vapor Guards hoses supposed to handle all modern fuels have reacted to fuel..
Will prolly replace these by hard line, but will do this later after that damn thing does something.

73 modified Grandé 351C. Almost done. 
71 429CJ. In progress
  Reply
#8
If you detach the fuel line that goes Into the sniper and put it Into a can you can check pressure. Check the settings for pressure in the handheld.

Regards Rob

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#9
Double check that the red and black wires are correctly connected to the battery and that the fuse is good.

The red-light green stripe wire, at the ignition switch before it connects to the resistor wire, is the feed wire for the coil when the ignition key is in either run or start. The light green-red stripe wire provides reference voltage to the voltage regulator and excitor voltage to the alternator I believe only when the key is in run, not during cranking.

It is normal for the battery voltage to drop a couple of volts when cranking. Because you have been cranking without the alternator charging it I would connect a battery charger to make sure the voltage to Sniper doesn't get too low for it to function.



“If you can't explain it simply, you don't understand it well enough.”
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#10
Don & Rob (thx for the reply guys, appreciate the help atm...),

Don,
Battery is new, battery cables are not corroded and sniper b and r wires are on both poles. triple checked them.
The display gets its power from this source just like the unit. So a blown fuse in unit harness would not allow the sensors to be ok on display if display would light up at all.
On key on, the unit boots ok and is ready after 2.5 secs. The fuel pomp also turned during that time.
battery power is on unit during cranking and displays 12.3 volts. Will try find out where is the fuse in this new harness and check it.

[It is normal for the battery voltage to drop a couple of volts when cranking.]
Yes but so far I could dig some infos on fora's, the lack of having 12v is often given, as some have much bigger drops causing the handheld and unit to fail.
And this drop is now seen like some basic install mistake, for bad wiring or wrong sources, its very hard to tell is related to what I see or not.

[I believe only when the key is in run, not during cranking.]
The pink wire is 10+ volts during cranking, so I guess I have the right one. Tho will do again some gym tomorrow to test the other to see if its hot while cranking and compair its voltage.
Would it stay on and drop less during cranking, I'll swap the source.

[ I would connect a battery charger to make sure the voltage to Sniper doesn't get too low for it to function.]
I guess i can do this, tho up till now, I was disconnecting the charger in between tests. The new starter turns with great ease and doesn't drain the battery as the old hi-torque would have done quickly.
The battery is also high amps, something like 80+, so it can handle.

Rob,
[If you detach the fuel line that goes Into the sniper and put it Into a can you can check pressure.]
Yeah I will, tho how do I measure pressure? I have a fuel pressure sensor for injection, that I used for my t-bird 5.0, but don't think I can connect it easy...
so could you extend on the way to check the pressure with the handheld device?
For now, I saw it gave me a 60 psi after pump load of turn key.

I will also clean up/inspect all plugs, vs only cyl 1, the easy accessible one Smile , as I recall I have dual plane, and may be some other are flooded

As its nite over here, I will continue in the morning (if my wife doesn't get some todo idea Smile )
Meanwhile, any ideas, things to checks --> shoot!

73 modified Grandé 351C. Almost done. 
71 429CJ. In progress
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