hard engine starting

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ap6street

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sometimes my motor takes a few cranks to fire.
it shows no sign to want to fire , then maybe 3rd or 4th time she fires right up and after 30 seconds of 2000rpm it idles great.

410sbc
266/272 110 solid roller
locked timing 28
msd 6al / pro billet dissy
950 carb
12:1 comp

i am concerend about how this affects cylinder bores / washing down the oil.
also fouling plugs .. etc etc

near new motor
at cranking i have 10.6Volts
 
ap6street said:
sometimes my motor takes a few cranks to fire.
it shows no sign to want to fire , then maybe 3rd or 4th time she fires right up and after 30 seconds of 2000rpm it idles great.

410sbc
266/272 110 solid roller
locked timing 28
msd 6al / pro billet dissy
950 carb
12:1 comp

i am concerend about how this affects cylinder bores / washing down the oil.
also fouling plugs .. etc etc

near new motor
at cranking i have 10.6Volts
Click to expand...

Sounds like you figured it out.
 
so wont cause any damage with hard starts pumping a bit of excess fuel in ??
i know few people with similr motors that seem to start so much easier
 
ap6street said:
so wont cause any damage with hard starts pumping a bit of excess fuel in ??
i know few people with similr motors that seem to start so much easier
Click to expand...

Cranking voltage WAY too low! Keep that battery on a tender. Check your grounds. If voltage is too low, it will take a TON of fuel to light off.
 
well how hard should a motor like that take to start , once warms its fine.
and cold start im talking ambient temp of 70.
msd 6al ??
 
It could be something as simple as a choke adjustment.
If its not running a choke, then it takes a few shots to fire.
 
The "locked" distributor? To high initial timing for easy (soft-lol) starting?
 
I hope those cam numbers are at .050" lift! Things of notice:
- a lot of timing at start up
- 12:1 scr (but the actual cam numbers need to be known)

When you say you crank it over 3-4 times: in the first few tries, does the motor spin quickly or is it wanting to stop dead or kick back on the starter?

10.6 is not bad for cranking voltage but what is actually at the starter is key. OP, is this measured with your meter leads across the battery + and -, or measured across the starter terminal and starter case?
 
10.6V IS JUST FINE

TEN POINT SIX VOLTS IS JUST FINE!!

Back to basics..........Start with checking "cranking" spark. Check spark while cranking USING THE KEY This is important because it sets up the exact conditions during "trying to start."

Get yourself a spark gap checker or make one. "Rig" it up at the coil using a SOLID core plug wire NOT the resistor wire. What you want to do is check the coil output without ANY of the "in use" components on the engine, IE coil wire, cap, plug wires........you want them all out of this test.

With MSD obviously it should have an IMPRESSIVE spark

Try it a few times to make sure the ignition switch does not have an intermittent.

Next test you want to begin BEFORE you have run the car, start cold in the morning WITHOUT cranking. Open the hood, look down the carb, and work the throttle looking for accellerator pump spray. If not the carb is boiling dry during parking.

Also, before cranking, pull the plugs and examine them for fuel fouling. What you are "wondering" is "if" the carb is boiliing over during park, and running fuel down into the cylinders with open intake valves.
 
You need to supply more details. Does carb have a choke? Is it running a mechanical fuel pump or electric fuel pump? What is your cold start procedure, step by step?
As others have mentioned, this could be normal for your current combination.
 
Starter is good and cranks motor very quick.
Battery In boot. 10.6 volts is measured at the msd +&- under the dash.
67dart273 sorry I don't follow that spark test.
Electric fuel pump, return system.
My startup procedure I turn on fuel pump top up bowls. Then crank the engine and give it a small pump. It does shoot fuel.
Pink cam/33nozzles.
Normally no sign from engine.
I will only let it crank over for maybe 3 seconds.
Will need to do this at least 3 times, same procedure until when the engine fires and it usually fires right up.
 
10.6 v is in the spec range for startup for the MSD so that seems OK. And starter circuit seems fine since speed is good. So it sounds like fule/air mix or spark is not right.

What 67dart273 is saying is to first check spark right out of the MSD coil wire first to make sure it is good from the coil. I would disconnect the wire from the coil from the distributor and set the distributor end of that wire about 3/8" from metal. Crank for a second and watch to see if a hot blue spark comes out the first crank when cold. Then reconnect that wire to the distributor, pull a plug wire from its plug, and put the open end 3/8" from metal and again crank, looking for a hot blue spark. If good both times, then you know spark is good and the fuel is the issue.

If the spark is good, I would pour about 1/2 teaspoon of fuel direct down the carb and crank. If things are right in the spark, then it will fire almost immediately and run on that small gob of fuel for a second or so.
As above, any choke in the carb?

What temperature is it there now?
 
i could also add that although same engine with a slightly smaller cam.
the engine much preferd the startup from a slower cranking starter .
this ones cranks much faster yet doesnt fire.
this ones a cvr protorque 3.1hp
 
50* here now

bit early in the morning but i will be trialling this in 30minutes.

ok i will trial both spark ideas.
should i try every plug ???

fuel shouldnt be an issue , because i can see the squirters giving a fair shot down the carb.

not sure if it matters.

running no air cleaner on the carb, although i have tried chucking one on at startup but no difference
 
How do you know it doesnt want more fuel to light off?

I you drive it, shut it off, come back 30 min later and just turn the key....if it lights on its own eventually then that is what you mention. ..but if it doesn't light till you pump the peddle....then just pump the peddle before firing it next time.

Am I missing something?
 
it will fire without anything or maybe a slight touch of throttle 30min or even an hour or 2 later .
just after a week or 2 . very hard to fire .

im just worried about washing the cylinder bores

as for spark both coil and plugs wires had a great spark so no trouble there
 
The fuel is evaporating.

You're gonna have to crank it to get the bowls filled.

Pump the peddle a few times and crank, but the fuel takes a sec to get to the carb.

You're fine.
 
67Dart273 said:
...Open the hood, look down the carb, and work the throttle looking for accellerator pump spray. If not the carb is boiling dry during parking.
Click to expand...
Thats my guess. An electric pump will remedy that. I had a carter electric pump on a stockish 340 with an AFB. That pump would go crazy for about 10 seconds every morning as it would always boil the fuel out overnight. My distributor advance plate was sticking also.
 
ap6street said:
Starter is good and cranks motor very quick.
Battery In boot. 10.6 volts is measured at the msd +&- under the dash.
67dart273 sorry I don't follow that spark test.
Click to expand...

What you need to do is try and determine if it ACTUALLY has spark right out of the coil, EVERY time, when you crank the engine using the KEY (In other words NOT jumpering the starter relay)

Get a test gap like this:

This one is nice because you can adjust it

Lisle® 50850 Ignition Spark Tester

l50850__57428.1406568988.jpg


Hook the clip to a ground. Rig a SOLID CORE wire between the coil tower and the tester. Since you have an MSD, I'd open that gap way up to 1/2" or so. Now crank the engine using the key. You should have LOTS of nice big fat spark

Try it 'a few times' to make sure you don't have in intermittent in the ignition switch.
 
ap6street said:
has an electric fuel pump , so i will fill the bowls before i try crank it
Click to expand...
ok, disregard.....Check your advance plate? Just a shot of lube. mine was obviously gummed up upon inspection.
 
i have no problems with the effort starting the car , its just if its causing damage and ive noticed most dont seem to have any dramas
 
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