360 LA engine crank no start

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Owen Diaz

Owen Diaz

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I have a freshly rebuilt engine and I’ve been trying to find a reason why it’s not starting tried everything that’s on all the forums about ignition timing and spark and fuel I don’t know what else could be wrong but if I’m missing something please let me know i am kind of a beginner with this so any help or tips will be appreciated also for some reason I have to jump my starter to start it when I try to start it with the key the starter just clicks had a short when I first connected the starter which caused the whole car to lose power fixed that but still have that problem
 
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First make sure that the engine is on TDC, I use 15 degrees before TDC.
then check rotor is pointing to number one spark plug terminal.
If this is correct, is the carb pumping gas? should be able to see it when you pump the linkage, the accelerator pump should squirt
Put a phillips screw driver in to one of the plug wire and have it be touching a ground
crank it over and see if there is a spark from the screw driver to ground, if not then there is something wrong with the wiring, check the start cycle for spark and then the run cycle, mopar has the two cycles of flow of electricity. Use a light probe to check this at the ballast resister terminals.
Good luck
 
hey Owen
welcome aboard

couple of things to consider, does this 360 have a new cam in it?
if it has, you are going to want to do a break in for it, meaning as soon as it fires you get it up to 2000-3000 RPM and keep it there for about half an hour

(that is provided the cam was not properly broken in by your engine builder)

the very first thing i would check it that the engine is not only on the top dead center of the number 1 cylinder, but also that it is on the TDC of the compression stroke

(being a 4 stroke engine, you will run across TDC twice for every time it fires)

next, i would bypass the ballast resistor
it is a little white doohicky mounted on the fire wall with two wires going in, and two wire going out
you can make a quick jumper wire with two spade connectors and bypass it for now
(all it does is lower the voltage to the coil when the key is in the run position)


next, check for fuel
as mentioned, opening the throttle and looking down into the barrel you should be able to see the little squirts of fuel

if you dont, we need to follow that path down



who build your engine?
are all parts compatible with the car your putting it in?
did you reuse the stock distributor?
how old is the gas in the tank?
 
You'll need a voltage meter to check for voltage at the coil and or ballast resistor. Do you know how to jump the starter relay? If you do you can check for spark with key on in run and with spark plug wire almost shorted you can check for spark with you under the hood. If you have a spare spark plug use that to check spark, just ground plug and you'll see spark and if it is strong enough.
 
Compression, fuel and spark.

1..Compression. Are you sure the cam is in correctly? Have you checked compression? And if you have cranked it "a lot" you may not have enough oil on the rings to gain compression

2..Fuel. Fresh fuel. Make SURE it is fresh fuel, squirt a little in the carb throat. Have you checked the plugs? Wet or dry?

3...Spark. Good spark and at the right TIME. "Rig" a test gap, crank it using the key and "rig" this with a solid core coil wire. You should get a nice hot blue spark at least 3/8" long. You can briefely crank it and check timing "on the starter" with a light.
 
Just came to mind, after finding TDC, does the marks line up on the balancer to chain cover mark?
 
Owen Diaz said:
Thank you and I’m not sure if I do have spark at the right time how can i find that out
Click to expand...

go back to the number 1 cylinder and make sure it is at TDC on the compression stroke
then pop the top of the distributor and make sure the rotor is pointing at the #1 cylinder post
then follow the plug wire on that post and see if it is connected to the #1 plug

that should get you close
 
Steven190 said:
First make sure that the engine is on TDC, I use 15 degrees before TDC.
then check rotor is pointing to number one spark plug terminal.
If this is correct, is the carb pumping gas? should be able to see it when you pump the linkage, the accelerator pump should squirt
Put a phillips screw driver in to one of the plug wire and have it be touching a ground
crank it over and see if there is a spark from the screw driver to ground, if not then there is something wrong with the wiring, check the start cycle for spark and then the run cycle, mopar has the two cycles of flow of electricity. Use a light probe to check this at the ballast resister terminals.
Good luck
Click to expand...
I pulled the plugs and it does have spark and the carb does squirt gas the only thing I haven’t checked is the ballast resistor
I’ve done tried at 0 degrees and at 10 before TDC I’ve also gotten back tires from cylinder 6 and 8 when I started spinning the distributor while starting it to see if I can hear it trying to start but still don’t get anything
 
Have you followed above suggestions?
Lots of good advice(smarter than me). It might help if we saw pics of your setup?
Quite often if engine cranks but doesnt start, it is due to blown ballast resistor.
Also verify firing order 18436572.
Owen Diaz said:
It does crank
Click to expand...
 
Owen Diaz said:
I pulled the plugs and it does have spark and the carb does squirt gas the only thing I haven’t checked is the ballast resistor
I’ve done tried at 0 degrees and at 10 before TDC I’ve also gotten back tires from cylinder 6 and 8 when I started spinning the distributor while starting it to see if I can hear it trying to start but still don’t get anything
Click to expand...

Don't worry about the ballast resistor if you have spark. If it is backfiring out the carb you may have the dist 1/2 turn (180 degrees off). HOW DO YOU KNOW you are on the no1 compression stroke? HINT!!!!!: The timing marks don't tell you this!!!!

Have you checked compression/ leak down?
 
take Number 1 plug out, hold finger on hole, crank, when pressure blows out you are on compression stroke, rotate crank over, if you can by hand, to TDC.
 
Update: just did a compression test only did cylinder 1,3, and 5 and the first one was at 60 which is real low considering it was at 180 psi the next two were berally over zero what should my next step be?
 
A leakdown tester. You can buy them, or look up plans on the 'net and make one with some pipe fittings and a few pressure gauges.

It should still run with one or two dead cylinders. Maybe test the other 5 first.
 
Was compression test done with carb opened all the way? Something I never knew until recently.
May as well all the cylinders to get a good baseline on all them.
Owen Diaz said:
Update: just did a compression test only did cylinder 1,3, and 5 and the first one was at 60 which is real low considering it was at 180 psi the next two were berally over zero what should my next step be?
Click to expand...
 
4spdragtop said:
Was compression test done with carb opened all the way? Something I never knew until recently.
May as well all the cylinders to get a good baseline on all them.
Click to expand...
No it wasn’t and yea I will do it on all of them just didn’t want to get caught out in the rain
 
found out that my timing on the timing chain was a whole 180 off don’t remember putting it in like that but yea and I also think when my cylinder heads were resurfaced they were shaved too much I’m not sure which of these resulted into me bending a valve​
 
is it possible for mechanic timing to be 180 off? or only ignition timing can be 180 off?
Also would anyone know why only the smaller valves hit the cylinder head?

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