Thread: Motor With no Spark/ Horse Power Question

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I havent be able to get any help from anyother forum I was sort of hoping I could get some help here!

My Dad just got a motor for his 84 GMC 4x4 he got it from an 85-86 Chevy Impala. I was wondering How I could get it to fire? sort of a dumb question I know But I've tryed everything new plugs wires cap distributor timing is dead on I checked all the fuses I dont under stand Unless I have a dead Coil, its brand new though. Anyways Its a 350 or a 305 Im not sure what it is its one of the two. How could I Build Horse Power without taking the motor to a machine shop to have it bored and stroked... port and polished. My dad was hoping for a motor that would run nice and have a little kick when he came on to the throttle... It has quad track rearends and its sort of gutlass... Well the last one that he had in it was. I was sort of hoping I could get it running for him and have a bit of horses for him by fathers day but that wont happen. But it can be a belated fathers day gift. If I could get any help from anyone it would be greatly appreciated

Thank you

Ed

Hey Ed,

No question is dumb...we all find ourselves needing some assistance when we've exhuasted everything we can think of.

So, is the problem that it just won't start or that you're not getting any spark? Let's assume that you mean you've got no spark. There's only one thing to consider...the ignition system (i.e.: distributor and coil). Since this is out of a late model vehicle, it's probably HEI. In any case, have you tried to pull a spark plug, connect the plug wire, and set the spark plug on the engine to see if you get any spark when you crank it? If you are not getting spark, you're choices are:

1.) No power to the distributor
2.) Bad HEI module (not triggering the spark to the coil)
3.) Bad coil

Fortunately, on HEI, there is only one power wire. If you suspect a bad connection or blown fuse, hot wire the "BAT" or "PWR" connection on the distributor directly to your battery. If you then get spark, you know it's a bad wire going to the distributor. If still no spark, borrow your neighbors distributor out of their chevy (optional if you want to tell them or not )and try again.

If you are getting spark, it's a different story...post again and we can try to help.

tj

whats an HEI im not very good at the whole wiring thing! and when i do direct power do i take a wire from the positive post to the Pink wire in the cap? if i recall the 85 had a red looked like external fuses on the drivers side fender wall an a whole bunch of wires ran to it. I just asked my dad about the spark there was some there but it wasnt very good or big enough to ignite the fuel. What could that be?

whats an HEI

High-Energy Ignition. Basically another term for electronic ignition that replaced the old points type distributors. If your distributor has a big black cap and the coil is inside that cap, you've got an HEI.


Well, if you have spark (whether weak or not), then you can rule out the ignition. Again, a weak spark is a subjective term, so unless you have a way to say it won't spark under combustion, but you do see a spark on the plug when it's out, you have to assume it is firing okay. Sounds like a different problem.

Next steps:

Are you getting any (or possibly too much) fuel into the cylinders. Take a plug out after cranking (do this very quickly as fuel evaporates quickly). Is it reaaaaaaly wet? If so, it's flooded. If you see no fuel, try pumping the throttle a bunch of times to squirt fuel into the intake. Did you see a stream of gas when you looked down the carb? Did it start? No? Check the plug again real quick. It should now be wet. If not, you're not getting fuel to the cylinders. Try pouring a LITTLE gas (like about 1/8 cup) of gas down the carb or use a touch of either to see if you hear it try to fire. If it does, your problem is in the fuel delivery. If not, you've got ignition or other problems.

If you are getting fuel but still not firing, check the following:

Is the distributor 180 degrees out? Remember, the cam (thus the distributor) moves at half the speed of the crankshaft. In otherwords, if you're checking the timing mark on the crank to set your distributor, you also have to make sure you are checking the valves are not on the intake stroke. The crank will rotate two times past the mark for the combustion stroke. Make sure the distributor is set about 25-35 degrees BEFORE TDC.

Another option is you have jumped a tooth on the timing gear or the chain or gear is slipping thus not allowing your cam to move. If this were the case, you'd probably have a completely different issue (you'd be banging the valves against the piston).

Was this engine running when you pulled it out of the other vehicle?

my distributor is the same as the red one and its getting lots of fuel i had to disconnect the fuel line so I wouldnt have to drain the cylinders again the timing is 33 degrees and yes the motor was running b4 we took it out of the car i made sure of that because i wouldnt see a point in changing the motor if it didnt run ive done everything imaginable but i cant figure out the problem im sort of getting sick of it.

yes ive done everything! I didn't remove the dizzy and yes its pointing at #1 piston on the comp stroke the only thing i havent tryed was wiring the dizzy to the pos post on the batery i may just sell the motor or trade it for a different one.

i may even need a new wiring harness ive got one here but its fuel injected. Im not sure what to do thats why ive came here for help

Well, if you have "decent" (subjective term there) spark and fuel (that's not contaminated), the only thing left is compression. Do a compression check on the engine and see what the numbers come out at. If you are just trying to get it running but compression is low, one thing that I have done in the past with some LIMITED success (as long as it's a ring problem) is removing each spark plug and adding a small amount of oil (less than a teaspoon) in to the cylinder. This can help the rings seal and cause enough compression to fire. Now this is obviously something that you wouldn't want to do just for grins, but I have got stubborn low compression motors to run before by doing that.

Anyway lots of luck.

Cheers,
Firechicken

Ok so if none of this works trash the motor? Ive had it for 2 months now and have done nothing but think of what could be going wrong ill deff try the oil to see if it helps if it dont i dont know what to do

Thanks for everyones help and support!

Well, don't be looking at file 13 just yet. You said you heard it run, so it has to be something fixable. Follow FC's compression check first. You should see something in the 130-180 psi range. Below that, you're gett'n weak.

Did you change the cam or replace the timing chain? If so, any chance you're a tooth or so off?

You said drained the cylinders...maybe it's flooded??? Keep your foot to the floor on the accelerator and see if it pops over after cranking on it. Maybe you're dumping too much gas to allow it to spark.

The only "logical" things it can be is:

1.) No Spark (bad ignition module, coil, no power, gear not engaging, coil wire arcing not allowing spark to plugs)
2.) No Fuel (or too much fuel)
3.) Wrong Timing (distributor, cam in wrong location)
4.) Zero Compression (bad rings, worn cylinders)
5.) The starter is not turning the flywheel (threw that in for fun)

You've just got to rule these things out one at a time. If you really suspect the spark is weak, try a different distributor and wire it up hot to the battery post.

Best of Luck dude...we all have engine troubles...that's why we're here!

tj

Hi,
I had exactly the same problem, my engine wouldn't fire after rebuilding the engine. It turned out to have been two things: First, the ignition was set wrong: to get it to start I disconnected the fuel line und turned the engine only on the starter (took some life out of my battery ;-) and set the ignition 8° BTDC, then I reconnected the fuel line. The second thing wrong was I was stupid enough to leave one of my IMS screws on the carb screwed right in. Set that 1 1/2 turns out and after a turn or two it started. Ran very roughly, but I could set it OK from then on. Before I had set the dizzy right on TDC, and it didn't even fire, that little can make a change for starting it from nothing. Once it runs a wrong timing won't immediatley stop it, but to start it needs the timing failry exact because the engine turns so slowly on the starter. Hope that was some help, Good luck!

ok i think i either need a new starter. or my timing is way way way out of wack. a 600 apm cranking battery barly rolls it over But i connected the pink wre for direct power to the dizzy and i got better spark. So ither i have a bad wire harness or Timing is way out of wack or the starters done. I was going to get a compression gague at my mechanics tonight but he said the starter was screwed. Ill try an new starter and then go from there.

HI,
before you get a new starter climb under the car and try to turn the engine by hand (be careful to disconnect the ignition BEFORE you start! This is not to start the engine, but if you can't turn your engine by hand most likely it isn't the starter being duff, but your bearings gone/too little oil/something fried in your engine. Engines should be turnable by hand, with a bit of force, but smoothly turnable. (just grab the flexplate with gloves and wrench it round.) My 350 has a 240 amp Battery, turns just fine, but compressions only about 9:1.

THINGS THAT CAN BE WRONG IF THE ENGINE DOESN'T TURN ON THE STARTER:

1) startergears worn (you'd hear grinding noises)
2) starter not properly aligned (not likely)
3) battery dead or old
4) poor connection/ too thin cable between bat and starter (don't forget the negative cable HAS to go to a GOOD Engine ground! I.e. Exhaust manifold, a block-bolt,...
5) Battery and/or starter terminals corroded
6) Engine at fault (see above)
7) starter old, not lubed enough, gunged up

I would check these things first, before you spend your money on a new starter. Otherwise you buy a new starter and it was only battery terminals that needed cleaning, your out 200 bucks, feel like an idiot and it didn't improve a thing. Check it out.

Have you changed your oil??
Streets is right - if you had to remove spark plugs to blow out the extra fuel, then your oil has gas in it too. That will cause it to try & sieze.
If you had a running motor when it came out, and all you did was pull the dist. out to prevent damage to it , than all you need to do is get back to the basic's.
Change your oil, you have washed down the cylinders with gas and the rings are dragging. this will make it hard to start.
Then set your timing up again.
Then it should start.

Good Luck

timing is set had a mechanic do that i changed the motor oil and cleaned the cyclenders and the starter is sucking to much juice to roll over the motor so i gots an old started that worked b4 just needs a sulinoid ill just swap them and see how it works im not to ambitious today because i got the flu but tomorrow ill swap for sure then ill let yall know whats going on