455 Olds wont fire !!!

[bobsyourman]

Hello, Im back with another problem i cant solve. Hoping you guys can help me look in other directions..
Just finished building a 455 olds. Hei ignition. Cant get the damn thing to fire. Acts and acts like it wants to but just wont start.
i am pretty sure i have everything hooked up right. As its in a boat and i have another boat with a 327 sbc in it that i just copied. (the wiring)
Let me know if im wrong but as far as the distributor and timing marks and such is just like sbc? As far as seting dist.at tdc where the dampner is at 0* and rotor pointing at #1. with the #1 wire on it?18436572?For the olds as well?
Thinking it could be carb issues as i rebuilt the carb but dont know where or who ever had it before.
Any advise would be helpfull as i am about to pull my hair out !!!
Thanks

[bobsyourman]

Ok so some more info :
I got it to fire but it will only fire with the throttle wide open ? Then stalls out imediatly when you let off the throttle?
I checked the float levels and there right on.
Carb squirts a good shot when you depress the throttle arm.
Theres no gas seaping in when the throttle is in idle position.
I have 8 psi fuel pressure.

Thought this might help?
Thanks

[rambos_ride]

This is a WAG

I know Pontiac distributors turn the opposite direction from a Chevy. Not sure on an Olds so I'd double check the distributor rotation and firing order with #1 on TDC.

[Oldcar_Mechanic]

I agree with what Rambo says and I would also encourage you to be sure that when you put the damper to 0, that you are on the compression stroke.

Ron

[bobsyourman]

Thanks for the help. I did get it to fire up but it dies right away? It just Lights and then dies immediately now.i keep thinking carb but i think i might want to go to the coil and dist. set up?
Do you think the msd blaster coil could be the problem?
I didnt buy a OEM 455 coil because they cost to much?
Just a thought.

[bobsyourman]

Triple checked the firing order and dist placement. Fires up sounds good and dies imediatly.

[Oldcar_Mechanic]

Put a voltmeter or test light on the voltage to the coil and make sure that the voltage is always there with the key on engine off. If you are only getting voltage in the start mode, you have found your problem.

Full 12 volts to HEI, all the time the key is on and not through any resistors or resistor wires.

Ron

[bobsyourman]

Put a voltmeter or test light on the voltage to the coil and make sure that the voltage is always there with the key on engine off. If you are only getting voltage in the start mode, you have found your problem.

Full 12 volts to HEI, all the time the key is on and not through any resistors or resistor wires.

Ron

So i should remove the little white block resistor between my coil and ingnition power source?Because i do have one in there?

[Oldcar_Mechanic]

Well, if you have a standard GM HEI, it should be run on12 volts. You can just check the wire for voltage and see what you have. If you have a resister in line before it, you will drop voltage and it will probably not allow the system to function at peak levels.

I have at time just run a jumper from the battery to the BAT terminal at the cap connection. If the car fires and runs good, you know where the problem lays.

To kill the engine though you will have to disconnect the jumper for the ignition.

Keep us posted.

Ron

[bobsyourman]

Well, if you have a standard GM HEI, it should be run on12 volts. You can just check the wire for voltage and see what you have. If you have a resister in line before it, you will drop voltage and it will probably not allow the system to function at peak levels.

I have at time just run a jumper from the battery to the BAT terminal at the cap connection. If the car fires and runs good, you know where the problem lays.

To kill the engine though you will have to disconnect the jumper for the ignition.

Keep us posted.

Ron Have not had a chance to spend any time on this yet. I will try some more this weekend and see if we cant get it running. Its 110 degrees here! Not great weather to be working on engines out in the sun!!!

[bobsyourman]

Well no luck...... No spark at the plugs!!!!!!I dont have an HEI dist. .. I have the electronic ignition that still requires a coil.( Just thought i would clarifiy that).
Cant even get a sputter out of it now? Is it possible that the point ignition plugs are not hot enough for it? I think points plugs are a colder burn? Not that i dont think it would fire and at the least run with any plug bad or not.
This is the 3rd distributor ive tried in it. Not sure what it was out of other then it was in an Olds.
I have power where i think i need it but still no spark at the plugs? Power to coil and out of coil(new msd blaster coil).
I am going crazy with this thing right now
Going to put the original points dist. back in on sunday and try again.
Maybe ill wise up and go get a new HEI 1 wire dist. for it for $100.00 and save some headache. I'm about to give up on this thing !! Help !!

[Oldcar_Mechanic]

Plugs should not matter.

Did you do a voltage check at the positive side of the coil? You should have voltage all the time there with ignition on.

Did you check voltage at the negative side of the coil? You should have a varying voltage (or a flickering light if useing a test light) while the engine is craking.

Did you check the spark at out of the coil secondary wire? ( the one that runs to the center of the distributor cap) Hold it a short distance from a good ground and watch for the spark. (Prop it up so that you don't get jolted)

Ron

[bobsyourman]

Ok, So went to the junk yard and found a true 1 wire HEI for this thing.. And what do you know?
FIRED RIGHT UP !!!
Bad news is there was only about 10 lbs of oil pressure reading. OUCH !!
So out it comes again for a new oil pump i guess?
Maybe i forgot to put that hex shaped drive rod in there? OMG?
The dist. would rotate from the cam to power the engine but nothing to run the oil pump?
I hate mistakes like that. Better go check it right now!!

[bobsyourman]

Ok, So went to the junk yard and found a true 1 wire HEI for this thing.. And what do you know?
FIRED RIGHT UP !!!
Bad news is there was only about 10 lbs of oil pressure reading. OUCH !!
So out it comes again for a new oil pump i guess?
Maybe i forgot to put that hex shaped drive rod in there? OMG?
The dist. would rotate from the cam to power the engine but nothing to run the oil pump?
I hate mistakes like that. Better go check it right now!! so nope im not losing it the shaft is there?
Looks like a new oil pump going in?

[Oldcar_Mechanic]

Are you sure of the pressure?

Does the engine make noise after it runs for a while?

Ron

[bobsyourman]

Are you sure of the pressure?

Does the engine make noise after it runs for a while?

RonI put a small mechanical guage on the little port above the timing chain and it would only read about 5-10 lbs. This was after i took off the electric one that was reading 0*!!!
Well i fired it once.Sounded good for about 5 seconds then started to act rough and i guess a little noise. Ran it for a total of maybe 8 seconds. Saw 0* on the gauge and shut it off.Nothing sounded like it broke.
Then i put the mechanicl guage on it and started it for another 5 seconds saw very little pressure (like 5-10 lbs)even with a slight rev.and shut it off.
So im guessing oil pumps bad. Its my own fault , I reused a pump i had to save a buck witch was probibly the last engine's demise!!
Just hope i didnt hurt anything to bad already.This time i will be sure to spin the pump with a drill and make sure i have good pressure before i fire it up again. !!!!!

[Oldcar_Mechanic]

Sounds like you have it solved

Ron

[bobsyourman]

Sounds like you have it solved

Ron Thanks for all your help.. Well see what happens later. Thanks