73-87chevytrucks.com

73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: Layne on May 02, 2009, 09:20:21 pm

Title: rebuilt 305 wont run
Post by: Layne on May 02, 2009, 09:20:21 pm
just put my 305 in and got it to turn over.  We moved the distrubutor left and right and found a spot that it would start to run and then hiccup a fireball out of the carb. anywhere else and it would shoot fireballs out of the headers.  I then took out the distributer and rotated it 180 degrees and... nothing.  It's got a lunati bracket master 2 cam, gear drive, non computer dis, edelbrock rpm air gap nascar intake and a holley 750 i got for 100 dollars. (I couldn't talk my girlfriend into letting me get a eddi 500 for 350 dollars.) Any ideas? I think it might be the cam timing, but i checked it 9 times before i put the motor in my truck.
Title: Re: rebuilt 305 wont run
Post by: Layne on May 02, 2009, 09:39:00 pm
77 c-10 82 305 86 700r4
Title: Re: rebuilt 305 wont run
Post by: VileZambonie on May 02, 2009, 10:35:29 pm
Sounds like you were off a tooth. Put it on TDC compression and reinstall the distributor.
Title: Re: rebuilt 305 wont run
Post by: Lt.Del on May 02, 2009, 10:37:35 pm
or....double check spark plug wires to ensure installed in proper order...18436572
Title: Re: rebuilt 305 wont run
Post by: Layne on May 02, 2009, 10:38:35 pm
can't you compensate for the ign timing by twisting the dis? I'm kinda confused with the tooth thing. Sorry. lol
Title: Re: rebuilt 305 wont run
Post by: Layne on May 02, 2009, 10:39:03 pm
checked and quadruple checked
Title: Re: rebuilt 305 wont run
Post by: VileZambonie on May 02, 2009, 10:41:55 pm
No, So start over and line up tdc compression.
Title: Re: rebuilt 305 wont run
Post by: Layne on May 04, 2009, 04:50:53 pm
set the distributer in and timed it at 8 degrees and it still won't run.  Is it supposed to be at 0 or 8 when you first start out?
Title: Re: rebuilt 305 wont run
Post by: Captkaos on May 04, 2009, 05:17:10 pm
Drop it in with #1 on TDC and leave some room for advance,
Set timing at 10 degrees and work you way around from there.  It will probably hit around 12 degrees for a stock motor.
Title: Re: rebuilt 305 wont run
Post by: exilous on May 04, 2009, 08:36:07 pm
I had that same problem in my 85 blazer 305 it was 1 tooth off but if i cranked the distributor way out it would just barely run...then uhm well it just stopped and wouldnt run anymore...I was still learning about it the day i got it home i figured out the whole tooth off thing after the engine died.
Title: Re: rebuilt 305 wont run
Post by: Layne on May 04, 2009, 09:24:06 pm
rockers were too tight! lol loosened them up and I got compression. should have checked the compression earlier! Thanks for the help though.
Title: Re: rebuilt 305 wont run
Post by: 1976Scottsdale on May 04, 2009, 09:59:19 pm
rockers were too tight! lol loosened them up and I got compression. should have checked the compression earlier! Thanks for the help though.
Gotta watch those.  Otherwise that bracket master will be coming right back out.  Its not even fun til the lobes flatten so bad that the valves start opening on the back side of the lobe... still get nightmares... Mommy!?!
Title: Re: rebuilt 305 wont run
Post by: Layne on May 06, 2009, 04:20:49 pm
today i went to break the cam in and i started out at 80 oil psi and 4min later i had 20... I killed the truck and looked underneath and I've got all five quarts on the ground!!! So i looked around and found the front of the intake is leaking a litte oil and so is my rocker cover.  I looked behind the motor and oil is everywhere.  Which would be more likely- the back of the intake or the rear main?  If it is the rear main do I have to pull the motor or can i get the pan out without pulling my engine?
Title: Re: rebuilt 305 wont run
Post by: eventhorizon66 on May 06, 2009, 04:26:36 pm
Did you use the cork end seals on the intake or RTV?  I use TheRightStuff RTV (about a 3/8" bead) and have no issues with leakage.  Grab a new set of intake gaskets and try that first.  If you do have to drop the pan, you can do it with the engine in the truck no problem, I did this not too long ago.
Title: Re: rebuilt 305 wont run
Post by: Layne on May 06, 2009, 04:34:51 pm
i used a cam change kit from mr gasket i think. edelbrock said not to use the rubber end seals on the intake and just glob a bead through there. I used rtv red.
Title: Re: rebuilt 305 wont run
Post by: eventhorizon66 on May 06, 2009, 05:21:52 pm
Also, there is a dye you can put in your oil to detect the source of leaks.  You might give that a try.  But if it's a fresh rebuild and the block is nice and clean (?) you should just be able to feel around back where the the intake meets the block in the back to see if that's where it's leaking.  It could also seep past your oil pan gaskets at the corners where the pan.  Did you put a squirt of RTV at each corner?
Title: Re: rebuilt 305 wont run
Post by: Layne on May 06, 2009, 05:28:16 pm
yes. i used a whole thing of rtv for the whole motor. it's still kinda warm so i haven't got to snooping around the truck too much. I just hope i don't have to drop the pan. want to go out and drive lol
Title: Re: rebuilt 305 wont run
Post by: VileZambonie on May 06, 2009, 06:42:29 pm
Do you have an oil pressure sending unit installed near the distributor?
Title: Re: rebuilt 305 wont run
Post by: eventhorizon66 on May 06, 2009, 07:34:30 pm
Do you have an oil pressure sending unit installed near the distributor?

LOL, that might explain the geyser shooting out of the back of the engine.
Title: Re: rebuilt 305 wont run
Post by: Marc on May 06, 2009, 08:09:12 pm
To lose 5 quarts in 5 minutes you must be missing one of the oil sending units!  either the aforementioned one by the distributor or down by the oil filter.  That fast it should be easy to spot.
Title: Re: rebuilt 305 wont run
Post by: Layne on May 06, 2009, 08:36:17 pm
mechanical autometer gauge. It had good pressure, and then it just dropped like a rock.  my friend was helping me time it and it didn't leak or anything till it got up to about 180
Title: Re: rebuilt 305 wont run
Post by: Layne on May 11, 2009, 11:29:43 pm
I pulled the intake off and my end seals weren't quite up to par and I forgot the ferrule in my oil line for the gauge.  Even though edelbrock said not to use the rubber end seals I was thinking about putting them on. Any suggestions?
Title: Re: rebuilt 305 wont run
Post by: eventhorizon66 on May 11, 2009, 11:51:49 pm
I use a thick bead of TheRightStuff and it works great.  Clean both the manifold and block mating surfaces thoroughly.  Run about a 3/8" thick bead of RTV along the rails and make sure you overlap the gaskets a little on either side.  Also be sure to drop the manifold straight down into place the first time.  If you move it back and forth too much after setting it down, you will disturb the RTV.  The bead of RTV should be thick enough that when you torque down the manifold it sqeezes out a little.  Then run your finger along the ends to clean up what has squeezed out and you're done.  I also smear a thin bead of TheRightStuff around the water passages on both sides of the gasket.
Title: Re: rebuilt 305 wont run
Post by: Stewart G Griffin on May 12, 2009, 09:23:36 am
i know it wasn't the case in this particular situation, but if we could please re-visit the whole "one tooth off" theory.

If the distributor was put in "one tooth off," then couldn't turning the distributor slightly so that the number#1 terminal on the distributor cap lines up with the rotor when the engine is in #1 TDC be okay?
Title: Re: rebuilt 305 wont run
Post by: ccz145a on May 12, 2009, 10:45:24 am
i know it wasn't the case in this particular situation, but if we could please re-visit the whole "one tooth off" theory.

If the distributor was put in "one tooth off," then couldn't turning the distributor slightly so that the number#1 terminal on the distributor lines up with the rotor when the engine is in #1 TDC be okay?
Yes, in theory. But in reality some intakes have an ear that gets in the way of the vacuum advance canister and a few of your plug wires might not reach. That is if the distributor being off a tooth.

I think the case here was the timing chain, then your cam is mechanically out of synch with the crank.