Yes I was also thinking his bearings may be to tight .... but if it was professionally done it should be good to go .... seen a few backyard mechanics have trouble with the motor starting after they have run it for a little while my best suggestion is lube lube lube cause that motor will be tight as heck if he did his job right ...... I would see if I could borrow I high torch starter to see if that helps

 

Shortblock of motor was professionally built with the crank polished to specific tolerances I assume. I was curious of clearance on bearings and was meaning to ask the machinist what they were. They should be the proper i'm confident of it.
With the plugs out I was able to turn the motor over with a 1/2 drive socket while it was still on stand. It took some force but turned no problem. Oil pressure seems high but the thing is brand new. Should be ok.
I really want to fire this thing but again just busy. I havnt even takin off that ground wire to coil. Its dark when i leave for work and dark when i get home. I have been redoing grounds the other nite with my halogens on a stand double checking for the cleanest connection possible. O forgot to mention the only part my bro installed was the starter and he stripped the stud. it was semi tight and I tapped it with a die to 5/16 coarse thread and got a good solid connection now. It was definetly better but not a good fast crank.
I''l get it going soon enough...
Thanks for the tips guys

 

So this was a fresh rebuild? I would be concerned about the condition of the cam now unless you're running a roller cam.

The engine needs to fire immediately and brought to 2500 RPM to break-in the cam and provide the needed lubrication. With all the constant spinning of the crank I would be a tad bit worried.

Josh

 

Oh, and I am running over 10.5:1 compression with a stock starter that is at LEAST 17 years old and it cranks perfectly fine, hot or cold.

Also 16-18 degrees initial timing.

Another point, you have the + wire to your Crane coming from a key-on, key start? If it is only key-on you aren't getting voltage during crank (key start).

Josh

 

(+) is key on ignition but I have a over ride switch directly from battery on a toggle that I flip on to override aux fuse box for power as it does lose power when key is cranked. It works and is kinda a theft device as well.

As for cam Im not too concerend I really havnt cranked on it for long periods of time and when it was it was slow going.. That is why I'm looking for answers and not guessing around too much and over cranking it.

O and why do you not get power on a key cranked to start position? Is there a better option for wiring coil??

 

I would be a little concerned, guys are wiping out cams like crazy these last few years, it doesn't take much.

As for the coil wire, I would personally just eliminate the "pink" resistor wire by bypassing it, therefore keeping the ignition system in the OEM circuit.

Or install a temporary points distributor and get the engine running and figure out the aftermarket stuff later.

Josh

 

I'm having a similar issue with my rebuilt 390: struggles to start cold or hot. Only got a couple hours and 20 or so miles on it so far. Temps running in the 20s these days. During break-in, we figured it was electrical, so bumped the amps with a starter pack. Don't know for sure that it helped all that much.

The ground cable that was in there got lost at the shop where the motor got machined, so we rigged an old battery cable between the alternator and battery (-). I installed a new strap tonight anyway. I'm hopeful it may help a little when I start her again over the next couple days.

 

Ok you said the battery cables are new 1ga units BUT what about the ground? Is it from battery to the block? Did you sand off any and all paint where it bolts on? do you have a ground strap from the engine to the body/frame of the truck? Slow cranking is very often a poor ground much more then the compression. I was able to turn over and start my 13.4:1 compression 528 stroker big block with a old (as in 20+yr old) stock starter when my high torque unit broke. But when I had a bad ground even the $250 hi torque gear drive unit struggled.

 

Only ground i'm missing is batery to body. Everything else is big 1 gauge. Dual batteries both grounder clean on each frame. Come to think of it only one battery is grounded to block and it's my aux one. I have the batterries hooked in series on a switch but I should ground the main to the block as well.. Hmm. I'll pick up some more solder on end lugs. I have a roll of about 80' of high quality 1 gauge multi strand cable my budy gave my from the hydro company so I'll use that... I'll give it another go tonight

 

yeah grounding to the frame is the WORST place you can ground to. Your motor mounts insulate the motor so the ground has to travel from the frame, to the suspension components, through the differential up the drive-shaft and through the transmission before getting to the motor. the metal in the frame is only about half as good of a conductor as copper wire AND it has to travel through spaces like the U joints (and usually takes them out in short order)

Batteries should never be ground directly to the frame, always ground to the engine block first and then to the body and if you feel the need to the frame. (I almost always do ground from the block to the frame with a large grounding strap personally)

 

Ok here is exactly what I run ...
Main battery - to frame .+ to painless dual battery solenoid,solenoid to starter solenoid.
Aux battery - to alternator bracket(block) and frame. + side again to painless solenoid. painless switch was set so batterries were connected
So i guess if the aux battery is grounded to frame and block and main battery is grounded to frame then the main is grounded to frame through the aux side block ground.
This all sounds just confusing but I will ground the main to the block as well and then also add another cable from body to block but I just planned to use a 8 gauge wire for that which is like 1/4'' o.d. with heavy coarse internal wires vs multistrand. I didnt think the body one needed 1 gauge I already will have enough cables under the hood
Also my driver side motor mount is modified so instead of the reciever portion in stock form that bolts to block and rubber piece with pin bolted to mount , Ive made it so the mount bolts to the block with a stud connected so its actually a bolted connection and not just resting in the holder. I have a rubber cab mount between the block and mount for a dampener but the bolt is still somewhat grounded as it bolts up but i didnt clean the inside of the mount for a good connection. i did this cause the first time i took out my nw 390 I went all out up a snow covered hill and the motor jumped out of its mount and my clutch linkage came undone. I dont understand this DUMB design. Having just the driver side mount a permanent bolted connection solved my problems now offroad even when I rolled the truck in a competition.. Anyways thats a whole other topic I just need to fire this thing up. I finally got a day off tomorrow and I'll do my best to get it going...

 

btw you have the batteries hooked in parallel not series.

Series would double your voltage and is done by hooking the negative to one battery to the positive of the other then the neg of that battery to the ground of the vehicle. You only have 1 positive and 1 negative hooked to the vehicle when in series (no matter how many batteries you run) the other positive negitive are hooked together.

 

ok sure. Shows how good I am at electrical stuff!!

 

Frame frame or firewall?

 

As for cam concern again, I'm running a 391 9qt oil pan so I run it with 2 bottles of comp cam zinc oil additive..
I'm going out to try to fire this now