hey guys...

what do you think is wrong here?

same thing happend with the old solenoid so i installed a new one yesterday..was a little better and i could start the engine but today..well look at the video

while testing the circuits the voltmeter (VM) shows the following while cranking:

• 7,5 V - VM connected to battery + and -
• 6,3 V - VM connected to starter battery post on starter and starter housing
• 700mV - VM connected to battery + and starter battery post
• 800mV - VM connected to starter housing and battery -
• 400mV - VM connected to battery - and where its connected to the engine (ground)
• 270mV - VM connected to starter housing and engine block

battery charged...voltmeter showed 12,8V. new solenoid installed..

heres the video:

 

"7,5 V - VM connected to battery + and -"
That is the definition of a dead battery.
12.7-13V with no load
Should not drop under 10-11V at the posts, with the starter going

Turn the engine by hand and make sure it is not seizing from bad bearings, etc. Remove spark plugs and feel the motor.

 

the engine is a recently rebuilt 461cui with no miles on it..so i hope bearings are fine.

tried my buddies battery...12,8V with no load...and then around 7,5V while cranking

came out of a 66 pontiac executive 400cui engine...

 

Would it crank with your buddies battery? If not, I would recheck your battery cables, make sure the terminals are very clean, then very tight. I don't think you should loose a volt on the short run from Bat to Starter unless there is not good contact somewhere. Where does your negative cable attach to the motor?

 

its doing the same with my buddies battery...not sure about the Ah but i need around 75Ah

terminals looking fine and the negative cable is attached to the engine block passenger side ..right below the cylinder head.

noticed some green gunk where the battery cables connect to the clamps.

 

Either bad cables, bad connections, or just a bad starter. If you have 12.8 volts at the battery it should be fine. Is there paint between the starter and the block?

 

starter is mounted to the transmission and i'm sure i covered the surface where it touches the transmission while painting it

did some research and the voltage drop to 7,5V while cranking seems to be THE indicator for a dead battery...which is strange since i bought it 2 months ago...yeah i know..it does not mean a thing

how can bad connections lead to such a big drop? is it possible to smoke the cables with excessive cranking so they get worse every time they "overheat"?

did a lot of cranking to solve several problems with the ignition..i also opened the old solenoid and its got a lot of "weld bumps" on the contacts.

 

The cables will hold up longer than your battery will while cranking. Try putting a good strong charge on the battery and see if that helps. A battery that is all but depleted can still show ~ 12v, but drop to nothing under load. Also, you might consider cleaning the area between starter and it's mounting location. Hmm, light went on - as an alternative, you could hook a ground strap from the block to one of the mounting bolts for the starter.
If the battery won't hold a charge, I hope you bought it from someone that will give you a new one under warranty.

 

Grab a jumper cable and hook from the battery to the starter + terminal and crank it. if it works you have a bad positive wire. If not then do the same for the ground.(one at a time first) If still nothing run both jumpers directly to the starter and crank it. If it works you now know what cable to replace. if still hard to start I'd start tracing the ignition wire and/or the ignition cylinder is shorting out.

 

^Yeah that would be why you keep killing starters.

 

sorry...of course i covered the surface before i painted it.

gonna try with a jumper cable tomorrow

 

What do you mean by this. Pic?
Are you using battery terminals where the cable is held to the terminal by a clamp and 2 bolts?
Like said above, the battery must read 12-13 volts before cranking. Take volt readings while cranking at the battery, and between the engine block or starter housing and the battery cable at the starter.
Also make sure timing is set correctly.

 

You have a voltage drop, so be sure to eliminate the green crap at the cables. It sounds worse than just that, so make sure the engine can be turned over by hand like Octania said. It sounds like the rebuilt engine is stiff or the starter windings are bad.

 

Once you determine your cable and paint situation is corrected, I suggest you replace both the starter and the battery (if required) at the same time. A low battery will kill starter windings and a fried starter will kill new battery pretty quick. Good luck.

 

If you have access to an amp clamp try measuring the amperage while cranking, low amperage and low voltage indicates a battery/cable issue. High amperage and low voltage indicates tight motor or bad starter. If I remember right cranking amps should be around 175 to 200 under normal conditions.

 

this is the green gunk on the battery ground to engine block...

got a spare negative battery cable that i can install today..maybe i can borrow the positive cable from the pontiac

 

Ugh. I am not saying thats your only problem, but it certainly is a problem. I have used those terminals on occasion but that set-up just causes trouble. Buy a good heavy pre-made cable. I make my own, not concerned about originality. I use 0, 00, or even 000 gauge wire. I prefer old welding cable. I crimp on terminals, then solder and shrink wrap. Clean very well before assembling. It may be overkill, but once done I never have trouble with them again, and some of my stuff I have had for 20+ years.

 

I would pull the starter and check it inside. If it looks fine, then I would get some new 1 gauge cables if possible and go from there. A bad starter will KILL your battery quick. I rebuilt a starter that died shortly after, one of the brushes went metal on metal into the armature. Worked fine for a bit, then one day a real slow crank and only start with a boost.

 

Before buying anything try this.

If you have a voltmeter then it should also be an ohm-meter, most of them are now, called volt-ohm meter. Anyway, set it on the lowest setting for ohms, possibly 2 or maybe 20 and measure the resistance of the positive battery cable to the starter if the cables are long enough, you may need a helper. Put one probe on the positive battery post (dig in hard and get a good connection) put the other on the post on the starter (make sure it is clean). You should not measure more than an ohm or two. I suspect that the cable is bad and you will get a measurement in the 100's or more. If you have a third helper have them wiggle the cable at that nasty looking joint you photographed and the measurement will probably change. I am 90% sure it is that cable and you will get the results I projected. Good luck and keep us posted.

 

ok...so the voltmeter showed really low resistance...around 0,1 ohm for the (+) and (-) battery cables.

so i pulled the starter...what do you say?

that wire looks real creepy and you could easily pull off its isolation

 

Well I think we are on the right path here.

Brushes are dirt cheap
natauto.com

might as well do the bushings too
maybe a new solenoid or at least flip the contact ring and posts over.

 

You need to cut a few inches off your cables and clean the lugs and reattach. Looks like your brushes need to be replaced, as Chris stated above.

 

I must admit I was wrong, when I saw the photo of the positive cable end I thought for sure that would be it. That starter is definitely DOA.

 

Toast. The fat lady has sung. Put a fork in it, its done. Time for a rebuild or replacement starter. The green stuff looks odd. Usually the green corosion is a dry greenish white powder looking mess. It looks like that might be some sort of anti corrosion compound or green silicon. Do you have any idea what it is? Corrosion or something else?

 

I have seen brushes used past that wear point, but it's rare. I have seen one worn halfway thru the brush screw. You sure can't have the insulated leads w/o insulation and touching the other parts.

The cable ends are hokey at best
At a MINIMUM lose all the green cable down to clean copper. Better yet, get new "real" cables with proper factory ends. One place not to skimp.

For a given power level [starter], the power used is volts x amps. If the volts drops off, in order to provide the same power, the amps must go up. More amps = more load on everything. The resistance loss is amps SQUARED x resistance, so that gets worse far faster as current draw rises due to falling voltage. Cables are crucial.

 

If it was me and this is not a 100% numbers matching car I would just get a good rebuilt starter and new cables. Maybe a mini starter. Does the other cable have this same type repair terminal on it too? If so replace them both. Sounds like you just put alot of money into your motor so why scrimp on battery cables. Those starter brushes are toast, so would be other components in the starter im guessing.

 

i already ordered a pair of battery cables and brushes.

would love to mount a mini starter...already have a RobbMC starter but its for RWD cars. still waiting for the right starter nose to be CNC'd...$$$

any idea if you can buy the insides / field coils of the starter somewhere? shipping is killing me...100$ to ship a 60$ starter (rockauto)

 

I can supply any parts you may need, but it probably would not be cost effective. You will still need to have the parts shipped. Test the armature and fields. They may be repairable. I can't tell from the pics of course. If the fields are not shorted or grounded the brush leads can be insulated and the fields reused. Test the armature for shorts grounds and opens. If you can salvage the windings, replace the brushes, bushings and either replace or rebuild the solenoid. You can probably just turn the solenoid contacts around and over. At this point , a new drive would be recomended also. Make a list of all the parts needed. Rock auto should have the parts needed. If not I can supply what is needed, but The $60.00 Rock auto may be the best option. If you want to keep it original, then repair it. The brushes look to be from the original starter.

 

did a second inspection and found a worn bushing in the nose..the copper insert is gone so the starter nose got totally worn out. i also found that the armature hit one of the field coils..this cant be right..can it?

i'll bite the bullet and order that rockauto starter for now till i got the right nose for my RobbMC starter.

thank you guys

 

installed new brushes today and fixed the other issues....works like a charm

 

Glad to hear!