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Discussion Starter · #1 · (Edited)
Newly built motor, never fired. I've had it together for months with the spark plugs out. The starter turns the motor over and I've spun it to build oil pressure and prime the fuel pump. Even when the plugs are out, the motor turns over more slowly than my other SBC does when starting. Then I put the spark plugs in and it'll get maybe half a turn and stop. And then I can press the starter button again and get another half turn and it stops. When it stops (with the button still pressed) I can hear the starter buzzing.

The motor is a 383 with 11:1 compression. It has a Quartermaster triple disk setup with reverse mount starter (used from Ebay). Battery is a new 640 CCA AGM battery.

I can turn the motor over by hand with the plugs in. It's pretty hard with just a regular 1/2 inch ratchet. I can get maybe 1/8 of a turn and then I have to let the pressure bleed off.

I pulled the 800 CCA duralast battery out of my car and crawled under the race car with jumper cables. One end clamped to the bellhousing and the other end to touch the pole on the starter. This works even worse where the starter won't turn at all which is surprising.

Here's the kind of starter setup I've got:

616026
 

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Discussion Starter · #2 ·
New motor, never fired, new rings, forged pistons

Turning the motor using a torque wrench on the crank bolt:

  • No spark plugs - rockers loosened ==> 40-45 lbs
  • No spark plugs - rockers tightened ==> 60-65 lbs


That feels about right. I don't think my motor is putting up too much resistance. I think its the starter.
 

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Discussion Starter · #3 ·
With the battery in the rear of the car, I measured voltage at a few different places when cranking:

  • Not cranking - 12.7 V
  • Cranking, at the battery - 11.5 V
  • Cranking, at the the ford-style solenoid in the front of the car - 10.5 V
  • Cranking, at the starter - 10 V

I got out some short battery cables with terminals and went under the car with the battery.

With the plugs out, it spins quite a bit faster with the battery under the car.
With the plugs in, it also spins maybe a turn or two before quitting.

I measured the voltage at the battery (with the battery under the car and 2' cables) when spinning the motor with plugs in - it also drops to 10 volts.

So I don't think it is my wiring.
 

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I read this when it first posted and have been cogitating while moving the compost pile. I see at least three possibilitie.

First is a question as to whether this cranking is with ignition on or off? If on then I can say with big cam engines that need a lot of base advance it then is likely your cranking against early burns in the cylinders. A help for this is to divorce the ignition from the cranking.

Second is whether your compression ratio aritmatic is accurate at 11 to 1. Given even you can’t get it over TDC with the plugs installed, not that it should be easy but with a breaker bar and the slow speed of hand cranking one would thing you can pull an 11 to 1 engine through TDC.

Third is a larger one with goodness of the starter, sounds like you need and old time automotive electrical guy with a test bench to see if the internal wiring is good. One can add brushes, grounds, the relay’s switching contractors being clean and sturdy, shaft bearings not dry or worn, clearance between the stater’s pinion gear and the flywheel ring gear being correct add to that physical alignment. The fact that applying more voltage seems to make it worse is something that could lead into clearances and alignments.

Bogie
 

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Discussion Starter · #6 · (Edited)
I read this when it first posted and have been cogitating while moving the compost pile. I see at least three possibilitie.

First is a question as to whether this cranking is with ignition on or off? If on then I can say with big cam engines that need a lot of base advance it then is likely your cranking against early burns in the cylinders. A help for this is to divorce the ignition from the cranking.

Second is whether your compression ratio aritmatic is accurate at 11 to 1. Given even you can’t get it over TDC with the plugs installed, not that it should be easy but with a breaker bar and the slow speed of hand cranking one would thing you can pull an 11 to 1 engine through TDC.

Third is a larger one with goodness of the starter, sounds like you need and old time automotive electrical guy with a test bench to see if the internal wiring is good. One can add brushes, grounds, the relay’s switching contractors being clean and sturdy, shaft bearings not dry or worn, clearance between the stater’s pinion gear and the flywheel ring gear being correct add to that physical alignment. The fact that applying more voltage seems to make it worse is something that could lead into clearances and alignments.

Bogie
Thanks for the thoughts!

Ignition is off. I've done the compression ratio a few times with different calculators. 4 inch bore, 3.75 stroke, 0.025 in the hole at TDC (stock block), 0.015 shim gasket, 64 cc heads, 5 cc valve reliefs in the pistons. I did a compression test on one cylinder and it topped out at 140 psi after 5 cycles.

This starter is supposed to crank up to an 18:1 motor!

I think the starter is bad. Thanks to Amazon, I've got another one coming next Wednesday with free returns.

I'll pull the starter and bench test it again. But I remember it jerked and whirred real good when I tested it on the garage floor.

There are a couple bolts on the back of the starter motor. I was thinking of taking it apart to inspect the insides and see if anything looks obviously wrong (like burns). I shouldn't need any special tools to get it back together, right? I'd hate to take it apart and have a bunch of small parts and springs go flying and not be able to get it back together! :)


Thanks!!
 

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Discussion Starter · #7 ·
According to Quartermaster, the current draw on this starter is 210 amps at rated load. An online voltage drop calculator said 10 foot of 1 gauge wire should have only a 0.6 volt drop.

I'm seeing a 2.75 amp voltage drop. The calculator says it would take like 900 amps of current draw to create that much voltage drop! Even if my numbers aren't exactly right, I think that this is way too much voltage drop for a starter that is supposed to consume 210 amps at max load.
 

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1949 Ford Coupe RESURRECTION
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I had the same issue when I built my 383 and used the starter that the guy had when I bought the block. Bought a new starter. All is well now.
 

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Discussion Starter · #10 · (Edited)
I took apart the starter and was happy to find an electrical short inside of it. The main positive terminal leading into the motor case has the insulation worn away and I could see on the brush assembly where it was arcing. I repaired the insulation and put the starter back in. With the battery under the car and 2' of cable, it worked! Turned over with the plugs in.

I returned the battery to the back of the car to test it. And to my disappointment the starter DID NOT work. Hmmm... so back under the car with the battery and that still worked. Then I started working backwards up the wiring path. When I put the battery directly to the starter-side of the ford solenoid I've got mounted inside the car (so the power doesn't go through the solenoid), the starter worked but it was slower. So the additional 4' of wire was enough to slow it down. Then when I put the battery on the other side of the solenoid (so the power goes through the solenoid), it stopped working. Then I put the battery in the back of the car and went around the solenoid (so power was going straight from battery to starter but using all of the car's cabling including the shut-off switch but not the solenoid), and the starter didn't work. Taking the solenoid out of the equation didn't fix it. So I don't think it is any particular wire or the solenoid that's the problem... it just seems that the more cable I add in the path, the weaker the starter gets.

I believe that even though I fixed the visible short in the starter, it is still bad. And it is still drawing so much current to create a massive voltage drop when running through the 12' of 1 gauge wire I've got in the car.

Got the new starter coming in on Wednesday. I'll stop fiddling around and see if that fixes it :)

616065
 

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Volt drop is pretty normal with a high compression engine, I find it common with 10.5 and up engines to see the B+ volts to drop to around 10 to even as low as 8 while cranking.

Given that I also rebuild antique and vintage radios I spend a lot of time with volt and amp meters. Even the best of the best need to be sent out for calibration. There is often non linear read out variation from instrument to instrument that is also temperature variable. This is much more common in the lower voltage ranges say from 50 volts down to fractions. So among all the other problems in the world you can add accuracy of meters and gauges to the list.

Bogie
 

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Race it, Don't rice it!
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Question, the starter already has a solenoid/relay, Why add a another relay? You don't need two relays in the same system.
One more thing, barely cranking while cold, may not crank when hot.
My advice, QM and Tilton are the only ones I'll ever use. Everything has caused too many problems for me. Expensive yes, So far you have bought two starters already.
 

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the reason for the Ford solenoid is to eliminate having a large Gage wire running through the car when it's only needed for starting.
 

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Discussion Starter · #16 ·
I ordered a clamp DC amp meter to see how much current this bad starter is drawing. And wouldn't you freaking know it... today when I went out to test it the dang thing cranked the motor (with plugs in) just fine! Nothing's been touched since I last tried the thing... its just sat for a couple days.

This forum used to have an emoji of a guy hitting himself in the head with a hammer. I can't seem to find it... but that would be appropriate right now.
 

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Yes they are and the bad part is they tend to come back at the worse time.
 

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Discussion Starter · #20 · (Edited)
The new starter worked perfectly! It arrived before the amp meter so I never got a chance to measure the amps on the old starter. The Ebay seller was a real stand-up dude and said that I could ship the starter back to them and they'd pay to have it rebuilt by Quartermaster. So that's is already off in the mail. I'll prolly keep the new starter on the car and hang on to the rebuilt one as a spare... maybe sell it one day.

Just glad the motor turns over now. Onto the next problem! :)
 
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