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engine turning over too slow. Whats the problem???

15K views 49 replies 35 participants last post by  ERV JR 
#1 ·
I'm trying to diagnose this problem to decide where to go next. The car was just totally rewired so I know that all connections and grounds are solid. The car turns over fairly slow IMO, even after the new wiring job. I'm looking at getting a new starter, but dont want to get one and still have this issue. We run 2 12 volt batteries and they are brand new. I hear a lot of cars turn over super fast and wondered is it the starter or the fact that they have 16 volt batteries?? Would getting a Powermaster Ultra starter cure this and spin the motor over faster, or is going to 16 volts the only way to accomplish this. I also have the MSD pulling 20 degree on the crank up, and it still spins over pretty slow.
 
#3 ·
A few more details about the motor might help....


I have a "jegs" brand mini starter that I paid less than $100 bucks for on my junk, been on it for 5 years now, it spins my 13.8-1 496 BBC fast as hell and only with one 12 volt battery.....

Sounds like your starter may be tired and drawing high amps, time to chunk it......
 
#7 ·
Bet a buck that it's a bad ground. Is the motor really well grounded? For giggles, try connecting a jumper cable from some solid point on the motor to the frame or better yet the battery and see if it spins faster.

You also had it rewired, is the starter wire beefy enough? Is it getting hot when you spin it? If so, it's too small a wire.
 
#14 ·
get a volt meter and hook it to the batt one at a time and crank the motor the voltage at the batt shouldn't drop to much less than 10 volts it it does then the starter is bad or your cables may be to lite of a guage and /or too long to support the load as far as grounds you want to have a ground from batt to frame and one to body and one from frame to motor ....hope this helps if you can also load check the batts some times new ones are bad
 
#23 ·
get a volt meter and hook it to the batt one at a time and crank the motor the voltage at the batt shouldn't drop to much less than 10 volts it it does then the starter is bad or your cables may be to lite of a guage and /or too long to support the load as far as grounds you want to have a ground from batt to frame and one to body and one from frame to motor ....hope this helps if you can also load check the batts some times new ones are bad
^^^^ This ! Get another starter to try.
 
#16 ·
20degrees on crank up? I would put only 4 or 5 degrees at max! Your going to take the flywheel & starter out with removing that much at crank up.
Ultra torque powermaster, Tilton or meziere starters...spend your money one time if it is a starter problem.
I seen people replaced starters, wiring, batteries but forgot to do a simple check in the oil filter....my 2 cents!
 
#47 ·
x100000.In 3 minutes max you will kno exactly what got overlooked.Good luck and post the fix.
 
#21 ·
does it have a ford style solenoid- did you replace it........they can be bad out of the box and will wear out......also if the rewire guy tightened the starter cable down enough to twist the post in the housing it will do the same thing.........
 
#24 · (Edited)
Your best best is to run a Negative cable up the the front of the car as well as the Positive. There is less resistance in the properly sized ground versus the Chassis Ground. The power and consistancy you gain from the ignition, other electronics and the starter will more than make up for the weight. You need to, as previously mentioned, tie the block into the Negative cable. I use both Positive and Negative bulkheads.... I would run a jumper cable temporarily for testing purposes from the block to the Negative post. I have also seen the ignition retard issue as well. Although more seems better, it is not always the case.

Mike
 
#25 ·
What is the gear reduction and hp of the starter your using? thats why different compression motors will use a different gear reduction to get the motor cranking, if you pull 10 or 20 degrees out (using a msd type starter retard) it should crank over faster.
 
#28 ·
this will help u alot.........Voltage drop testing is one of the simpliest tests in the world to do, but often is over looked. Here is a detailed explanation of how to perform the test.

You will need a volt meter, prefferable a digital one. The help of a friend will make testing a lot easier as well. And possibly a set of booster cables if the circuit you are going to test is really long.

A few things that you should know first. When you use a volt meter it displays the difference in voltage from one lead to another. So when you place it across the battery on the + and - posts, and it reads 12.79volts, it means that the difference in voltage between the two posts is 12.79volts.

All the circuits in your car complete themsleves at the battery, specifically between the + and - plates inside the battery. So any extra resistance outside the battery, any where in the circuit is a bad thing.

Industry stanard for automotive production cars is a .5 total voltage drop in any system. Except maybe your starting system, as the old style starters just draw a ton of amperage. The .5 is divided up as .3 positive and .2 negative. So when we are testing the positive leg of the circuit we will want to see less than .3 of a drop, and less than .2 on the negative side. This is while the device is in use. i.e. if you are checking your lights, they need to be on while doing the check.

So here is how to do the test. Put one lead on one point of the circuit, and the other lead at another point. Say at both ends of a wire. The meter should read zero. Now turn on the device. The reading on the meter is how much the voltage drops between the two leads. If it is on both ends of a wire, then it is how much the voltage drop down that wire. If it is over .3 + or .2 - it needs to be replaced.

Here is an example testing the starter system on an older Ford. It is slow cranking, with a new starter and battery, so we will check for voltage drop issues. First thing we do is put one lead on the positive terminal of the battery, and the other lead on main post of the starter. Try starting it and we get a reading of 1.5volts. So we know there is a 1.5 volt drop on the positive side of the circuit.

So leaving the lead on the battery, we move the other lead up to where the main battery cable from the starter goes to the fenderwall solenoid. We repeat the start, and still get a reading of 1.5volts. So we know that cable is not the problem. (Could have also put the leads on each end of the wire to determine this, but takes longer to do the test).

Next you put the lead on the solenoid's post, and try the test. Still 1.5volts, so we know the connection between the post and the starter cable) is good. So we move the lead to the other post of the fenderwall solenoid, and repeat the test. Now we get a reading of .5 volts on the meter, instead of the 1.5volts. So it would appear that we are losing 1 volt through the solenoid. To confirm that we can put a lead on each post of the solenoid, and try starting it. In this case it does confirm that we dropping 1 volt through the solenoid.

But we still have .5 volts drop. So now we check the cable end at the solenoid, to the battery post. It reads .5volts still. So we then go to the battery post to the cable end at the battery itself. We get a reading still of .5 . So that would mean that between the battery post and the cable end we are losing .5volts, in other words, we have a bad connection.

So you replace the solenoid, clean the battery cable end at the battery. Also preventive clean the solenoid cable ends too. Test the complete system down to the starter again, and get a reading of .2 volts. So we are happy. Moving over ot the negative side. You move one lead to negative post of the battery, and another lead to the body of the starter.

You start the motor and getting a reading of .7 on volt meter. Now you just follow the ground path back every where there is a connection. So first you would go from the negative post to the bell housing, then block, then the ground strap clamp at the block, then to the frame rail, etc, etc. Where ever the drop goes away, then the what ever is between your last point and the new point is likely where the drop is. Always double check it by actually putting the leads on both ends of the item being tested (both ends of a wire, between a clamp and bolt, two posts on a solenoid or relay, two posts on a kill switch, etc).

It should take less than a couple of minutes to check a complete circuit. If the circuit is really long, say with the battery in the trunk. You can clamp a booster cable to the battery, and then to the one lead of the meter, thus extending the lead's length. You can use a small wire even, just booster cables are readily available.

Now when my youngest daughter was 5 or 6 I taught her how to do this test in less than 5 minutes. When we do seminars with licensed mechanics with years of experience, it takes 1/2 hour to an hour to explain it. i.e. do not over think it, it is really, really, easy. You should do it on any circuit you install, and it does not hurt to go through your car, daily driver included every now and then.

If people did they would have found that the GM hot start in the 70's was mostly because the 4ga starter wire needed to be 1ga starter wire. Or late 80's, early 90's GM pickups (and others) could have almost an extra whole volt in their ssytem if they replace the too small charge wire, as it dropped .7 to .8 before going to the battery. Or Ford Super Duty's eating starters because the main battery cable corroded about 12" back from the starter. The end at the starter looked great, but lots had 5 volt drops down them.

Hope this all made sense, if not I will try and clarify below.
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If anyone needs to reach me for Tech my home email is razor1966@rogers.com or 1-888-214-7774 . Dec 09, 2010
 
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