Cranking issue

[McShagger510]

I used to have this exact problem with my car but it turned out to be a bad cell in the old battery.
Tried my car after work today. 12.5V at the battery after sitting in my cold garage for over a month (new battery replaced in the summer), cranked over with a remote starter button and got 9.3V on the starter pole. Everything works fine.

James

big_ape_balls.jpg (46.94 KiB) Viewed 3687 times

[bertvorgon]

Many thanks to my engineering team, we did need three sets of hands. James did a test on his car, which has sat for awhile, and during cranking got voltage at the starter, on the negative side.

I pulled my starter out yesterday and will drop it off at the re-build fellow, not the same business that re-built mine 2 years ago. I should have paid more attention to the fact that the random issue cropped up not long after the re-build.

Many thanks to RMS for dropping off a box of starter motors, as I will pick one and also take that to the re-builder, just in case mine is totally pooched. Build me a good one!

I had hoped to get out for one more drive, but our weather has been less than cooperative and now snow is predicted, so we will see some salt and brine on the roads.

[bertvorgon]

Back to the drawing board...supposedly my starter is fine!

I am going to buy a new ground strap, just in case it is oxidized where I cannot see it....
I am going to clean the faces where the starter mounts to the transmission......
I am going to get a load test done on the battery......

IF that fails......

Then, I am going to try one of RMS's starters and see what happens.....

If that fails......

[RMS]

http://www.stevestonmarine.com/index.ph ... ry%20Cable
if your buying insulated ground wire stay far away from the prince auto stuff. cut open some ground wire that was on a truck for 2 years (in the weather) and it was black on the inside. the pico auto stuff from da lord seems better but I would go all out and hit up steveston marine electronics and get some marine grade wire or cable with soldered ends

[bertvorgon]

That's a good idea, I love Steveston Hardware, I get a lot of my stainless stuff there. I put some of their boat stuff on my Boler 20 Years ago, and it looks as good as the day I put it in there. I get all my nuts and bolts there, stainless.

Stuff I converted over to stainless on my mountain bike. 10 years ago and rode through every winter, has not rusted one iota.

[RMS]

they had these battery terminal +/- to 3/8th coarse made of brass, affixed by 3 grubs and it had a zerk

just laid out 200 bills on stainless fasteners for a m37 body..... what bolts on your bike did you convert to stainless ? my bmx would eat stainless

[bertvorgon]

Silly question but what is the cable wire size that we use for our positive cable?

[RMS]

I think stock was 6ga, most of you with batteries in the trunk run no2 welding cable for the feed to the starter.

[510rob]

#2 AWG for $2.99/ft ---> https://www.kmstools.com/2-welding-cable-4720

#1/0 AWG for $3.19/ft ---> https://www.kmstools.com/1-0-welding-cable-4719

25ft length of #2 AWG for $64.99 ($2.60/ft) ---> http://www.princessauto.com/en/detail/2 ... -p8257990e

4 oz Corrosion Preventive Wiring Connector Sealant ---> http://www.princessauto.com/en/detail/4 ... -p8039562e

[James]

All right, so my engineering team and I did test # 2.

I disconnected my battery, both at the battery and the starter motor. Then, James drove his truck into the bay, to use his battery.

We checked his voltage, 12.7 volts, and checked the voltage at the starter motor, with jumper cables attached to the positive on the starter, and ground to the block. 12.7 volts across the starter terminals.

We then tried to crank.....SAME scenario...voltage at the starter dropped to .08 and it hardly turned over...I am pulling the starter out tomorrow.....

Wouldn't this test eliminate the wiring as a possible problem??? If you jumped the different battery to the starter and the block, then you are direct....and you still had the same issue - correct?

Did you try a different battery in the trunk with the old wiring???

[bertvorgon]

You are right..I am left wondering if we had a good ground with James's battery to my block.

I am going to pull my battery tomorrow and get it load tested, then go through further cable/ground testing. Going to really clean
the starter.

This system has functioned perfectly for 30 years, so it will be something stupidly basic when I find it.

I SHOULD have checked the battery right off the gitco, making an assumption that today's batteries are like the old days...is stupid...even if it has been on a battery maintainer every time I park it.

[Chickenman]

Something else to check Keith. The Brass contacts in the Starter solenoid. There is a contact T-Buss that connect to the two main studs. After a time, these contacts will corrode. This can cause a high resistance situation. I used to disassemble the solenoid, flip the T-Bar over so it had a new contact surface and spin the two contact studs 180 degrees. Requires unsoldering of Ign & S terminal on solenoid, but no biggy. This made a huge difference in starting the 1200 race cars.

Re-builders seldom repair solenoids and I've had similar problems. Initial high resistance, then amperage draw burns through corrosion and away you go. Weak pull in solenoid coil will cause the same issue. I used to regularly take the 1200 starters apart and service them. These were the small 1.2KW direct drive starters. They didn't like 12 to 1 CR and died regularly. I usually had a couple of spares always ready to swap in at the Race Track. Note: this was back in the early 70's before the days of gear reduction starters.

Lube all the Bendix drives and linkage so it moves freely as well. Weak solenoids were a common issue on early Datsuns and they need all the help they can get.

Do you have a gear reduction starter on your 510? They are miles better than the Direct drives.

[Chickenman]

All right, so my engineering team and I did test # 2.

I disconnected my battery, both at the battery and the starter motor. Then, James drove his truck into the bay, to use his battery.

We checked his voltage, 12.7 volts, and checked the voltage at the starter motor, with jumper cables attached to the positive on the starter, and ground to the block. 12.7 volts across the starter terminals.

We then tried to crank.....SAME scenario...voltage at the starter dropped to .08 and it hardly turned over...I am pulling the starter out tomorrow.....

OK... that pretty much confirms a bad starter as James already mentioned. You're using a second battery, hooked directly to starter and you have the same problem. That pretty much eliminate all of the battery and ground circuit. Datsun solenoids were always weak point. The armature and stators seldom failed.

Back to the drawing board...supposedly my starter is fine!

Ummm... Personally I'd pull that solenoid apart, inspect and service it or replace it with a brand new one. And take the whole starter apart as well. Typical scenario. Take it to a shop for testing... and it works fine. Murphy's Law. Not doubting, ( well actually I am ) but you said it was a different re-build shop. Do you trust them?

The other possibility, although it is a slim one, Is that you have low voltage/high resistance to the starter IGN terminal. That can cause issues with the Solenoid coils. ( Some have two coil windings, one is a Pull In and one is a Hold in coil ).

[RMS]

on your way to the plant can you come by the yard and give a hand with my carbs

[Chickenman]

You still battling with the wagon Robyn?