h e l p ! starting/shut down trouble. (1 Viewer)

[Riley]

Thanks Bill, I get it. Seemed weird but not really when you look at the circuit. Don't worry about talking down to me, I do have an electrical eng degree of sorts and it's my fault for not thinking it through.

B - I warned my wife and she's fine the pulling the battery post. Knowledge is power and I wanted her to be armed with it just in case. I'll put the $15 contacts on my next order just in case. If I get bored this winter I might just go ahead and do this PM but probably not as I have other mods to get done (CDL switch, OME, sliders, skid plate, hide visa from wife ect...).

I guess the root of the concern is that I had a 84 BJ60 diesel with 200K miles on it and it was dead reliable. The starter did go around 190K though. The thing on that rig was it was built like a tank and very simple. Hardly any wires and hoses and ect....

My new 80 seems a little too techie. It's very nice and all but there is the concern that out in the boondocks some little thingy will fail and I'm stuck. On the 60 if you can get it to crank your off to the races.

The starter on the 80 also looks small and cheap. Oh well. The one in my Camry has 200K miles on it and it's fine..... oh never mind - we did replace the contacts in it last year too.

 

[Beowulf]

Chris Geiger is a regular in the 80s section here on ih8mud and he wrote a great article on repairing Toyota starters. Plenty of pics of the starter bits and pieces.

Here is his article and This thread has additional information.

-B-

 

[Brentbba]

Snow - voice of experience, all bad - repair or replace NOW! I ignored it lika a dumb fawk :whoops: knowing the starter was going (I'm on my third starter now) and ended up frying my alternator as well. LISTEN to the excellent advice you've received on this thread. A remfg starter and remfg alternator go for about $300 each! Add labor if you don't repair or install yourself and you are looking at about $1000 to repair.

 

[Eduardo96FZJ80]

Brent,
Thanks for reminding me not to be a "dumb fawk" and stop puttin off such a simple/cheap repair. I think I will go get the # of my starter and see if C-Dan can produce the right contacts

 

[cruiserdan]

"IF?"...............

Was or wasn't yer console rug "right".........

 

[Brentbba]

LOL!

 

[Eduardo96FZJ80]

Sheeesh,
I believe I was using correct "English", I was not doubting the abilities of the great hall monitor :
and yes my rug thingy was a perfect fit,(tight and snug,and the right color) and the radiator too!

soo do you suppose this # of the starter will produce the correct contacts #9722809-326

 

[landtank]

Lots of post to read and forgive me if this has been covered already. Once the contacts weld the starter stays engaged and continues to turn.

Question: what's the construction difference between a DC motor and a DC generator?


Answer: Basically nothing.

A Generator is a mechanical input electrical output device
A Motor is a electrical input mechanical output device

But the device itself is basically the same! Except the generator has a regulator of sorts attached.


Once the contacts weld to hold the motor engaged if the engine fires up we now have Mechanical Drive to the motor. And as soon as the rpm's of the starter increase beyond that of when it is driven electrically we are now producing voltage greater than 12vdc (no regulator) and piping it directly into our charging system!

Ain't good!

 

[cruiserdan]

Rick,

Excelent explanation . I had forgotten about that. It certainly identifies why things fry when this happens. Well done sir


D-

 

[Photoman]

Rick brings back memories. Back when cars had generators one had to be careful installing them. Connecting the wires the wrong way and they would as you say actually start to run without the engine as a DC motor. Had to be polarized also. FWIW, voltage regulators then were adjustable and you could set the voltage.

I don't know as you are correct on the starter becoming a generator in this case. When a starter normally works power is supplied to the brushes causing the armature to turn etc. (DC motor) To be a generator normally the armature must be turned within the brushes to generate voltage (generator). When the contacts are welded the starter is still being powered through the brushes (DC motor) so does not generate electricity. Not saying that damage will not occur. I've had them go up in smoke and could have caused a fire when I didn't have tools with me to get a battery terminal off. I am no expert. Here is a very simple link that demonstrates the DC motor/generator principle.
http://www.gcsec.org/overviewgenerateelec.htm
Bill

 

[landtank]

When you you start your vehicle you supply 12vdc to the starter solenoid which does 2 things

1. supplies high current 12vdc to the motor
1. engages the mechanical drive to the flexplate

Any DC motor which contains brushes/armature when turned mechanically will produce DC electricity. The voltage of that electricity varies with the motor's makeup and the speed at which it is turned. The faster the rpm the higher the voltage.

When that plunger stays engaged and the engine goes into high idle it spins the starter faster than normal and produces a high voltage situation which will spike the system.

Water is often used to show the consepts of electricity. Just as water always flows down hill, Electricity always flows to the lower side.

 

[ppc]

In this case when the engine starts and runs it will turn/drive the armature. When the RPM is sufficient a critical point will exist where the current reverses and the starter will be a generator.

 

[snowcruiser]

Done. I just replaced my starter contacts and plunger. Thanks for the help! Everything seems to be in order but when I turn on the ignition now I hear a relay under the hood click twice before starting the engine. It could be that I just never noticed this before as I usually do not start the car from outside with the hood open. What is this relay noise? Is it normal? It clicks if I turn the ignition switch on and off. Just making sure I didn't wait too long to replace the contacts and inadvertantly fryed something else. I'm having a anyway.

 

[Beowulf]

Snow,
Glad it worked out OK. You're probably good for another 90k miles now.
-B-