Heat soaked starters

[Cadman-iac]

Anyone know why sometimes they were separate?  Seems like in the 90's even Ford got away from that design.  Was it just to make it easier to replace?  Maybe get it in a slightly cleaner and drier location? 

I think it was to keep the cost down, and the design of the starter motor was simpler. It made it changing the starter easier, two bolts and a cable and it's off. The remote relay made it quite easy to jump the starter.  You didn't have to crawl under the vehicle like GM cars.

Adding a Ford relay just puts another item between the starter and the battery. I've never understood why anyone would use this setup.  The only thing I can think of is if the GM starter solenoid were hot wired so as soon as you energize the Ford relay, the starter would crank. Your solenoid wire would go to the Ford relay instead, and a jumper goes from the cable connection on the starter to the solenoid terminal.
The cable wouldn't be hot until the Ford relay energized.
Your wiring would be a little easier to get to, but that's the only advantage I can see. It just makes a lot of work for a little convenience, since you have to basically move the solenoid and relay wires to the Ford relay.

  Rick

[mario]

Here is a link to mad eletrics.

http://www.madelectrical.com/catalog/st-1.shtml

The benefit is that there is no hot wire at the starter until you turn the key. Either by battery or heat soak.
The page does point out that this is not a fix for slow or 'draggy' starters; however, it solved my slow starters, twice.
Ciao,
Mario Caimotto

[Cadman-iac]

Here is a link to mad eletrics.

http://www.madelectrical.com/catalog/st-1.shtml

The benefit is that there is no hot wire at the starter until you turn the key. Either by battery or heat soak.
The page does point out that this is not a fix for slow or 'draggy' starters; however, it solved my slow starters, twice.
Ciao,
Mario Caimotto

 Yep, that's the same thing as I guessed earlier. Lots of work for little to no benefit. The only thing that it makes easier is if you are wanting to crank it from under the hood if you're doing a compression test or something. You can use a jumper switch, or a screwdriver, pliers to activate the Ford relay.

 Knowing what happens to the contacts in a GM solenoid, (and you can disassemble it for repairs), what happens to the Ford relay over time, and how would you gain access to the internal parts to even see what's going on in there?
 It sounds like you're just adding problems instead of solving them.

 Thanks for the link though. Interesting to see how they think it works.

 Rick

[Roger Zimmermann]

Studebaker vehicles had also a separate starter relay. As a small company, did they buy the Ford system?

[E Masters]

In my experience providing all electrical stuff is okay I found the plunger and solenoid clearances were tight. At room temp there was hardly any play so when hot the plunger was locked tight to the solenoid. When it cooled down it was fine.

l had a very old starter and pulled the plunger which was of a smaller diameter. It had a little play so I used that and years later it's still going on strong without issue.

I think the modern solenoids are made from cheaper metal which has more expansion from heat than they did in the old days.

[badpoints]

It is more than ohms law. The strength of the magnets is reduced with heat

[Eric DeVirgilis CLC# 8621]

Is the thinking that this issue is related to the solenoid because as I previously mentioned, I experienced the exact same issue with a '72 Lincoln Mark IV which has a fender mounted solenoid.

It's difficult to imagine a brand new 472/500 Cadillac would've had starter drag when restarting a hot engine so the question is what internal starter part(s) are deteriorating in such a way resulting in slow cranking in these years. The solenoid is basically an on/off switch so I think we're barking up the wrong tree.

[Cadman-iac]

  Eric, and Greg,
I had a starter that was dragging when it got hot that I finally pulled out to inspect it for the reason why. I had forgotten about this, it was decades ago.
When I took it apart, I noticed that it had a thrust washer on the commutator end of the armature that rode against the end plate. It was covered with a coating of a combination of grease and the dust from the brushes as they wear, so it was really "gummy" or sticky. I cleaned it up and noticed that the thrust washer looked like it was made of leather or something similar. I wasn't sure if I should apply anything to it before I put it back together, so I left it dry. It may have swollen from the grease too, not sure though.
It seemed to solve the problem as it didn't drag anymore.

You might want to check the end play on the armature, since everything tends to expand ever so slightly when heated. Maybe because it's new, and "tight", it gets tighter after being heat soaked. Just a thought.

I'd like to know what you find out from the rebuilder if you talk to them about this.

  Rick

 Edit:  To add, it might be that one or both of the brass bushings are either too long, or out of position, meaning that they were not pushed in all the way in the case of the brush end, or pushed too far through the nose cone where it doesn't leave enough end play for your armature. Just another thought.

[Eric DeVirgilis CLC# 8621]

Thank you Rick. I like that explanation but the original poster is Greg Surfas who posted "...starter has new armature, new brushes and brush holders solenoid is NOS..." and is still having the issue.


Thankfully none of my cars are exhibiting starter drag when hot- save for...you guessed it..a 1976. 

[Cadman-iac]

Thank you Rick. I like that explanation but the original poster is Greg Surfas who posted "...starter has new armature, new brushes and brush holders solenoid is NOS..." and is still having the issue.


Thankfully none of my cars are exhibiting starter drag when hot- save for...you guessed it..a 1976. 

Yeah, I realized that right after I hit "post", so I went back in and added his name. Then had another thought and added it as an edit. The second thought is because I've seen bushings that had either moved or had not been carefully installed in the first place.
 And who knows, whoever put it together may not have checked the end play, and it has a too thick washer or too many. Hard to say without actually seeing it.

[LaSalle5019]

Apparently the starter spins slower when hot, right? So, as mentioned, ohms law and magnetic field are both working against you when hot. Starter drag keeps coming up in this conversation. Have you checked the drag both hot and cold? Is there some noise that makes you think it is dragging? If you feel it is dragging when hot, then you have a mechanical problem. I suggest removing the starter and spinning it by hand when cold then stick it in your oven at 225 deg F and let it heat soak as if it was underhood on a hot day after a long drive. Underhood temps are in the 200 - 250 deg F range. Now with some good gloves on, spin it over and see if it is really dragging. Maybe you've already done this. Maybe you can hear which end is dragging so you know where to look for the problem. They are not supposed to drag when hot.

["Cadillac Kid" Greg Surfas 15364]

Got tired of fooling around. Pulled the"new" (rebuilt) HD starter (long case) and replaced it with a PowerMaster geared starter. A bit noisy, but it starts my high compression race car when it's hot so my starting issue should be solved. Pulled the starter (that I just pulled out) apart, and everything looks perfect. All contacts like new, etc. The only issue is that It looks like the field coils are the "low torque (shorter) items which would definitely account for the problem, but IO will pull the armature and verify this. Still going to go to the local rebuilders and I will let the forum know what THEY think.
Greg Surfas

[Cadman-iac]

Still going to go to the local rebuilders and I will let the forum know what THEY think.
Greg Surfas

 Just wondering if you've had a chance to go by your local electric rebuilder and what you found out about your starter.

 Rick

["Cadillac Kid" Greg Surfas 15364]

Not yet Rick. I'm heat soaked here. I haven't forgotten about it and am reminded each time the Powermaster "sings"
Greg Surfas

[Chopper1942]

Ford remote mounted the starter solenoid for more clearance at the starter. 

LaSalle5019 hit the nail on the head.  The heat causes the resistance in the windings to increase which decreases the voltage available for the windings to produce as strong a magnetic field like when the starter is cooler. This decreases the motor's torque applied to the flywheel ring gear to turn the engine.

If the drive end bushing or the front bearing is worn, this can cause the clearance between the field winding magnets and the armature to decrease and may cause them to drag when the heat causes them to expand. If dry this is just extra resistance for the starter to rotate. When hot, if the bearings are too tight, the bearings will expand and increase the armature's effort to rotate.

Shielding the starter greatly decreases the hot soak issue and prolongs the starter and cable life.  Just find late 60's and 70's GM, especially Chevy starters, and you will see heat shields attached to protect the starter, which is very close to the exhaust manifold, from the exhaust manifold heat.

Often the "mechanics" would throw away the heat shields to make it easier to reinstall the starter.  If you see a starter housing with a threaded hole in the side of the case below the starter solenoid and the top end plate bolt has a threaded end protruding about 1/2", that is where the heat shield attached.  It is not that difficult to make a heat shield from aluminum that protects the starter and solenoid from excessive exhaust heat.

If none of the above work, you can run ducting from under the front bumper to direct air across the starter when you are driving down the road. This will dramatically lower the temperature of the starter.

[Cadman-iac]

  Greg,

 I'm curious to know what you found out from your rebuilder on your starter issue. Did they solve the problem, or was there another cause for it?

 Rick

["Cadillac Kid" Greg Surfas 15364]

Rick with that Powermaster I don't have any problems so the urgency has sort of slipped. A visit to the local starter/alternator shop is still on my to do list and I haven't forgotten about it.
Greg Surfas