pcard

I just installed a home-made heat shield for my starter. The first two sets of photos are the aluminum template.
The second two sets show the stainless steel shield, covered in reflective material. The new shield is attached to the block using a custom stud which provides about a ¾ inch clearance for the starter wiring.
The shield covers the starter and solenoid, as well as the wiring.
I hope this will solve my heat soak problems on hot days. I also installed a starter relay to give 12 volts to the solenoid.

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More Photos

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Second sets

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Last ones

BlackGold

Nice work. Please let us know if it helps or hurts your problem.


My personal theory is that any heat-soak hard-start problems are caused by heat conduction from the block into the starter, not from radiation from the exhaust. But I'd love to hear I'm wrong.


Either way, recognize that hundreds of thousands of Oldsmobiles were shipped from the factory without a starter heat shield, and they apparently didn't have hard-start problems. Your starter heat may be a factor, but there's something else wrong -- too much resistance somewhere, or timing too advanced, weak battery, weak starter, .....

joe_padavano

Keep in mind that no insulation is perfect, and heat shields work in both directions. It will delay heating the starter, but unless you only drive short trips, eventually the starter will still heat up. Once it does heat up, the heat shield keeps the heat in, so it takes longer to cool off.

A better solution is a relay on the "S" terminal of the solenoid, to eliminate the resistance in the NSS and starter switch circuit. Note that this is much simpler and less intrusive than the Ford starter solenoid fix, and it prevents you from having to use a Ford part in your car.

z11375ss

I run the hi torque mini starters on both my Vette and my Olds. They crank when they're hot or cold. Really well. Nice work by you.

Yellowstatue

That long bolt with the threads sticking out from the starter is a Chebby item, which is where the starter brace hooks up for those people. Our people have a threaded hole halfway up the side of the case for the brace. On '80's Olds, there is a heat shield similar to your design but much smaller and attaches to the block above the solenoid and the previously mention threaded hole. Same hook up as a standard brace. Nice job on the heat shield, it kept you off the streets for a short while.

pcard

Hey Yellow - at the time the engine was rebuilt I did not know the starter was not correct ( I was a juane as the French would say), but found out when I went to put the stock heat shield on. Oh well. If it fails I will put the right one on.
Joe: I have installed a starter relay also. I did not want to put any more holes in the firewall and wanted easy access to it so put it next to the regulator. See photos.
In regard to the high torque starters, note that my issue was a failure of the solenoid to engage and I narrowed it down to two potential issues, that may have been operating together either linearly or separately: one was low voltage being delivered to the solenoid as mentioned above and also in the service manual. The other was heat soak on very hot days.
So I decided to address both, the one with the relay and the other with the heat shield.
Some of the comments relating to the effects of installing the heat shield on the stabilized temperature of the starter/solenoid may be contrary to the thermodynamics operating here.
There are two sources of heat working on the solenoid. One is the heat from the block, transferred by radiation and conduction. The other is the radiative heat from the manifold and exhaust pipe. The block will be at the lower temperature which is hopefully limited by the cooling system. I would expect the solenoid to be well within its operating temperature if this was the only source of heat. Remember it will never get hotter than the block if that is the only source of energy.
The exhaust manifold and pipe are at a much higher temperature. In isolating the solenoid from this source by installing the shield we are effectively setting an upper limit to the temperature of the solenoid to that of the block. This of course assumes that the shield operates at 100% efficiency which it probably does not. The shield itself will heat up and then radiate energy itself, but it will certainly be at a lower temperature than the manifold. It is covered in reflective insulating material and has space for air flow.
As for the shield keeping heat in the solenoid, there is ample space between the shield and the solenoid to allow for convective cooling, so that is not the case.
This is all a thought experiment of course, but heat shields would not be in such common use if they were not effective in reducing the effects of radiative heating.
I plan on driving through some of the hottest spots in America this summer and will share the results.

stellar

A quality starter solenoid goes a long way to reduce or eliminate heat soak related no start problems.

pcard

Hi Mark: any recommendations?

joe_padavano

LS engine swaps are in common use also. What's your point?

Seriously, in your thought experiment, think about the fact that the head shield is designed to block the flow of heat from one side to the other. Since no insulation is perfect, eventually both sides of the shield reach equilibrium. Once the outside is cooler than the inside, the heat shield blocks the flow of heat in the other direction.

z11375ss

You should rig a fan up to blow air across the starter. Like from Walmart! Yeah, that's the ticket! Good luck. It seems you may have your problem solved. I hope so. That is a real PITA when all you want to do is cruise. I had a friend with a GTO with the same issue. The heat shield solved it.

stellar

Hi Peter. It sure looks like you put a lot of time, thought, research, and work into this project. Everything looks so nice, neat and clean. I am curious as to how this will work so please keep us informed when you subject it to a good heat test. I noticed the starter you have is of the later style with the longer narrow portion of field case. I am partial to the elder style with the shorter narrow portion. From the pictures I cannot determine if you have a hi or low torque starter. Some of the fields in the case you have were made of aluminium instead of copper. Some have the copper fields. I refuse to use the AL fields in any starter I rebuild. They were problematic. Solenoids can vary in quality. Some have as few as 100 windings and some have 132 winds. The 132 winds make a great difference in the heat soak problem. Here I prefer the elder Delco solenoids either new or rebuilt or a new aftermarket of known # of winds. There is no visable way to determine, but if compared by weight you can tell just by holding them. If your modifications fail to give the results you need for heat soak problems (no start no sound, or light click) I can only recommend you either carry or buy a starter of known quality. If you have a rebuilder near you he should know what to do to give you a quality part. Just be sure to specify you want quality as the market has leaned to lower price vs quality. As you can imagine quality parts cost a little more.

pcard

Hi Joe: I am relying on the reflective material on the shield to reflect some energy, sort of like those emergency blankets which do not insulate but rather reflect the body's heat. This should result in the shield absorbing less energy and so be cooler. This does work. Try holding your hand in front of a fire (not too close!!!) and then wrap your hand in tin foil, shiny side out, and do it again. You will notice the difference.


Thanks for the advice Mark.

Oldsragger

What about wrap the pipe or the starter in of these..

pcard

There is an idea. It would be hard to implement on the manifold, but the pipe is accessible.
Would this effect the engine performance in any way?

Oldsragger

It will help to hold the heat inside the pipe instead of let it go so much out,but it depends how much wrap rounds u use too, i use this on my custom exhaust that pass a little near the gas tank rear with no problem., and arond the pipe include the heatshield with the starter..maybe its a little difficult to wrap around your pipe without disasemle it first, and get some Steel clamps/string/strips to hold it on place. its easyest to wrap headers and pipe. Most of these products is fiberglass so use gloves when install it

oldcutlass

My question is are you still having issues since your starter repair and the addition of the relay? A good solenoid should prevent this from reoccurring. I've witnessed very little issues with stock exhaust systems.

pcard

Hi Eric: I will not be able to test this out until the summer. I only had the problem on hot days (over 90F). If I have problems when I go on my road trip this year then I will definitely swap the solenoid.

stellar

Well since the sun is going into a 30 cool cycle, you may not need to worry about it for a long time.