12V FRICTION STARTER......EVOLUTION

[XYZER]

 I started to add a 12 volt GM starter after the fact....It is using the same method as the Gast air motors only good old 12 volts instead of air. I modified a used starter off a GM small block. It is mounted to the resilient mount sub frame to keep the engine vibration away from the starter. As with most Listeroid projects it will be an evolution and here is its birth....I have a couple of things I would like to incorporate in the process but I will see what I end up when done....Ideally I will make it foot operated and if I can light foot pressure will activate a glow plug and when heavy foot pressure is applied it will activate the starter solenoid.....not sure where that will end up but here is the start.....



Oh...and how do you get the thumnails to post and when you click on them they enlarge?

[veggie]

That's a really nice starter hack XYZER!
With all the torque in that motor, you should be able to get that rubber wheel smokin'.
In fact, without adequate pressure against the flywheel, that's just what she might do.
Is the rubber wheel keyed to the shaft or did you use set screws?

Nice job!

Cheers,
Veggie

[BruceM]

That looks like a beauty, Dave.  But then, we've come expect that when you tackle a problem!  (For newbies, XYZer is the creator of the offset idler and hollow dipper fixes, and has been kind enough to help others with his solutions.)

What starter motor did you start with, and how bad a job was the Bendix removal?  What did you use for the drive wheel?

Regarding "on" slippage- if the motor on trip switch is only on with full pressure engagement, it should be fine- looking forward to see how you do that mechanically.  You will probably need a microswitch which trips a starter relay. 

I like the glow plug switch idea very much.  You hands and mind are busy enough during a start, and it is so easy to forget to turn off the glow plug, and burn it out.  Even though I rarely do manual-pneumatic starts, I've forgotten and fried my glow plug twice.

[XYZER]

It presently has set screws but will be disassembled for painting and I'll install a 1/4" key to make sure. I'm sure it will smoke if there isn't enough pressure....I won't let that happen.

[XYZER]

Bruce..Thanks....

What starter motor did you start with, and how bad a job was the Bendix removal?  What did you use for the drive wheel?

I got the starter from a kid that is always blowing up motors and they are usually 350ci Chevys. The solenoid bendix removal is the easy part. I had to machine the armature shaft for a mid support bearing in the plate against the fields then fabricate the wheel housing. I will have a lever that pivots on the angled brace under the starter that will apply pressure through a linkage to tang in the middle of the wheel housing. I will need about ¾" of travel on the starter side and it will give me about 3" on the foot activated side.   

Regarding "on" slippage- if the motor on trip switch is only on with full pressure engagement, it should be fine- looking forward to see how you do that mechanically.  You will probably need a microswitch which trips a starter relay. 

I haven't got to the how to switch it yet but don't want to have to have a relay.....I was thinking of a momentary push type switch that a cam can slide over and activate it.....If I can find one that handle the amps...I don't know how many amps the glow plug requires so I may get shot down...the starter solenoid switch requires lower amps I'm thinking. Open for more suggestions....

I like the glow plug switch idea very much.  You hands and mind are busy enough during a start, and it is so easy to forget to turn off the glow plug, and burn it out.  Even though I rarely do manual-pneumatic starts, I've forgotten and fried my glow plug twice.

I was thinking the same...I wanted to free up my hands. I am also trying to keep the starting very simple so the wife could handle it if she had to. Step on the foot pressure until buzzer sounds (glow plug on) count 5 (whatever) seconds step all the way until starter activates remove compression release take foot off when it fires...sounds simple anyway....I am going with a buzzer because it can be kept down with the rest of the switches and stuff and I won't need a light mounted with wires in a visual spot. Like I said... "It sounds simple anyway".

[BruceM]

Thanks for sharing the details DAVE.

I like your buzzer feed back for the glow plug.   I find the common piezo buzzers are too high in pitch, too loud and annoying. I haven't found anything better that's easy, though.  Please let me know if you find something better.

I'm looking forward to seeing how your switches work out.

[Ronmar]

I was thinking about a hand lever for mine with the starter switch connected up to the lever.  A certain ammount of lever pressure would have to be applied to close the switch contacts and rotate the starter motor.  This would insure the drive wheel was firmly in contact with the flywheel before the motor was engaged.  As soon as this pressure on the lever is released, the starter would shut off.  

So to start, one hand pushes the lever toward the engine, which engages the drive wheel and starts the motor all in one motion.  Once the flywheels are spun up, the other hand flips the rack shutoff lever on then the comp release off.  Once it fires, you relax pressure on the starter lever and allow it to return to it's home position.  I don't use a glow plug, but a push button could easilly be added to the lever, then a little training and a 5 year old could start it:)  Press buton, count to 15, push lever forward till flywheel starts to spin, count to 10, flip fuel and comp levers and release start lever after teh engine starts...

[BruceM]

A spring in the drive wheel loading mechanics might be a good way to get additional foot pedal movement after contact with the flywheel, so that a switch is only engaged after sufficient pressure is achieved.  The switch would have to be connected to the pedal linkage before the spring, obviously.  Just a thought.

My glow plug is from a VW Jetta.  It glows very hot, and only needs a few seconds to be glowing brightly.  If the glow plug isn't glowing in just a few seconds, I'd be looking at wiring, connectors, and grounding for excessive voltage drop, or replacing the glow plug.

[XYZER]

My glow plug is from a VW Jetta.  It glows very hot, and only needs a few seconds to be glowing brightly.  If the glow plug isn't glowing in just a few seconds, I'd be looking at wiring, connectors, and grounding for excessive voltage drop, or replacing the glow plug.

Bruce
Do you know how many amps do they need?......
Dave

[BruceM]

Dave, My Jetta glow plug is under 12 Amps when hot, but the cold peak load is what the contacts will see,  so a switch or relay should be rated more than double that.

The air cylinder loading is very easy, if air is available, but a spring load with a physical stop could also provide an preset load pressure.  A softer drive wheel (around Shore A 50) faired to the flywheel via sandpaper provides good traction with a lot less pressure.  McMaster.com has them.

[XYZER]

Bruce,
I did a test run with the starter before I had it welded up to the point I could not change things. The preassure required is far less than I anticipated! It never did slip or tried to .It spins her up quit nicely maybe 150+ RPM. I don't believe it will push it through compression from a dead stop. More test to follow. I found a bargin on 2 starter selinoids,  I will use 1 for the glow plug and 1 for the starter. I'll have a backup if one fails...LOL.
Dave 

[quinnf]

Dave,

That was one of the questions that was running around in my mind.  Does an auto type starter have so much torque right off the bat that it just burns rubber?  Apparently not. 

Good to know.

Quinn

[mobile_bob]

fwiw, there are two different starters available for the chevy small block, one for car the other for truck use
the car unit uses only 3 field coils and the truck uses all 4,

of course the truck starter will produce more torque

this of course if only on the wound field starter and not the pm gear reduction starters.

and these days the rebuilders might have abandoned the 3 coil field in favor of just doing all the rebuilds as 4 coil units
saves shelf space, however given a choice at the parts store it might be to ones benefiit to ask for a truck starter for
a big block chevy, that way you know it has all the right stuff inside.

bob g

[BruceM]

Dave, that's great that the electric motor starting torque isn't causing slipping.  What are you using for a drive wheel, the McMaster product?

[XYZER]

Bruce,
Yes it is a Mcmaster Carr wheel. The same as yours if IRC.

Bob,
Does the number of brushes reflect the number of coils? This has 4 brushes...... I did no research on starters I just picked a common one that was free.......

Torque.....
I mistakenly did my test run with the compression release off and it was already coming up on compression It appeared to stall, maybe.........now I need to tell you I had no solenoid and was using a set of jumper cables I also didn't want to stress the situation and break my tack welds so I stopped and engaged the compression release. It does not have any I am gonna rip this thing apart type torque. It has a nice smooth not a lot of pressure needed acceleration with absolutely no sign of slipping up to 150+ (guessing) RPM. It might pull it through compression if it had a run at it ...not sure.

The test tells me it will work well for sure just to spin it up to start it. It requires hardly any wheel pressure. My foot lever can be downsized(was .5 x .5 stock) so it will flex when the wheel has enough pressure allowing for a stop at the same time it hits the start switch.....We will see....................

If the truck fields fit the same starter I could swap and try....... I'm sure it will defiantly take some ass to push it through compression!

Dave