Starter Solenoid

Indiana_Pilot

Indiana_Pilot

Line Up and Wait
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Nov 2, 2013
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Connersville, IN
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I believe my Starter solenoid is going bad on my 66' Cherokee 180C. I keep blowing starter fuses randomly when starting.. I have checked all wires from the switch to the fuse and then to the solenoid and all are in good condition.

So it seems my old solenoid is about to go... The Part number I have in my manual is 99130-02 (487 169)

I can't for the life of me find a 1 pole solenoid like I have now. They are all 2 pole.. I have read one pole is for the starter switch and the other is for the coil.. I am guessing I would not use the coil terminal.

Is this a suitable replacement?
https://www.aircraftsupply.com/X61-0030.html

Mine is this exact one.. http://skywagoncity.com/index.php/piper-cherokee-140-parts/2011/10/solenoid-starter/
 
The coil insulation has probably broken down with heat and age, and is shorting to ground, which is why the fuse is blowing.

Yes, you can use the Lamar. The single pole solenoid has an internal ground. The Lamar you wish to use requires a short jumper wire from one of the coil terminals to ground (a terminal on the mounting bolt for the solenoid will work for the ground).

I'll try to take a picture of the Lamar master solenoid I just installed in my Husky yesterday to show what that looks like.
 
Capt. Geoffrey Thorpe said:
Wait!!!???? There is a market for a 43 year old used solenoid? That's effing insane. This was a low bid commercial off the shelf part when it was new.
Click to expand...

It'll buff up nicely. :D
Probably better than the Sky-tec solenoids out there that barely last a year or two in service...:eek:
 
GRG55 said:
...Yes, you can use the Lamar. The single pole solenoid has an internal ground. The Lamar you wish to use requires a short jumper wire from one of the coil terminals to ground (a terminal on the mounting bolt for the solenoid will work for the ground).

I'll try to take a picture of the Lamar master solenoid I just installed in my Husky yesterday to show what that looks like.
Click to expand...

Below the picture of my master solenoid installation, showing the jumper to ground (mounting bolt). The wire to the other terminal (with the boot) is the +'ve lead from the master switch.

I've also attached the Lamar wiring instructions for both the positive-on case (this is the way my Husky is wired in the picture) and the negative-on case. You will see there is a jumper needed in both cases, but it's wired differently. Make sure you check your wiring polarity.

Lamar Master Solenoid Install - Aviat A-1.JPG
 

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  • Lamar Solenoids Positive-On Diagram.pdf
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  • Lamar Solenoids Negative-On Diagram.pdf
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Capt. Geoffrey Thorpe said:
Wait!!!???? There is a market for a 43 year old used solenoid? That's effing insane. This was a low bid commercial off the shelf part when it was new.
Click to expand...
Buying a used solenoid is like buying used bandaids. The internals of solenoids wear out, especially the heavy copper contacts that carry huge amounts of current to the starter. Those contacts oxidize with age even if the airplane just sits for 40 years, and they burn a little every time they open when you release the start switch; the coils in the starter generate voltage spikes when the current is cut off, and cause arcing at the contacts.

So many times I've fixed sluggish starter performance by taking voltage drop readings across those big terminals on the solenoid. Anything more than, say, half a volt, is cause for replacement, as it indicates resistance that limits the current flow to the starter. That resistance will aso accelerate the oxidation process by heating the contacts.
 
GRG55 said:
Below the picture of my master solenoid installation, showing the jumper to ground (mounting bolt). The wire to the other terminal (with the boot) is the +'ve lead from the master switch.

I've also attached the Lamar wiring instructions for both the positive-on case (this is the way my Husky is wired in the picture) and the negative-on case. You will see there is a jumper needed in both cases, but it's wired differently. Make sure you check your wiring polarity.
Click to expand...

Beisdes that, mechanics need to see if the ignition switch is an ACS unit. AD 93-05-06 applies to any ACS switch with a start position, and demands a diode be installed on the starter solenoid to suppress voltage spikes from the solenoid coil, spikes that cause arcing and damage to the contacts inside the switch. That damage can cause mag malfunctioning. The ACS/Gerdes service bulletin that brought about the AD: http://acsproducts.co/wp-content/uploads/2013/10/SB92-01.pdf
 
Thanks for all the replies.. I was able to order the correct one.. pretty simple once I looked at it since I just have a push button start.
 
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