Author Topic: Cowl Hood Solenoid Testing and Fixes  (Read 1872 times)

WaltZ

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Cowl Hood Solenoid Testing and Fixes
« on: December 06, 2020, 04:51:35 PM »
Keep your #1114427 solenoids.
This may be of help who have issues with the cowl flapper/solenoid.
This was driving me crazy as it would test out fine on the bench and than not work when reinstalled...
Instead of replacing, it may be repaired while keeping the original unit.
Sorry about no pictures of this process.

needed: ohm/volt meter, basic soldering iron and fluxed wire solder

A: fuse keeps blowing.. check to be sure the terminal pushed on to the solenoid is not too far. It can ground out to the solenoid's main case.
 
B: before getting to the solenoid, turn the key to run, be sure to check for power coming from the relay. Disconnect throttle linkage and and move disconnected linkage to activate the switch on the throttle arm. With key on, gently move the linkage back, it will activate the relay to send power to the solenoid. If not, check continuity on the switch that's located on the throttle arm.
Rarely the switch or the relay are bad.
If these check out, then it's time to remove the solenoid and yes it can be done carefully without removing the hood... with a a few blankets to lean on, you can remove the complete flapper assembly with a small ratchet.

Once the the flapper assembly is away for the car, remove the solenoid.
Assuming the solenoid is not working, there is no need to unscrew the brass rod that's attached to a magnetic plunger inside, next carefully pinch back the tits holding the coil inside the case and then slide it out.
If you do unscrew the rod, be careful not to loose the rod coil spring from inside the solenoid.
Chances of the coil being bad are also minimal.
The metal plate under the male connector is the main ground for the coil and it's a poor design, as the wire from the coil just sits under it and relies on pressure to make full connectivity. In time it vibrates, arks and eventually fails to complete the circuit.

Easy but take your time Fix:  Unwind 1 wrap from the coil and be careful not to cross with the other lead going to the male terminal. The lead you are unwrapping may have to be be carefully threaded under the male terminal lead.
Next, file a small spot to the inside of the case for soldering the wire to, about 1" from outside edge. Be sure to clean and tin both the wire and the case prior to final soldering. Be sure to maintain clearance between wire and coil while reassembling.
 
Now test for continuity, if so now reassemble unit and don't forget to put the spring back in!
Then a simple battery test through it will determine if working (+ to the male terminal and - to case).
note: before pinching down the tits, check to be absolutely sure the male terminal cannot move and come in contact with the case slot.
If it does, I recommend that you trim off about 1/16" from the case slot (right side) and file the rough  edges.
I have also redone some out of the box replacements solenoids.
 
Hope this helps and keeps your older part working and on your car..
I have done this fix for mine and a couple others and works solidly.

Walt

Stingr69

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Re: Cowl Hood Solenoid Testing and Fixes
« Reply #1 on: December 07, 2020, 01:01:00 PM »
The 1114427 solenoids were also used on mid '70's C3 Corvettes.  There are a lot of good used parts out there. C3 Corvette parts prices are a lot cheaper than '69 Z/28 parts prices.  ???

KevinW

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Re: Cowl Hood Solenoid Testing and Fixes
« Reply #2 on: December 07, 2020, 02:57:11 PM »
Pics would be really helpful here, I am having trouble visualizing the steps taken.

 

anything