Testing ISC valves - with "funny" video

[fairdeal]

The recently dis-interred thread "How to Clean IAC"
where TownsendsFJR1300 described the tamper-resistant Torx screws used on some model valves
reminded me of my adventure with the YDS "operate ISC valve" Stationary Test.

I had done it a few times with my F225 (no tamper proof screws there)

https://vid.me/THB7

And one day decided to have a look at the F90.

But there, in order to "get a good look" - I had to remove some.

"Wonder why they used these?" I thought. "Whatever. On to the test!"

https://vid.me/gqr6

[pstephens46]

[QUOTE=fairdeal;129268]The recently dis-interred thread "How to Clean IAC"
where TownsendsFJR1300 described the tamper-resistant Torx screws used on some model valves
reminded me of my adventure with the YDS "operate ISC valve" Stationary Test.

I had done it a few times with my F225 (no tamper proof screws there)

https://vid.me/THB7

And one day decided to have a look at the F90.

But there, in order to "get a good look" - I had to remove some.

"Wonder why they used these?" I thought. "Whatever. On to the test!"


Seems like you drop things often. The little ball check valve for the trim/tilt?

[99yam40]

did that break of just come unscrewed?

[fairdeal]

Seems like you drop things often. The little ball check valve for the trim/tilt?

haha yeah. I hate that "plink" noise when something tiny lands.....somewhere.

[fairdeal]

did that break of just come unscrewed?

"came unscrewed" - but that was hardly a "just" situation.

The moving "plunger" rides in a "track" -
the motor moves it in & out like the leadscrew on a lathe



which means IT can't be screwed back in by itself -

it has to be held lined up with the tracks, while the motor pulls it in.

A specific motion which the YDS "test" was not designed to produce!


Fortunately for me, Boscoe had earlier posted how to "bench energize" the ISC

And with the help of an old wall wart and a capacitor, I saved it from a one-way trip to the scrap bin