1995 855T PCT nipple opening

Klausc · Post by **Klausc** » 21 Aug 2015, 10:47

While cleaning my PCT, I have a question regarding the small vacuum line nipple. Is it supposed to be the same diameter all the way through? I first inserted a 3d nail, smaller than the passage, and it went all the way through to the large center hole. I then tried a larger nail with the same diameter as the small nipple hole, and the nail stopped with just the tip poking through to the large center hole.

EDIT: the nipple inside diameter is 3/32 until the very end where it is 1/16. According to my drill bit sizes.

Is this very small hole supposed to be like that? Or is it supposed to be the same diameter all the way through? The small hole is quite a restriction. Even a round toothpick doesn't go very far.

Thanks...

I hate the EGR system by the way. The carbon sticks to everything!

Post by **rspi** » 21 Aug 2015, 12:03

Yes it has a smaller hole inside.

Klausc · Post by **Klausc** » 21 Aug 2015, 12:44

Thank you. I will put it back in and hope that the pressure in the crankcase goes down. You would think that a new PVC system would eliminate the glove giving me a 5 finger salute. It hasn't yet.

This engine is soooo dirty from neglect, who knows what is causing the crank pressure to be so high. I guess I need to do a compression test?

Klausc · Post by **Klausc** » 21 Aug 2015, 13:46

Cleaning out the bore on the little PCT nipple did it! It passed the glove test! With a small note: When the AC compressor kicked in, the glove did a light hearted wave like the Queen of England and then slowly went back down.

Thanks!

Post by **jreed** » 21 Aug 2015, 18:07

I was curious about the inside workings of the PTC valve, so I got a couple at the junkyard a while back and took one of them apart. I wrote up the adventure here:
https://www.matthewsvolvosite.com/forums ... hp?t=68898

: Cross section of PTC showing small hole in copper sidewall; PTC 06 small vacuum port hole.jpg (91.79 KiB) Viewed 661 times

Enjoy!