PTC Question

jzmuda · Post by **jzmuda** » 12 Jan 2009, 11:31

Ok,

I've been working on my PVC system, and per the warnings of many, I wanted to make sure my PTC valve was clean. I have pulled it out of the accordian tube (I know, it is going to be hard to put back in), and it wasn't really that dirty. I did spend some time making sure it was extra clean (see pics below).

My question is the following:

What part of this is a valve. I have looked everywhere and I see no valve mechanism. I can look straight through it. Sucking or blowing on the VAC connection doesn't seem to do anything either. I don't want to put this thing back in without understanding how it works and making sure it does function properly. Can anyone help me out by explaining how this part functions?

Thanks,

Jay

Post by **MadeInJapan** » 12 Jan 2009, 16:11

My understanding is that as it warms up, the temperature causes that piece that is made of copper to close (could be as simple as it expanding to shut the hole- I don't know. Anyway, it is referred to as a valve because of it's properties to close things off w/ a temperature difference.

jzmuda · Post by **jzmuda** » 12 Jan 2009, 16:28

Thanks for adding some information.

Being a mechanical engineer by day (car mechanic by night), I am sure that the hole could not open/close from thermal expansion. I wonder if part of my valve is missing. Does anyone else have a picture of this valve (one known to work).

Thanks,

Jay

Post by **MadeInJapan** » 12 Jan 2009, 18:11

Aren't there 2 parts...one like a nipple coming out of the side?

Bikerdoug · Post by **Bikerdoug** » 01 Apr 2011, 14:12

My 1st Posting - this site is worth it's weight in gold. These threads have literally saved me at least a couple of grand on my wife's S70, and I'm going to contribute. I've gotten to the point where if I can't do the repair myself, I print out the pics and threads on the repair in question, and carry them to my regular mechanic (My "Indy"...took me a while to figure out that meant "independent mechanic" to you Metric guys and no uncapitalized reference to the Indy 500).

I'm in the process of doing the PVC system and just finished cleaning out the PTC system, and came across your post and this one, which should answer your question. Here ya go, Bro --
http://www.volvoclub.org.uk/faq/EngineF ... #PTCNipple

As an aside, I just took the whole thing out, which made it easier to pull everything out and clean it. As the other posts say, it was extremely clogged up - to the extent that I had to more or less scrape and pick out the crud to get enough volume for the spray solvent to start working on it. And for those who are interested, a .38/.357 caliber cleaning bristle brush fits just perfectly - in that system and in a whole lot of others on the S70 Turbo...

Ride to Live,
-bd

Bikerdoug · Post by **Bikerdoug** » 01 Apr 2011, 14:17

Sorry, forgot to mention that I had found that the tubing coming from the PTC device was also either completely clogged or almost so. Had to use small copper wiring with solvent to ream out the smaller tube, and of course the gun cleaning kit to clean the larger one. Don't forget to check those as well when you clean the PTC.