CSV Nozzle cleaning

[RonDwyer]

Greetings all, my first post here.  I've been an accomplished mechanic on the BMW CS Coupes and other earlier models for years and have owned quite a few Benz sedans going as far as diesel engine rebuilds. 

I'm not having a lot of success opening up the nozzles on my CSV and was wondering if the syringe suggestion is to put HCL into the nozzle openings or from the back side through the inspection port.  I have some friends in the medical field who can get me a suitable syringe so understanding where to apply the acid treatment is my question.  Additionally, it would appear that 2-outlet nozzle head is press fit to the housing and it is not removable?  I don't want to break something trying to remove it and then have to call Tom Hanson tomorrow with a horror story.  After cleaning, should I be able to blow through the inspection port and hear some air going through the nozzles? 

The solenoid o-ring was completely gone so hopefully I can get one at the bearing supply house.  The Cat dealer has an incredible assortment I took advantage of when I rebuilt an antique bulldozer.  I think I'll get all the hoses replaced, then clean the injection pump accessories.  My car has had a significant laps in required maintenance so this should get it running reasonably well again. 

Many thanks in advance here.  Another upcoming project is going to be resurrection of the power steering.  I have a feeling the king pins are all gummed up from a lack of lubrication.  That sounds like a fun project...

[Benz Dr.]

The nozzle can be removed. I clamp it in a vice and then use a twisting motion to pull if off the housing. Although this doesn't always work I've been able to mix and match different units where the nozzle was open but the valve had an incurable leak.

The holes in the nozzle are very small and prone to plugging so they won't always clear out. The main thing that plugs them seems to be rust particles which are not easily dislodged by anything like carb cleaner so I guess anything is worth a try because even a rebuilt CSV is several hundred dollars.

[RonDwyer]

Thanks, I shall give the nozzle removal idea a try next weekend.  I may have discovered my steering issue, it's a new car to me and loaded with issues to sort out.  It looks like the last owner managed to replace the feed hose to the pump with a straight piece that did not have a curve in it so the hose ends up being kinked. the underbelly is really roached over from years of leaking oil and dust.  I hope San Jose Steam Cleaning is still in business!   They put them on a hoist and you get a car back as clean as new.

[stickandrudderman]

This is exactly why I bought an ultra-sonic cleaner.

[Benz Dr.]

This is exactly why I bought an ultra-sonic cleaner.

Yup, that helps out a lot. I have seen a few where even that wouldn't clear it out.

[RonDwyer]

What sort of ultra sonic cleaner do you refer to?  Something like the ones for cleaning jewelry?  How long does it need to run to usually clean these nozzles?

[stickandrudderman]

30 minutes at most and I've not had one yet that hasn't come out spotless.

[66andBlue]

What kind of solution/solvent do you use in your cleaner for a job like that?

[mdsalemi]

What kind of solution/solvent do you use in your cleaner for a job like that?

Interesting question. My ultrasonic cleaner specifically warns (you know, the old skull and crossbones with WARNING written in big bold letters) against using flammable liquids as solvents. It's a commercial unit, made by Branson for laboratory use. I've never cleaned any fuel system components in it (have not had to) but I've used some commercial degreasers...

[RonDwyer]

My good friend in the world of chemistry has pointed out that the ideal solvent for coked oil residues is methylene chloride.  This is very nasty stuff, and my experience with it so far is that it managed to dissolve the remaining residue in my nozzles a matter of seconds.  I added just enough to cover the nozzle assembly in a tilted glass spice bottle.  Better living through chemistry!

[cfm65@me.com]

Hi Gents,
What is a CSV nozzle?
Chris

[Jonny B]

The CSV - Cold start valve. This is on the side of the intake manifold. The nozzle, activated by a relay, will spray gas for a few seconds to help start the engine when cold. The nozzle can become plugged or leak, which causes a number of maladies.

If you want to learn more, there is a lot on the site. Search is your friend.

[cfm65@me.com]

TKS Jonny,
I'll see if I can find this gadget and confirm it is working according to plan.
Much appreciated.
Regards
Chris