Cold Start Valve Repair Issues

[alchemist]

My CSV (1967 230SL) is internally leaking even after through cleaning of the brass valve and the seat. Sometimes it does close and most of the times leaks. When poking the valve with a fine ice pick, it moves freely, the solenoid works fine. Also, the 2 jets are blocked and they only sweat a little rather than spray fuel. I would like to know:
•   If the brass valve and the spring can be purchased, if so, are there any suppliers or a part No. available?
•   Can the CSV be rebuilt, if so, are there any professional shops available?
•   Is there any method for unblocking the 2 jets other than using acid? Acid reacts with the soft metal and it causes increasing the bore of the jets. The 2 jets do not seem to be an open tube because a fine pins can not go through, they must have a spring loaded valves at the end of these jets. If this is true, then, where the cleaning fluid should be injected? There is a hole beside the brass value inside the solenoid seat; it seems that this hole’s outlet is the 2 jets. Is this the hole where cleaners should injected?
•   I would appreciate any suggestions and information to get these jets open.
   

[ja17]

Make sure that the screen in the intake fitting of the unit is not clogged if you are not getting a good spray.

[jedwards]

I had much the same problems as you but did have some success in the end.

My valve and seat only needed a bit of lapping. I used toothpaste as a fine grinding paste and simply pushed and rotated the brass valve against the seat back and forward by finger pressure until I had a created a clear and even “ring” around the value's face, showing that I did have a good mating surface.  A minute or two and mine was fine.  I also stretched the spring a bit to make sure I had plenty of pressure on the seat.

The spray “head” is actually press fitted so can be carefully wiggled out with a pair of cloth covered pliers and a bit of patience. Once I got is separated I used a piece of very fine wire to clear the holes and some carbi cleaner to make sure it was spotless before carefully tapping it back in. Once it is separated you can hold it up to the light and see what's happening.
Mine has worked perfectly ever since.
Hope this helps.

[tel76]

One word of warning if you remove the spray head make sure it is refitted correctly (the orientation is correct) and the spray head is a tight fit in the housing( I used Loctite to secure it).
If the spray head comes off it will spoil your day.

[alchemist]

Thank you Joe, Jed and Tel, you taught me that the jet housing can be removed. This will make the jet cleaning much easier. I will report on the outcome once I get the valve seated and the jets open.

[alchemist]

Progress Report of CSV:
I was able to polish the CSV’s brass looking valve and its seat and it worked well, no internal leaks are detected. I also was able to take the injectors port off the CSV and tried to clean it with conventional solvents and using a thin wire. This method did not work well, one port was cleaned but the second was not. So, I bought an acid used to clean concrete floors from a hardware store, it immediately reacted with the injectors by bubbling gas and spitting black foam. This process should not be left for more than 1-2 minutes because the acid would dissolve the metal, then it should be rinsed with water. I repeated this procedure 3 times and that opened both injectors. Problems solved thanks to the wonderful experts in this forum.

[ejboyd5]

An ultrasonic cleaner such as used on jewelry would work well in this application.

[alchemist]

Good Point, Can the ultrasonic works to clean injectors? Do you have experience with the injectors cleaning?

[Cees Klumper]

Dr Benz (Dan) I think has also advocated the use of ultrasonic cleaners for injectors and CSV. I've tried this recently, on an injector for cylinder 5 that is relatively new, but since the plug was black compared to the others I thought it couldn't hurt to try my wife's jewelry ultrasonic cleaner on this injector. I also managed to open the injector with my fingernail, something Joe Alexander (JA17) said was possible. I put a thin piece of plastic to keep it open as I put it through a few cycles of cleaning. Just pulled that and another plug to see if it remedied the situation, but it appears not. Perhaps the FI pump is out of calibration though, or my wife's machine is not heavy-duty enough. So no conclusive result there. If I am not mistaken, ultrasonic cleaners are used by specialized shops to clean injectors.

[wwheeler]

Gus at Pacific Fuel says he uses ultrasonic cleaners to clean injectors. There are probably many different models and possibly many tricks of the trade.

[mbazinet]

Do we know if anyone professionally rebuilds these ? I'd like to send mine out.

[Shvegel]

I believe H and R fuel injection on long Island(New York) rebuilds them. 

[mbazinet]

yes I called them today   they quoted  $350.00   for a CSV rebuild    not sure about solenoid replacement  i told him i had a new one  and he told me he would need it.    given the rather complex pressed assembly for the jets and proper clean-out,   I am thinking I will  send mine to him.

[mbazinet]

I ended up performing  the re-lapping of the valve and its mating surface with some polishing compound, it now works properly and the engine is finally tunable !
I have chased this condition for weeks ! Very happy running engine now,   going to change the oil to get that fuel contaminated engine oil out of the crankcase !

[wwheeler]

Good job. As long as there is not significant damage to the seat or plunger and the solenoid is working, new O-rings and lapping will usually do the trick. Pretty great design.

[Tyler S]

Im sure most of you who have a "Dremmel" tool have seen the little bottle of red paste that comes with the bit kits. Its a coarse polishing compound and works great for lapping these in.

[mbazinet]

Darn  have that very same Dremel tool and the bit kit somewhere in my garage,  I  completely forgot about using it.   I ended up doing it very awkwardly by hand trying to sing the valve within the seat.   Great reminder to get organized !