Cold start valve needle

[mauro12]

Hi guys , something strange happened to me . My car with a freshly rebuilt injection pump has always suffered , even before the pump rebuilt , from an hard cold start . I decided to overhaul the csv with the help of my mechanic , we found out that the internal jets have been blocked by some sealant . We put everything back together but the car was running so rich with a huge amount of smoke and very rough. We came with the conclusion that the csv brass needle and spring are not sealing properly , there is no other explanation. I believe that even if the csv is activated only with the solenoid input , there must be always a fuel pressure coming in the pipe so if there is no proper seal , you will have a flood of fuel into your engine .
I decided to buy from the sl shop in uk a new brass needle and spring , I also bought a new strainer connection to the csv , I guess it should improve the sealing capacity .
Have you ever had this problem with needle replacement ? I haven’t find nothing in forum .
Thank you

[mauro12]

Any suggestion for me or advice ?

[rwmastel]

I decided to buy from the sl shop in uk a new brass needle and spring ... Have you ever had this problem with needle replacement ?

Are you saying you bought the needle and spring, and are now having problems replacing old with new?
Are you asking if others have had to buy new needle and spring to achieve a good internal seal in csv?

[mauro12]

I would like to know if you ever had the same problem with the needle and spring . I had a big internal leak in the csv with the old one . I’m waiting for the new parts and I will install

[rwmastel]

I now people have had external leaks, but I don't know about internal leaks that cause rich running condition.  I think that is less common, or maybe people don't know or can't find the cause and they make other lean adjustments to compensate.

[mauro12]

The main cause of rich running condition is the csv leaking internally. Is the worst because you have a flow of petrol pouring inside your engine and that’s the worst .

[mauro12]

Guys sorry , I’ve just received the new csv needle valve form the sl shop uk but I have some doubts .
I will post a picture , the old needle valve used to have a pin hole ( I guess to let the fuel pass through) on the top but this new one doesn’t have . Do you think it will work ? Thank you

[Cees Klumper]

Well it certainly looks different to me ... maybe send the photo to the supplier and ask for confirmation this is the correct item?

[mauro12]

It looks the same apart from that pin hole on the top . I’ve been told from a friend that recently lapped his old needle , that this hole has not any structural function .
I’m still waiting for the answer of the sl shop but I’ve seen the same item for sale in Germany ( sls shop ) . For this reason I guess it should work.
Do you know how the internal needle of the csv work ?

[stickandrudderman]

The standard procedure for checking for a leaking valve is to remove the small 7mm(?) plug with the engine running. If you see fuel leaking then your valve is either open (constant 12v) or leaking. A leaking valve can usually be resolved with lapping paste.

[Lorsar]

Mine leaked a little, after cleaning everything I stretched the spring a tiny bit which made for a tighter fit when closed.

[mauro12]

My needle was not sealing properly . The conical shape was not round anymore . The result was that after some cranking , the position of the needle moved and a huge fuel flow was entering in the engine . For this reason I decided to disconnect temporary the csv and wait for a new needle .
I tryed to lap the valve but no results . Maybe with the lathe you can re shape again but buying a new one is just 20 €.
This small thing is essential because is the only barrier between the fuel pipe and the intake manifold.