leaking cold start valve

[Madmerc]

hi guys and gals wishing you all a happy new year , just over the holiday break I have found my 230sl  a little hard to start when cold so I went thru the procedure  in the technical manual and all was great .but I have a fuel  leak from the spray nozzle jet when I turn the ignition on  as I was testing it. the only thing I could think of was maybe the flow valve seat may need re seating. does any one no where I can purchase a new spray nozzle and maybe the whole csv assembly thanks

[stickandrudderman]

Strip, re-face valve with fine paste (Autosol Solvol for example) clean and re-assemble!

[Tyler S]

At one time Bosch made a rebuild kit for these (see pic). Consisted of a new plunger and seat.  I dont have a part number but MB or the classic center will be able to tell you if available. Authentic Classics stocks everything else associated with rebuilding it such as the o-rings and screws.

[RobSirg]

Reading this post and many other similar posts about a leaking CSV had me convinced that mine was leaking too - as it is running quite rich at the moment and I am having difficulty starting especially when hot.

So I followed the tech manual and did the simple test to see if it is leaking through the bleed nozzle - but it wasn't. I wanted to check if the solenoid was working but I didn't have a test light so I decided to remove the solenoid but have it still wired up to see if I could watch the plunger move up and down. In removing the solenoid I noticed the o-ring was very badly pinched and distorted so clearly that wasn't doing its job. With the fuel pump running and the car cold (hadn't started in days - I assume that is cold enough?) the plunger didn't move. It wasn't stuck as it moved quite freely with my fingers. So I guess a solenoid problem or relay fault? - electrical anyway.

Still no leak though, should I be seeing fuel flowing with the solenoid removed and the fuel pump running?

The fuel was flowing to the CSV as I managed to remove the fuel line and have someone quickly turn the ignition on (not start) whilst I covered it with a rag. it seemed to be a healthy flow.

I really wanted to remove and clean up the CSV myself as it sounds like a fun project I could tackle after reading all the posts. I also happen to have the two new O-rings as I purchased them for my project car, however, there was no physical way I could remove the air line. Can barely get a wrench on it without removing the master brake cylinder first - which I wasn't about to do. No one mentioned in the posts that it would be virtually impossible - am I missing something? Is RHD more difficult then LHD?

I put it all back and then tried to start it - it cranked for about 5-7 seconds before starting ........which seems an eternity.

Anyway I will need to take it in to the Doctor when they return from their Summer break - a little frustrating, I hate giving up when it is just one bolt or screw that holds you back.

Appreciate any tips on what I might have got wrong.

The CSV wasn't touched until 2 to 3 years ago  - I assume it has been purely decoration since then? Also makes me wonder how on earth it started when it was cold? Up until a few months ago it started quite well when cold but took a while to start when hot. Is it running so rich that it will start without the CSV? The last few months it has been slow to start hot or cold. Maybe plugs are all fouled?

Of course it drives well but lately it has been missing when on hot idle. I also had a lot of pressure build up in the tank - so I put a flexible braided cable up the vent pipe and I haven't noticed that occur since but I only drove it once. Sounds like I might have a few things going on - I will get them checked out.

Rob

[RobSirg]

I can answer one of my questions here - just had a look at some engine bay photos and I can see that a LHD engine has MUCH easier access to the CSV - I guess this is why this problem wasn't raised before.

[Madmerc]

hi rob I understand exactly where your coming from. that nut air pipe that connects to the manifold which is practicaly impossible to get to ,what I do is  leave it on and take off the 3 x  10mm bolts that connect the csv assemble out and then riggle  it up and out  you first have to disconnect the air pipe from the wrd .then sit it up on top of the inlet manifold and test it for leaks and spray.most times if its not working it is the relay . hope that helps

[RobSirg]

Thanks - that might be worth trying. I read on an earlier post to be careful not to bend the air hose so I didn't want to touch it, but I never actually looked to see what the other end of the air hose was connected to. Might look at that tomorrow.

You might be right about the relay -  I think I already have one rebuilt from my project car was thinking about swapping them anyway.

Rob

[kampala]

Rob,

Firstly, it sounds like you expected the CSV to operate with the ignition on and fuel pump running.  To clarify, the CSV only operates while the engine is cranking.   So, to test, you just remove the little 7mm access bolt on the CSV (as you did) and put a rag and crank --- if working, you will see a flood of fuel pour out.   Of course, car should be cold.      

Also, remember that the CSV is activated by the Thermo Time Switch (TTS) which goes through a relay before it connects to the CSV.   It's this Thermo Time Switch that senses the temperature and triggers the CSV.  The CSV just does what it's told.  The TTS gets its power from the starter, so it only works while cranking.  

There is a VERY good write up in the Tech Manuel under STARTING AIDS that describes this very well so I won't go to all details here.  Our great forum folks have done a superb job on putting the info for this topic into the manual.  

http://www.sl113.org/wiki/Restricted/Engine-starting-aid-tour


If you don't have fuel coming out of the access test hole, you have a few options to begin testing.

1. run a wire from positive battery and touch the CSV solenoid electrical connection --- if touched with a hot wire, it should trigger if working --- and you will hear the loud click.  Only touch for split second.  It's dangerous to test like this with 7mm access hole open as fuel can pour while you will cause a spark --- so have that bolt in.  

2.  You can find the TTS on a pod between spark plugs 2 and 3 for some engines or close to spark plug 6 for later engines (see starting aids) and ground ONE of the connections, I don't recall which connection, but it's clearly in the write-up, and when you ground this connection, the CSV will trigger.  This will tell you if the problem is before or after the Thermo Time Switch.  If it triggers, you will know the issue is with TTS or prior.  If it doesn't trigger, you will know to chase the problem with relay or CSV.  

I am only giving you a couple of points as it's all in the starting aids --- so that's why I am brief.

Also, don't assume your Thermo Time Switch is bad if all works by grounding it but it won't work when cranking.  When mine stopped working suddenly, I found that by removing the TTS and cleaning the connections completely and cleaning the wire ends completely made it all start working.  


Good luck,

[RobSirg]

Thanks,

I cant say I have a perfect understanding.

I was aware that solenoid only works when the engine is cranked.

I did crank the engine with the Solenoid removed from the CSV but still wired up and expected to see the plunger move as the engine was cold at this point.......but it didn't. The side bolt was in so I could not tell if there was any fuel flowing anywhere.

Might buy a test light tomorrow and try those tests again as you suggest.

Rob

[Tyler S]

Rob, if you test the CSV solenoid with it unscrewed from the valve remember that it gets its ground source through its body. You need to put a jumper wire from it to a good ground source or it will never work. Also get yourself a test light. This whole system can be diagnosed with one.

[RobSirg]

Yes of course Tyler,

I'm such  a dunce on electrical matters. I'm definitely buying a test light.

One last question that is still baffling me. As the seal to the solenoid was so badly crimped it could not have been sealing. Why wasn't it leaking? Or was it leaking without my knowledge? - as I guess only on a cold start when the plunger is depressed is when the leak would occur? Alternatively, if the solenoid or relay was not working then it would not work or leak?

Rob

[Tyler S]

Rob, You will prob never see an external leak as the seal in question is exposed to manifold vacuum with the engine running. This is downstream of the actual valve that the solenoid pushes on to open. If it was pinched you prob had a vacuum leak there. The cold start valve itself can still leak fuel even if the solenoid is non functional. With the solenoid removed you can use a mirror to look down the opening and you will see a + shaped brass pin. This is the actual valve that when pushed on by the energized solenoid rod, opens up. It is spring loaded to stay in the closed position but the seat can corrode or be contaminated and leak fuel. You can push on this with a wooden chop stick or something else soft to make sure its not frozen up. It can be accessed by first removing the fuel line and then the banjo fitting (see item on left in picture). The valve (brass) and spring are inside.
One last thing. The most common electrical issue with these systems seems to be the relay on the left fender well. The contacts become dirty and pitted just like our distributor points. If anything else you can remove the relay and carefully bend back the tabs to remove the cover. Then take a very fine piece of emery cloth and clean the contacts. Hope this helps.

[RobSirg]

Thanks for the great information. That all makes sense.
A friend told me that I should hear a click and even feel the solenoid move if it was working, but I couldn't feel or hear anything when I had someone start it this morning. ( it started fairly well and we shut it off without driving it). I later purchased a test light and tried it in the afternoon. It did light up but it wasn't as bright as l expected ( car started instantly btw). Maybe l don't have a CSV issue since it previously passed the leak test?

Earlier l did remove the relay - I wanted to tidy up the contacts but l was too chicken to pull those tabs back to remove the cover. The Bakelite base seems so brittle it was ready to crumble when l tried to lever off it with a small screwdriver. I might send them away for refurbishing when I get the chance.

I still can't say for certain if the CSV is working correctly - but the solenoid does have power, the fuel line has fuel, it is not leaking ........if it starts well on cold, l might just leave it as it is not easy to remove on a RHD car.

I did replace the o-ring that was pinched on the solenoid valve.

Rob

[Tyler S]

Rob, That's great you have power there. We can almost rule out the relay. You say the light was dim so there may still be some resistance on the relay contacts, but the light was prob dim because of the starter motor drawing so many amps from the battery. We can now rule out a power feed and thermal time switch problem. Next step is to check the solenoid. Take a jumper wire and connect it to battery + (Leave the Key OFF).  Now take the other end and touch it to the terminal screw on the CSV Solenoid. (with it bolted in place) You should hear a very loud click. If not its bad or frozen. If its good move onto this last check. Remove the solenoid again and push the cold start valve rod inside the valve with a chopstick or something (Key On) as previously discussed to make sure its not frozen in the closed position. If its free and fuel comes out when you push on it your system is functioning. If not disassemble and clean/repair as necessary..
  Tyler

[RobSirg]

Thanks Tyler,

I did both tests and they passed. Got the loud click (first time I heard that?). Wonder why I haven't heard it this week on cold starts when I was standing right over it? How "cold" does it have to be? I assumed if a car was left overnight it was "cold" in the morning - even during our summertime? Got a healthy shot of fuel when I depressed the valve. If it starts well tomorrow I might just leave the CSV alone and get the relays tidied up in the future.

I still have a warm starting problem - quite slow and the car is lumpy on idle. A mechanic friend of mine confirmed today that I have a vacuum leak at the throttle body which is almost certainly the cause of the lumpy idle - we also think the Acc linkage solenoid is not functioning properly - my regular mechanic had complained about that sticking in the past.

The other weird symptom I have is excessive oil consumption and the evidence of some blue smoke. We checked the plugs and changed them for the hell of it - he also adjusted the points and we changed the oil. The plugs looked fine - nice even burning with tan coloured tips. I had the head rebuilt about 5000miles ago so we cant explain the oil usage. Can the vacuum leak cause oil to be sucked in the manifold or something?

I guess I will leave the car till my regular mechanic returns in about 2 weeks and maybe read up on some posts and try not to stuff anything up. Guess the Alfa will get this years summertime driving until then.

Rob

[ctaylor738]

I've seen several cars where the solenoid would work fine when jumped from the battery, but not when the car was starting.  If you have an old worn-out starter, a marginal battery, some resistance in the wiring and relay, or a combination, the relay may not be supplying enough power to open the valve.  The way it is wired, the solenoid is at the end of the food chain.  I fixed this problem in one car by running a wire from battery + to 30 on the CSV relay, moving it up in the food chain. 

A good test would be to check the voltage at the CSV with an analog meter.

[Tyler S]

Good point Chuck. Using a DVOM with the starter motor engaged (system under load) would be the proper test. I'm still suspecting the relay on his setup since he stated the light was not very bright. (what he has to work with)
Rob, Use the search function and search for "Oil Consumption". There are good threads about Blow-by leaking valve seals and ball adjuster leaks. Even thought the head has been rebuild your valve guide oil seals could have backed off. Does it smoke more after startup or after a good rev? As for the hard start and lumpy idle when warm, yes fix that vacuum leak and dashpot. Then re-adjust your idle settings. You may have other issues such as your FIP check valves leaking down but fix the obvious/easy things first.

[RobSirg]

Thanks again guys,

I am getting it checked out electrically in the morning. I actually suspect the battery, as I recall it started better when I had it on overnight trickle charge. This morning the test light didn't light up and the car took a long time to start - clearly no power to the CSV solenoid. I should know the reason for sure tomorrow.

I will read the posts on oil consumption. Its possible my head rebuild was not so good and valve seals have loosened - or something else. I know the guy rebuilding my project car engine would have done a much better job but I didn't know him then. It might be something I live with for a while as the car doesn't get a great deal use and in 12 months time my other car will be finished. ....will this car resto ever end? .....guess not:)

update: Interesting reading on varied oil consumption figures!
I will monitor it closely now as it was not my normal mechanic who did the previous oil change and I don't think the oil he used was all that good. I also took the car on a very long drive on a hot day which including 2 spirited mountain climbs and descents. Quite possibly that led to such an abnormal oil consumption (I went from max oil level to minimum in around 3 full tanks of driving - let's say 1 tank was mountain climb, another tank on a very hot day - 100oF and the 3rd tank normal driving).

p.s - the hot day driving was unintentional - I would not do that normally. Long story - but what was meant to be an early morning country drive ended up being a city drive + country in the hottest part of the day.
Rob

[RobSirg]

It was the battery!

CSV works fine when the battery is fully charged overnight. Not the first time a car battery has caused me Electrical gremlins that were difficult to diagnose.

I still think I have a warm start issue as it takes a while to start once it has been driven and left for a few hours. I will sort out the vacuum leak first and take it from there.

Thanks again for everyone's help / suggestions.

Rob

[Tyler S]

Rob, Thats great!   Next thing to check after you fix your vacuum leak and adjust your idle settings,  is your enrichment solenoid (if you have one) on your I.P.

[RobSirg]

Thanks Tyler,

My I.P does not have solenoids (looks like it was removed). I have seen some I.P's with 2 or one but mine does not have any.

I don't believe my 1970 car has them either (Car is in bits right now)

Rob

[Tyler S]

Rob, Here is a good thread about warm and hot starting issues. http://www.sl113.org/forums/index.php?topic=22587.0 There is a factory mod (parts NLA)  that can be done to fix the problem or a momentary switch added to the circuit.