NITROUS OXIDE ( nos / n2o ) advice forum

I have had my WON system installed for the previous couple of months and have used it twice so far mainly just setting it up. I have a trip to Santa pod next weekend, so today I took the opportunity to test the system.

My Nitrous solenoid will not open under full pressure, I have the bottle pressure at around 920psi this is because I was turning it up to 950 and just wanted to see which way to turn the switch to adjust it up it was set at 900.

If I open the bottle and then try the solenoid it wont open. If I then close the bottle and relive the pressure from the supply line it will open. Just to prove it is this I opened the bottle then closed it to fill the supply pipe with nitrous I then cracked the compression fitting on the supply line so the pressure was slowly bleeding of and I kept trying the solenoid at first it wouldn't open but once a fair amount of the pressure had been released it would open again.

I had the solenoids serviced by the wizards around 6 weeks ago and as I previously said I have only used the system twice since then.

The only thing I've changed since I last used it was the fact that the bottle heater is now set at 20 psi more!

Any one got any ideas??

That sounds very odd ??

Can you disconnect the solenoid wires and connect them directly to a battery to make sure its not a dodgy connection?

Its sounds as though there is not enough current available to open the valve against pressure. ??

Lack of current as Perry suggests is the probably cause, so check wire grade, switch ratings, connections, etc.

BTW unless you're wanting/needing the full flow of the Pulsoid, you can make it more responsive even with a lack of current, by reducing the plunger lift by turning the seat clockwise by a few degrees or as required.

I have tried the solenoid direct on the battery it makes no difference I even cut the wires I have soldered on which are 1.5mm tri rated cable should be good for about 18A with negligible resistance. I then put the coil wires directly on the battery and it still won't open under pressure.

I don't need large flow I'm only running a small amount of nitrous 25-35shot how much can I turn the seat clockwise, as in how much adjustment is there 360 degrees ? Or a lot less than one full reveloution.

I have checked the filter and its clean,checked for nitrous flow which is fine. I can't see how it's not got enough current if its direct on the battery!!

Battery is fully charged and tested and alternator is charging it fine.

Could this be a weak coil??

Hmm??
More intrigue!! You have done the OBVIOUS test then.

I'm at the Pod next Saturday with the MGB and the Slingshot. If you want I'll bring some spare pulsoids for you to try.
I have a few

Let me know. I'll be with this car in the pits somewhere.
My name is Perry

There is no such thing as a weak coil, that's an urban myth but there is such a thing as a damaged coil, although you're VERY unlikely to have that happen to one of ours.

I suggest you do the following;

1) measure the coil resistance and report back

2) Turn the seat clockwise by approx 10 degrees at a time until the Pulsoid works but don't turn it more than a total of 180 degrees.

BTW I assume it sparks when you tried it direct to the battery?

Thanks for the replys,

perry i may well take you up on that offer. Looking foward to seeing your car regardless looks like an awesome piece of kit!

Trevor i will do those things and report back. Just so i understand what im adjusting i assume that black plastic screw in the solenoid i am adjusting adjusts the height of the seat ? So by making the gap smaller between the plunger and the seat you reduce the amount of work that coil has to do under full pressure ??

Correct but make the adjustment about an hour after the pressure has been released from the Pulsoid.

I'll bung some spares in the truck anyway.
Have a closer look at the picture, look under the carb. Can you see those familiar looking pipes??

The blower kindles the fire. That plate is what makes it light up

Did you make it today??

I got only 2 test runs in. They werent quick but they were good for data logging. I only ran 10psi but it did pull 11.2 seconds on a half pedal launch with full pedal in 2nd and 3rd gears to the finish line. I need to re jet the carb this week and then next saturday if the afr is where I want it I'll go for a 10 on boost only. Then the nitrous system is coming back from the cupboard and onto the car