Alky Control Pump not priming but it used to work

KEVINS

Post count: 24,375
Joined
May 24, 2001
Alky Control system has been on the car for years but went to prime the system tonight and the red LED never turned Green:

Meth tank is full
It worked a month or so ago

Key On/Engine Off I hit the prime button and I can hear a high pitch hum from the pump motor but with the feed line to the nozzle disconnected nothing is coming out.
If I loosen the feed line out of the pump liquid drips out.
Fuse from the controller is good.
Unplugged/Plugged in all the connections.
I cranked up the knob to full and same thing.
Same results with engine running if this matters any.

I have a second pump that is new in box and I plugged in the wires from the existing pump into this one (no liquid lines) and it makes the same noise but doesn't pump.

Any idea where to start to figure out why it's not pumping?

Is there a "signal" that it's missing that's causing it to not pump when the Prime button is pushed?

Kevin
 
Corrosion at the pump connections?

How old is the "new" pump? The diaphragms on them don't last very long sitting dry.

I'm just spit ballin' here.........
 
I make it a point to have mine rebuilt once year, swapping in the one I sent in last year. So the one being swapped in from the shelf is only a year old.

Doesn't sound like a controller issue, which is rare. I'm assuming this is an Alky Control system?

Maybe reach out to Julio? He's very approachable.
 
I know Julio. I thought he would see this thread today/tomorrow but I can email him, too.

There is a comment in the instructions that says:

"If the pressure setting on the pump switch is set higher than the pressure developed when the test button is depressed, due to voltage/settings on the PAC, etc.. the LED will not change color and an adjustment to the pressure setting on top of the pump may be required."

Even tho the system has worked I'm wondering if this could be the issue but I'm not sure where the "pressure setting on top of the pump" is or if I should adjust it. I don't know if this comment is to simply adjust the LED light or the actual pump activation..?

ks
 
I'm also trying to remember what electrical signals are needed before the pump turns on, if any. If I push the Prime button and I hear that hum and nothing is pumping is that the indicator that the issue IS the pump?

Or is there another signal that the controller could be missing that could still make the pump not turn on even tho I here that hum at the pump?

ks
 
The pump head has a simple spring-loaded switch that closes with pressure and turns the light green, it is adjustable and so long as the switch is set correctly, and the controller is functioning correctly is a good indicator that the pump is making low pressure if the light does not turn green, but because of the variation you quoted above is not a perfect indication of a problem when hitting the test button.
Here is a possible trouble shooting process, assuming a good visual check and verification that all wiring/grounds are good. You may want to do this with water, so you are not spraying any meth around. Also, if you decide to jumper anything or direct wire anything be careful, don't short circuit anything.
Make sure the pump suction is not clogged, you could disconnect from the pump and make sure liquid flows freely out the hose connection to the pump. If good, then...
Engine not running, just battery power, I would disconnect the spray nozzle from up pipe or where ever you have it and stick it in a container.
Push the prime button and see if you get spray out of the nozzle.
Yes, jumper the maf 5 volt ref to the maf green input, and make sure you get a lot of spray. I have a liquid filled pressure gauge for measuring pressure, this would be best, but you can still get an idea without one. I also have a pressure sensor hooked to the powerlogger which is great for monitoring and trouble shooting.
No, take the outlet line without the check valve, filter, nozzle, put in container and push test, see if you get flow from the outlet with the test button, then you are either getting no liquid in the pump suction, the pump is likely bad, or you have an electrical/controller problem.
You could try running the pump straight from the battery, you will get close to full output, if you try, do this with the spray nozzle on into a container like the test jumping the maf wires. If this works then you know the pump is good, you have an electrical/controller problem.
If you are getting a small flow, it will require more trouble shooting.
 
Thanks Nigel!
Make sure the pump suction is not clogged, you could disconnect from the pump and make sure liquid flows freely out the hose connection to the pump. If good, then...
I will try this but it's going to be messy. Pump is right under the 3 gal meth tank and it's full of meth...yuck..

Engine not running, just battery power, I would disconnect the spray nozzle from up pipe or where ever you have it and stick it in a container.
Push the prime button and see if you get spray out of the nozzle.
I get nothing, just the high pitch hum from the pump.
Yes, jumper the maf 5 volt ref to the maf green input, and make sure you get a lot of spray. I have a liquid filled pressure gauge for measuring pressure, this would be best, but you can still get an idea without one. I also have a pressure sensor hooked to the powerlogger which is great for monitoring and trouble shooting.
I think this will help a bunch but I'm not sure how I have the MAF wires connected...no MAF. What color wires am I looking to jumper? It looks like there is a green wire that is connected to a MAP instead..?

You could try running the pump straight from the battery, you will get close to full output, if you try, do this with the spray nozzle on into a container like the test jumping the maf wires. If this works then you know the pump is good, you have an electrical/controller problem.
If you are getting a small flow, it will require more trouble shooting.
How would I just jumper the the pump, what pins would I use to do this? I may start here first then work backwards.
I can bench test the refurb'd one first to get an idea of what to expect then try the one on the car.

thnx
KS
 
For what it's worth:
I noticed last night that the shield/foil on the pump cable wasn't insulated correctly and kept making contact with ground and when it did a relay inside the PAC would click.
Not sure if grounding that foil and activating a relay would hurt anything internal but when it wasn't grounded the pump still didn't work..

ks
 
I think the high pitched hum is the normal sound of the pump, can't say without actually listening to it.
You can use a multimeter to verify the wires, but the factory 5 volt reference wire for the sensor supply is grey. The signal should be green. Depending on how you have it wired up, unplug the maf connector and jump the 5 volt reference grey to the signal green, don't ground it. I like using a test light for this stuff because it helps against accidental grounding. Alkycontrol sells a plug in tester that does this, but it also allows you to vary the signal.
To run the pump off the battery, you will have to come up with something. The best would be to make a test harness, PIA. This becomes a step if everything else does not work. Would be wise to do some voltage checks at the pump first. Check with the test button and check with the maf signal jumped. Depending on your install and where the wires are you would want to make something with connectors. Create a plug in for the PAC to the pump with the same type connection for a test harness from battery to the pump. Depending on how you are with wiring, this may be easy and clean, just be careful not to ground any hot wires. I would not be sure of what to jump as far as the PAC goes, so going back to the battery is the cleanest. Maybe someone else may have a better idea, but going to the battery takes all the variables out. I would do this if I thought the PAC may be bad or some wiring with regard to the PAC may be bad.
 
^ best advice. I bought Alkycontrol tester this year and was short 120psi on a 6 year old pump. It would reach 60psi with tester on full, new pump 180+psi.
 
Kevins you probably have two bad alky pumps, The Alkycontrol tester is cheaper than a new pump. I bought the tester which lead to a new pump within in 1 week of each other.
Which tester? I see one for $250 and a pump is $170..

ks
 
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