Indycam

Did you get the new parts on ?
Did it fix the problem ?

NeilW

No, and don't know. I couldn't get the old switch off the pump. Using a modified 36mm socket and with the pump body in a vice I seemed to be putting a lot of torque through the switch without it moving. Didn't seem right as tightening torque is supposed to be 26Nm/19ftlb. Also, the socket was beginning to slip on the switch as the switch isn't a true hex but rather 6 flat sides separated by non-flattened sections. If that makes sense. I'm passing the pump to my local garage tomorrow to see if they have any better luck. If I'm being paranoid it's because neither component is particularly cheap.

Will hopefully update tomorrow.

Cheers,

Neil

Indycam

You will have a junk pressure switch left over when this is done ?
If so could you cut open the old switch and show me / us all the guts of the thing ?

NeilW

I'll see what I can do.

david@st ives

I had the same problem.

I followed all the usual bleeding advice, changed the pressure switch and seal, still the problem was still there.
I exhausted every avenue, and thought there was only one option left and that was to do a continuity test on all the wiring.

I eventually traced it down to a broken wire from the pressure switch, it was broken about 6 ins from the switch itself.

One thing you will notice when you do find the problem, is that the pump will boost to a higher pressure, when i joined my wires the pump ran on for an extra 15 seconds, although you think you have full boost you have not whilst the lights and horn are showing.

What you have is an emergency state with just enough boost to stop you getting into more trouble after your problem developed.

My advice would be to sart at the pump and switch and do a continuity test on every wire.

I will have a look at my motor and tell you what wire it was.

david@st ives

Found the old post

https://rennlist.com/forums/964-foru...nd-buzzer.html

NeilW

Very interesting, thanks David. So, the brown wire had corroded within the wiring loom? From the outside my wires are all still wrapped in the original nylon/bandage with no sign of damage.

So, brown sounds like an earth wire; was it heading toward the grounding point on the left-hand (from the front) wing?

Cheers,

Neil

david@st ives

Mine were still wrapped also, i dont know where the wire headed , i spotted the wire a couple of feet away, never got to the earthing point.

NeilW

OK, problem solved. It must have been the switch as swapping that has nailed it.

At first I thought the fault was still there as the lights stayed on with the ignition and didn't go out until I actually started the engine. I'm guessing they always did that?

The local garage who removed the old switch had some fun. Firstly it snapped, separating from the threaded section. They then had to apply heat and use an extractor tool to remove the remainder. Luckily, no damage to the pump, but it makes me feel better about not being able to get it out over the weekend. Perhaps they eventually corrode in place due to a reaction between the two metals, which might be why they have an anodised finish when new.

I could probably do with bleeding the bomb/pdas valves again as I'm back to about 40 seconds from discharged with a 5/6 second burst after 3 strong presses of the brake pedal. I ran out of light tonight so I'll re-bleed later.

Thanks again for all your ideas, experience and guidance.

Cheers,

Neil