Cleaned the points and repositioned. I now have continuity when they close but still no spark? Sent from my SM-G981B using Tapatalk
The contacts should not spark much when they open if there is a capacitor across them.. Does the metering pump click when you connect 12 volts to it ? It should also eventually suck up fuel and produce a metered pulse of fuel each time. That corresponds to the pump repressurising the injector nozzle pipework in the heater so it sprays for so many rotations of the fan according to the gears, before being repressurised by the pump as the contacts open and the 12 volts is turned off on the pump. This way the air fuel ratio is held sort of constant - the faster the fan spins, the faster the fuel flows in a precise ratio.
I didn't hear the pump clicking, saying that I didn't have the fuel attached. I just assumed it would tick like my deisel heater pump, and it didn't. For a split second I thought I seen a spark but then assumed I'd imagined it. Sent from my SM-G981B using Tapatalk
The fuel pump points barely spark if at all , have you got 12v live feed to the fuel pump? The switch is on the earth side via the points
The pump should click. It will work without fuel for a fair while as it may have to self- prime sucking the air out of the fuel pipe at first.. No click with 12 volts power means pump is broken - its based on a solenoid driving a diaphragm with one way valves .
Put 12v to it and pulse an earth approximately once a second for a couple of minutes to prime it whilst the heaters running, it should fire if fuel is the only issue, have you checked the fuse in the green wire from the control box?
The diagram shows two one up by the safety switch, but mine doesn't have it. Good news, though it's working, I pulsed the negative like you said, and the fuel came through. I then stuck the original connectors on, and it carried on working. It's not very hot, though, like my deisel heater is... should it be? The exhaust blows hotter air. Sent from my SM-G981B using Tapatalk
that trick usually works , have you got the temp turned up? It takes a little while to get to full temp
I had it running for about 10 minutes. I'm just reading this, so I'm going to test it. I've also got air bubbles in the tube and a slight weep of fuel so need to sort that out. Sent from my SM-G981B using Tapatalk
Test 1 Yes, it continues to run. Test 2 No, it continues to run. Sent from my SM-G981B using Tapatalk
My heater doesn't get that hot. The exhaust from it is proper toastie, but the heat coming out the front vents is luke warm. I took the thermostat apart today to look for something obvious, but apart from two scratch marks on the printed circuit, I couldn't see anything else. Is there any way of testing it? Sent from my SM-G981B using Tapatalk
blocked vents? when mines cranked up its so hot that you can't put your hands over the dash vents and the blower is strong enough to suck up sand off the floor and shoot it up at the windscreen
As I was saying at the show the other day, if the heater internal fan motor spins too slowly, the fuel metering pump just runs slower to keep the mixture optimal, so it produces less heat. So an airflow blockage could do that, so could a motor with age weakened permanent magnets.. That PCB doesnt look like it handles any current as no burn marks , so there might be a relay or two somewhere that handles the power for the motor..
Not much change of getting another fan motor (I assume it's the one with the points you're on about) so I'm trying to rule other stuff out. Sent from my SM-G981B using Tapatalk
Look to see if the motor sees voltages up to 12 volts across it for max speed... As for magnets you may find its the same motor as eg. Bosch windscreen wipers and so a motor rebuild may be possible. It may just be needing some 3 in 1 dripped onto its sintered bearings having had all the oil roasted out of it over the years.
