Long story, but I'll condense it down... The Zero overheats for no apparent reason ? It can go for a few hundred miles and no problems, then a short 10 mile journey and she overheats, sometimes spitting coolant out from the expansion bottle all over the floor, or the temperature gauge reaches 110 degrees before the fan kicks in ?
I now carry a 2 litre bottle of water with me to top up when necessary.
So last week, after talking to countless friends, other Zero owners, and the factory I have identified 4 possible issues...
1) Got the plumbing of the expansion bottle the wrong way round ? Well in earlier blogs I had found I had plumbed it in wrong, but that is not an issue now.
2) No hole in the thermostat plate, took a look and there is one there.
3) Pressure cap not sealing properly... well the one that I got was a sample pressure cap from a supply company that GBS where looking at to supply them with caps when they ran out of stock ? Could this be the problem ? So I removed the cap and with a file "faced" off the top of the thermostat housing for a better seal a few months ago. Having returned to GBS last week, for the sake of a few pounds I purchased another cap, which they have been using now for 18 months and have had no reported issues. Fingers crossed.
4) Broken bracket on the water rail. For some unknown reason the bracket has snapped off the side of the water rail, leaving it floating in the air with just the hoses holding it in place. While at GBS I got a replacement one of these as well.
So all replaced and topped up with water.
Guess what... STILL OVERHEATING ! .... GGGRRRRRR.
Put the Zero back in the garage and locked the door !
Next day 1am
Woke up with a thought ! (wife not happy) anyway, it has just accrued to me that every time I topped up the coolant level over the passed year its just been with water, and have I diluted the antifreeze properties to the point that its not cooling efficiently ?
At the auto factors at 8am... Antifreeze purchased.
Time to drain the system, in order to reach the lowest point I've got to take the nose cone off, while doing this found another problem... The radiator fan fell off !
It is only held in place buy clipping into the radiator, but is this the reason for overheating ? anyway, a minute later its clipped back in.
Took the bottom coolant hose off the radiator and drained off. Basically the colour was clear, hardly a sign of antifreeze, just water. Hose fitted back on and topped up with 50/50 antifreeze/water.
Got the Zero warmed up, got to 98 degrees and the fan kicks in, cools it to about 95 degrees. It continues to do this for 4 cycles. Fingers crossed its seems to behaving its self !
Going to let it cool down and check for air locks, and repeat up to temperature again.
Oh the fun of owning a kitcar !
I now carry a bottle of 50/50 antifreeze/water in the car after this. Will update if it's a cure or back to the drawing board.
Back to the drawing board
Well spoke to GBS about the issue, because its frustrating not knowing the answer ?
Basically got to try different things one thing at a time to try and eliminate possible problems, so first, go for a run and get it up to temperature, then see when the gauge reads overheating (above 98) if the voltmeter also rises, to see if there is a problem with the rectifier in the alternator ?
Well got the temperature over 100 on the gauge; and the voltmeter is a steady 14v, and when driving remains at 14v. Sat idling and voltmeter drops to 13.5v. At no point did volts go over 14.2v.
OK, so in the video below, I have found what could be another issue, while sat idling, watching the temperature rise, I turned off the side lights and saw the temperature gauge drop 10 degrees, also the oil pressure gauge did something similar ?
Will have a think about this... will update soon, hopefully with a solution !
OK found the problem.... Its a ground issue, found the offending connection under the dash on the passenger side. Looks like the rivnut is loose ? Simple repair though ?