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kaltstart relay

kaltstart relay

Author
Discussion

Alpha Omega

1,412 posts

29 months

Sunday 18th June
quotequote all
glenrobbo said:
Here you go:





Amazed it still worked after it had been full of water when I first opened it up to investigate a few years ago. You can see the tide mark on the pcb.

Mine has "5GA 08" printed in white on the green case.
The Ford No. was the same as the previous posters' relays.

I think we'd all better keep our eyes peeled for spare ones at autojumbles in future.
This problem does not arise if you fit the relay in the upright position above sea level

haydenf

Original Poster:

29 posts

75 months

Monday 19th June
quotequote all
Thanks to you all for the good comment and photo's
The contacts look simple to clean with a small diamond contact file to make a good flat contact
As for the electronics there do not seem to be much on the pc board a few transistors few resistors ,capacitors
If cleaning do not work there could be a dry joint on the solder,or a component faulty
.
Thanks again

Alpha Omega

1,412 posts

29 months

Tuesday 20th June
quotequote all
haydenf said:
Thanks to you all for the good comment and photo's
The contacts look simple to clean with a small diamond contact file to make a good flat contact
As for the electronics there do not seem to be much on the pc board a few transistors few resistors ,capacitors
If cleaning do not work there could be a dry joint on the solder,or a component faulty
.
Thanks again
Don't use a file on the contacts as it will damage them, the surfaces will be put out of line and never meet up face to face
Get hold of some very fine wet and dry paper and cut out a thin strip a touch wider than the contacts but not too wide so that it wont fit, now fold that strip in half so that you end up with a thin strip of doubled thickness paper with an abrasive surface on each side, with the contacts open insert the paper into the gap between them, now gently close the contacts onto the abrasive paper with a finger but not too tight, while applying light pressure to the contacts the paper can be pushed and pulled in and out and will clean the contacts up without putting them out of shape

Loach1

400 posts

61 months

Wednesday 21st June
quotequote all
Are you certain that the relay is at fault? All it does it squirt the cold start injector as you turn over the engine. The thermo-time switch governs whether or not it should squirt the injector, and how long to try for before giving up. Have you confirmed that you get no squirt during a cold start? If not, I would be inclined to test the thermo time switch to make sure it is working properly first since they are prone to failure.

Let me correct myself now that I've had a chance to dig deeper. The relay is actually for hot starts and is a timer relay. When 12V is applied to terminal 50, it closes the switch between 31 and 31b for a second. This completes the cold start injector circuit so it squirts for a second. Presumably this could be replaced by any timer relay that works for one second, or just use any relay and remember to not flood the engine if it won't start.

When cold starting, the thermotime switch completes the circuit beyond that first second by using a bimetallic strip that closes the contacts inside the switch. There is a coil around the strip that heats up and breaks the circuit after a short time. If the engine is warm, this will remain open and the maximum squirt time will be one second.

Here's an adjustable timer relay that would work nicely:

http://www.qualitymobilevideo.com/bu508td.html#.WU...


Edited by Loach1 on Thursday 22 June 02:27


Edited by Loach1 on Thursday 22 June 03:16