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TNT ANDY
11-08-2009, 07:00
Hi everyone - has anyone done this before.

I have just installed an adaptronic ecu which I am able to set the ECU to prime my fuel pump as soon as I turn on the ignition. Now since doing this the carb does not suffer from evapouration as the bowl is full as soon as the ignition is turned on, does not have to wait until the engine is cranked to activate the pump and starts very quickly and easily.

My car has never started so quickly and it would not be too difficult to put a timer relay to run along side the exiting fuel pump relay or even replace it completely with relatively low cost if you are running standard AEI units?

We see a lot of CJ1's churning over for 5 seconds or so until the bowl is full again.

Any comments?
Big Steve - Raider
11-08-2009, 08:24
Sounds simple but effective like all clever mods??
paul b
11-08-2009, 08:38
mmmmm, brains ticking here to....LOL.
Big Steve - Raider
11-08-2009, 08:49
Just to confirm you're not running a set of spangly injectors etc etc with this ECU are you?? It's still a standard set up (Carb) & you're just controlling the fuel pump with the ECU?

It's interesting to think that all these hot start problems are actually waiting for the fuel pump to fill the carb bowl & all that cranking is a waste of time?

Hand on a minute, what is this ECU actually doing for you then cheif?? :scratch:
Andrew Cooke
11-08-2009, 08:55
when I still had the C1J I always primed the fuel system before starting, I don't recall any hot start problems.
Spooky
11-08-2009, 09:41
The bowl is pretty brimmed up most times anyways isn't it ?

When you remove the entire carb, what pours out ? :D

Its not like theres a little amount of fuel present.
Os8472
11-08-2009, 17:08
Interesting, my Emerald primes the fuel pump before starting aswell, does the adpatronic also cuts the fuel pump the second the engine stops turning? like when you crash so the fuel doesn't keep coming
Mart
11-08-2009, 17:27
The float chamber never completely empties anyway, hence there'll always be enough fuel present to fire up the engine.

Even if it was totally bone dry, for whatever reason, it should only take a crank or 3 of the engine to fill it regardless.
Rob@Backyardracing
11-08-2009, 18:33
Interesting, my Emerald primes the fuel pump before starting aswell, does the adpatronic also cuts the fuel pump the second the engine stops turning? like when you crash so the fuel doesn't keep coming

Yep will do....
Brigsy
11-08-2009, 18:35
Back in the day when i had the pump rigged up to the ign, the engine still started poor when hot, possibly heat soak causing the fuel to evaporate from the inlet?
TNT ANDY
12-08-2009, 06:43
Just to confirm you're not running a set of spangly injectors etc etc with this ECU are you?? It's still a standard set up (Carb) & you're just controlling the fuel pump with the ECU?

It's interesting to think that all these hot start problems are actually waiting for the fuel pump to fill the carb bowl & all that cranking is a waste of time?

Hand on a minute, what is this ECU actually doing for you then cheif?? :scratch:

Yo Stevie - Still on a carb ATM with a plan to go EFI by easter next year. Yes just controling the fuel pump with the ECU ATM. I am wasted spark also but I don't think that this will have improved initial starting that much. Hopefully I'll be able to mock something up with Hammond over national day and see if this priming relay idea will work.

I'm sure there may be 1 or 2 members who have done this to a fashion by doing away with the origional fuel pump relay and made it so that once the ignition is turned on the pump runs regardless of whether the engine runs or not.
TNT ANDY
12-08-2009, 06:45
Interesting, my Emerald primes the fuel pump before starting aswell, does the adpatronic also cuts the fuel pump the second the engine stops turning? like when you crash so the fuel doesn't keep coming

Yup

Although I have not crashed it.

Although it looks like I have.

:smokin:
TNT ANDY
12-08-2009, 06:46
Back in the day when i had the pump rigged up to the ign, the engine still started poor when hot, possibly heat soak causing the fuel to evaporate from the inlet?

I'm talking ****e then.

Next thread peoples.

:coffee:
markey b
12-08-2009, 13:34
lol, my pump is on a switch off the ignition, havn't really noticed much diff, it starts even with pump switched off from fuel in the bowl
tobester
12-08-2009, 14:50
lol, my pump is on a switch off the ignition, havn't really noticed much diff, it starts even with pump switched off from fuel in the bowl

I have a similar setup (separate switch on dash), confuses the crap out of me when the engine dies after about 10 seconds after starting, until I realise I have forgotten to switch the pump on, again.:ashamed: