38dgas Carb with electric fuel pump issue
Discussion
This may be just mine but worth checking to be on the safe side.
I have just fitted a facet gold pro fuel pump and King filter regulator setting the fuel pressure to 4 psi. When checking for leaks I found that the brass inlet valve on the carb leaked only a tiny amount but any fuel leak it not good. I thought this must be a faulty carb so replaced it with my spare only to find it was exactly the same. My car is an early one so does not have a return so maybe with a return they will be ok
I have now silver soldered in the brass inlet into the carb and the leak has gone.
Like I have said this may be just related the the carbs that don't have a return or it could also be that I have two faulty carbs. But this is definatley worth checking just for piece of mind and only takes a minute or two with a bit of tissue.
Chris
I have just fitted a facet gold pro fuel pump and King filter regulator setting the fuel pressure to 4 psi. When checking for leaks I found that the brass inlet valve on the carb leaked only a tiny amount but any fuel leak it not good. I thought this must be a faulty carb so replaced it with my spare only to find it was exactly the same. My car is an early one so does not have a return so maybe with a return they will be ok
I have now silver soldered in the brass inlet into the carb and the leak has gone.
Like I have said this may be just related the the carbs that don't have a return or it could also be that I have two faulty carbs. But this is definatley worth checking just for piece of mind and only takes a minute or two with a bit of tissue.
Chris
May not be relevant but I do remember in my memory that there was an issue with the Essex engines where the brass inlet pipe could come loose
and spray fuel all over the interior of the engine bay, and quite a few Capris/Scimitars etc were lost to fires.
The advice at the time was to araldite it in and pin it so it couldn't come loose again....
and spray fuel all over the interior of the engine bay, and quite a few Capris/Scimitars etc were lost to fires.
The advice at the time was to araldite it in and pin it so it couldn't come loose again....
Yep, that brass inlet pipe coming loose is what I remember.
I agree with above, solder will bond to the brass, but not to the alloy casting (as far as I know).
I think that's why the advice was to araldite it after cleaning.
But who knows, if it's a slight leak, solder may be enough to seal it, even if it doesn't fully bond.
I reckon you should keep a careful eye on it.
I agree with above, solder will bond to the brass, but not to the alloy casting (as far as I know).
I think that's why the advice was to araldite it after cleaning.
But who knows, if it's a slight leak, solder may be enough to seal it, even if it doesn't fully bond.
I reckon you should keep a careful eye on it.
Alot of 3000M & Scimitar's had underbonnet fires ..... or worse, due to this 38 DGAS issue.
The bonnet on my 3000S was a freebee I got from Tony Abrams, came from a new car that sustained a bonnet fire, which was extinguished, but not before destroying centre of bonnet above carb. I have always gone the Aeroquip route, removing brass inlet & tapping a female thread, so a male to male adaptor can be fitted to accept a -6 hose.
Cheers Ian
The bonnet on my 3000S was a freebee I got from Tony Abrams, came from a new car that sustained a bonnet fire, which was extinguished, but not before destroying centre of bonnet above carb. I have always gone the Aeroquip route, removing brass inlet & tapping a female thread, so a male to male adaptor can be fitted to accept a -6 hose.
Cheers Ian
plasticpig72 said:
Chris,
why and what is the advantage of an electric pump
Alan
There are a few advantages to an electric pump the main ones are as follows.why and what is the advantage of an electric pump
Alan
1 better flow of fuel to the carb epecially under hard acceleration on tuned engines.
2 if the car is left for a while an electric pump will fill the carb fuel chamber up quickly without having to turn the engine over for ages.
3 slight power increase from not having the fuel pump running directly from the cam pulley and less heat transfer from the engine block/alloy pump to the fuel.
4 less chance of getting vapour locks in the fuel line system aiding hot starts.
Hope that helps
Chris
hi chris,
I have a 3000S and also a Lotus Elan Sprint.
On the Lotus i have fitted a Bulb hand primer inline like used on outboard moters. So when the car has stood for a while i fill the twin dellortos by squeezing the Bulb primer. Which does not effect the mechanical pump. The safety of the mechanical pump is it stops pumping when the engine stops.
An Outboard Bulb primer can be fitted inline to fill the Weber dgas when the car has stood not being used for a while.
To help stop vapour lock the fuel line near engine can be insulated using heat insulation for this purpose.
IMHO when the engine stops there must be a device to stop electic pump operating.
Needless to say i will be fitting a Bulb primer very soon to my 3000S like i have to my Lotus with great sucess
Alan
I have a 3000S and also a Lotus Elan Sprint.
On the Lotus i have fitted a Bulb hand primer inline like used on outboard moters. So when the car has stood for a while i fill the twin dellortos by squeezing the Bulb primer. Which does not effect the mechanical pump. The safety of the mechanical pump is it stops pumping when the engine stops.
An Outboard Bulb primer can be fitted inline to fill the Weber dgas when the car has stood not being used for a while.
To help stop vapour lock the fuel line near engine can be insulated using heat insulation for this purpose.
IMHO when the engine stops there must be a device to stop electic pump operating.
Needless to say i will be fitting a Bulb primer very soon to my 3000S like i have to my Lotus with great sucess
Alan
phillpot said:
Electric pump on my Taimar when I bought it, I've added an inertia switch
Now that is a good idea, i like that. Could change my way of thinking when fitting electric pumpsAlan
There are many ways to make an electric fuel pump safe in the event of a crash. The inertia switch is one. You can also use an oil pressure switch so while there is oil pressure the pump runs if the engine stops it also stops the the fuel pump. You can also do the same using the alternator. The last two though do need a priming switch but this can be a simple a rocker switch you just press for a few seconds.
Chris
Chris
Last W/E i just drove back home from Brest to Lorient in Brittany in very heavy rain 130 kms in 1hr 15mins and my 3000S was running nice and cool. Nobody overtook me and swmbo just said when it rains harder i just drive faster
She was very busy bailing the water out and muttering some French words (for info she is french)
Alan
She was very busy bailing the water out and muttering some French words (for info she is french)Alan
I use a simple diode/relay cut-out circuit that was kindly supplied to me by Adrian. I'm sure if you ask him he would share it with you. Dead simple, easy to install and dirt cheap - all the things I like. I have a Jag push button starter switch to prime my carbs tucked under the dash.
I have a Rover inertia switch discreetly mounted on the bulkhead to shut off the fuel supply plus an isolator for the pump which works as a primer or to turn off if I'm working on the car with the ignition on. All works well.
Bear in mind the inertia switch needs to be mounted the right way round not at 90 degrees.
Bear in mind the inertia switch needs to be mounted the right way round not at 90 degrees.
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