ain in diesel fuel line

[saleen 192]

ok wize kids question for you good or bad damage or not?

renault diesel fuel line to filter then to pump the line to pump you can see air bubbles in the line every 15 secs or so sometimes a small number or a large number of bubbles ,
question will this damage anything ? injectors, pump seals, filter, as car is running fine,

 

[renchero]

car is running fine for now. bound to get worse at a very inconvenient time.

 

[saleen 192]

yes that wat i feel but renault have said nothing is wrong plugged their scanner in all ok i said this is a mechanical fault not an electrical issue so your scanner will not pick it up untill say air in the injector effects it's perfermance and throws a code , car already had one injector replaced under warentiy,

 

[Will]

I've not played with diesels much, but it could be a very small leak in the feed from the tank to the pump which is sucking air in. We've got a little petrol go kart and that was doing something similar where the little clear plastic pipes had gone hard and weren't sealing. I could see the bubbles in the pipe. Fitting new pipes sorted it.

I found this in the web...
Air in diesel fuel line
4 Answers. Pinhole leaks in the low-pressure lines from the tank to the pump can cause this - the pump sucks in air through the hole instead of fuel from the tank. Check the condition of all the fuel lines, and the connections between rubber flexis and solid lines. Check any seals on the filter for the same reason.

 

[saleen 192]

thanks for info, wonder if it will damage anything????????????????????????
all fuel lines are ridged type no rubber ones , if pipe from tank was damaged wouldnt you expect fuel leak with air getting in? and fuel line from filter to pump was replaced with factory renault hose filter and filter hosing was replaced last year from renault as well the mystery continues

 

[Will]

Yeah, you might think there should be a visible leak somewhere really. I guess the only way could be to pressurise the tank somehow and look for any drips from the fuel lines?

 

[TransAmDan]

Is the pump at the engine it tank end.
Sone diesels the pump it at the engine so would be sucking from the tank, a pin hole air could be sucked in.
If the pump is in the tank then the leak may be in the tank, pipes in there and air can get in the tank to stop a vacuum occurring.

 

[saleen 192]

the pump is bolted to side of engine ,
you have the tank then fuel ine to filter hosing on driverside inner wing then fuel line to pump,
we will properly next wekend take fuel line of filter that goes to pump and put into a container of fuel and see if we get air bubbles if not then filter or line to tank is at fault,

 

[renchero]

i had this once after changing a filter. was a faulty batch of filters. 3 spot welds on the o ring sealing face stopping the ring from sealing

 

[TransAmDan]

Good point. You recently changed the filter, perhaps it's a bad one?

 

[Jumbot]

Leaks like this are a pig to find, I recently put another engine in only to have the starting thwarted by an O ring on the new filter, it was too small as in thin and letting air in, put the old O ring back and no problems