help with a diesel leak prob

caveman_si · Post by **caveman_si** » 25 Jun 2004, 20:50

HI guys just posting this in here for some more help since i knew a few of you cit drivers know a thing or 2 about diesels.
The car is a 405 1.9td so the same engine (just different shell and no lhm ) as some of the cit cars
im having more fun with leaking fuel still.
Ive just changed all the injector leakof piping (due to them crumbling apart) Bar the piece connnecting the last injector to the fuel pump cos it looks in good condition. Ive bled the system as described in the haynes but ive noticed a problem. There seems to be fuel leaking from primer bulb. Or to be more precise once the bulb becomes firm and you do an extra couple of squeezes and stop there is a high pitched wineing (similar to making ballons squeal when u let them down) and also there appears to be a little fuel leaking from the fuel tank side connector of the primer bulb. The only connector holding that end of the bulb on to he pipe work that ican see looks like a circlip type of jobby.
So is that normal? have i done some thing wrong in which case is it expensive?
good job the missus isnt here at the mo she hates the smell of diesel cheers in advance guys
simon

JohnD · Post by **JohnD** » 25 Jun 2004, 23:25

Could be that the bulb has perished and has developed a hole. I thought mine had and having got the replacement, found it was a false alarm. I think GSF supplied it.

jeremy · Post by **jeremy** » 26 Jun 2004, 13:20

These cars have no separate fuel lift pump, it being a stage of the injector pump. This means that all the pipework from the pump to the tank is under slight vacuum and when leaks develop fuel generally doesn't escape but air gets in.
the fact that you are getting diesel fuel coming out of the bulb / supply pipe connection suggests that this connection is leaking and admitting air generally. It is common experience that the hoses deteriorate with age and many of the connections aren't quite as good as when they were new. A new screw type clip on theis joint may seal it properly.
The noise- I've never taken one of these priming bulbs to bits but it must have some form if valve in it. I expect the valves seal quite well for diesel but not as well for air - so some air in the bulb, compressed, leaks out through valve - noise?
Jeremy

JohnD · Post by **JohnD** » 26 Jun 2004, 14:32

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by jeremy</i>
The noise- I've never taken one of these priming bulbs to bits but it must have some form if valve in it.
Jeremy
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
There's a one-way valve in one end, therefore it's important that it's fitted the right way round.

rotodiesel · Post by **rotodiesel** » 26 Jun 2004, 23:14

The noise you describe is the transfer pressure relief valve blowing off in the fuel pump. This is absolutely normal when the input is pressurised as you describe.
As other contributors have said, there must be no air leaks anywhere in the fuel feed or return lines - and this includes the primer bulb. Replace this if necessary; it contains non-return valves.