Help I don't want a mouth full of gas (petrol). I'm in the process of tearing my engine apart and I need to take off the fuel lines. is there a relay for my fuel pump that I could just pull off?

 

on a differnt subject do I need to replace my head bolts when I pull of the head or can they be reused?

leave the fuel cap off when working on pipes has always worked for me.

 

"T"....

I find that if the ignition has been off for a while then the fuel pressure dissipates anyway, but you can do it by disconnecting the green fuel pump relay, which is behind the trim down to the right of the drivers feet and then turning the engine over until it either stalls or refuses to start.

thanks for your help the car sat for two days and I opened the fuel cap. there is no pressure anymore, now all I have to do is deal with those damn hose clamps........

 

 

So do I have to replace the head bolts or can I reuse them?

The vacumn in the fuel tank and the pressure in the injector rails are not the same thing. But anyway, the pressure will almost certainly have ebbed away overnight.

It is not a vacume in the fuel tank its pressure. The pump would not work very well in a vacume cos it would just suck the fuel back.

 

Aren't the 2 seporate though?

 

Cos when I too the tank off mine, petrol poured out the main fuel line, and when I then disconnect the fuel line under the bonnet, it was still pressuries and it poured out there too.

 

Stuart

Yes, it is a vacuum in the tank, we have discussed this before - that's why the filler cap has a vacuum relief valve. It's all to do with the emission control system for the fuel vapour in the tank.

I might be asking questions that have been answerew before but if it a vacum in the tank why does it blow when you open it and not suck???

 

Sureley it pressurised air, the opposite of a vacum:confused:

 

(I somehow think AndyP is going to be right on this, as his tech experience is going to be much vaster than mine!!)

When you open the cap its 100% a blow. I can feel it blow past and you can push the cap in a little after you twist it and the noise stops. Lest go and the car is pushed out.

 

Stuart

RTFM

Originally posted by AndyP

RTFM

 

I was awaiting a more tecnical explanation!!:confused:

Me too. :S

 

 

I thought he was gonna tell us the ins and outs of it all. :(

Interesting and helpful, I didn't get a mouth full of gas and I got the fuel lines off damn those things are annoying.

 

So about those head bolts? replace or reuse?

I would say replace, as i think most bolt stretch over time

 

Maybe andyP will confirm when he explains the vacum thing to us!!!!

Head bolts - up to you tbh - they are not stated as replacement items in the manual. I replaced mine but looking back I probably wouldn't have bothered... All IMO ;)

 

The tank has a VACUUM in it! This is to do with the emmisions as mentioned above. There is a carbon cannister in the front wing of the car. Basically, there is a vacuum line from the fuel tank to this carbon cannister. This sucks fuel vapour from the fuel tank, through a check valve (one way valve), passes it through the carbon cannister which reduces the hydrocarbons, then passes this into the throttle chamber to be burnt off by the engine. So can someone now please explain how the pressure in the tank could possibly be positive? A vacuum can very frequently be mis felt as a blow - your hands aren't that sensitive to air flow direction really....

 

All I did was RTFM so why couldn't anyone else??? ;)

 

HTH

 

CheerZ,

 

Andy

BTTT - I know how lazy you guyZ can be and wouldn't go to the second page of tech so wouldn't see the post I'd put 30 mins work into.....

Oh and another point - I don't really think (and can certainly understand why) AndyP would have been particularly keen on replying to the thread after the replies he got to his last post :( Come on guyZ this place isn't just a place where you can come on and demand information. If someone WANTS to post a reply they will do - responces like that get you no where ;) ASK don't DEMAND thats all.....

 

Now I may well have taken your posts the wrong way in which case I am sorry BUT thats not what the smilies indicated ;)

 

CheerZ,

 

Andy

As you could see it was past my bedtime and I couldn't be arsed to reiterate what I'd already written, had indicated in the linked manual page and was discussed with concensus on a recent post.

 

Anyway, what sort of emissions control system would spew out the emissions it was trying to contain when you open the filler cap ? ;)

Sorry andy, didnt mean to offend. I guenuinely thought it was pressure not vacum, will do a search to find out what its all about then!!;)

Cant find anything, maybe one of you could show me a link to the thread cos i dont know what youre on about.

I think it was on Stuarts car repair diary of a couple of weeks back. Towards the end we got on to the pssshh noise that he now gets when opening the tank, now that his filler neck is fixed.