Banjo fittings on diesel fuel lines - tips on installation please!

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I am replacing the 20 year old flexible fuel lines from the fuel tank to my VP 2003 engine this winter (old ones had shown signs of ageing).

The connections to the engine are via banjo fittings, the flow line to the fuel lift pump and return from one of the injector pumps (I think). The new fuel lines have been supplied with identical new banjo fittings, and I have also ordered new washers which go either side. Are banjos straightforward to refit, are there any hints / tips I should be aware of with these fittings? How tight should these be??

Thanks!
 
Are the new banjos in the same orientation relative to each other as the old ones? Depending on how long / flexible the pipe is, that can be a real problem when trying to install the new! The banjo bodies need to sit fairly flat against their mating surfaces when installed. The bolts will, of course, pull them flat, but if the ends are badly misaligned, it could cause the pipe to twist. Are the banjos crimped into the ends of the pipe? On some assemblies you can swivel them a bit. On others, they are incredibly solid!

After that, it's pretty easy. Just make sure the mating surfaces are as clean as possible (you don't want grit trapped between a sealing surface and the copper. Make sure the copper washers are NEW, and don't have any bad burrs on then where they have been stamped out of the sheet from which they were made. On some cheaper ones, I sometimes have to carefully rub them on some 800-grit wet-or-dry paper on a flat surface with some WD40 or thin oil to lubricate them, just to get rid of the burr.

Can't offer any advice on tightening torque - depends on the sizes and the material it's going into, but you should feel the copper crush ever so slightly. It needs to deform to work.
 
I had a slight weep from one of my banjo's cured by replacing the copper washers with dowty seals.
 
what ever you do don't buy the volvo replacement ( usual reason). I replaced mine on a 2002, by going to a local hydraulic supplier who a made up pipe in minutes.
larger motor factors may also be able to make them up for you.
In my case there had been a change in the (current) metric fittings but my supplier sorted this out - no problem and at a great price. Also gave me several additional replacement nitrile rubber seals.
 
Copper washers and don't beef them up hard, it's easy to break the banjo bolt. Tighten until it "bites" and no further. I broke one and ended up with a homemade new one as a stopgap - 12 years ago. Still going fine.
 
Thanks all.

Bav 32 - The replacement lines have been made for me - much cheaper than official VP ones.

Avocet - interesting comment re orientation - two of the replacement pipes are short ones on the return side which connect the 3 fuel pumps together - these I did buy as VP parts. I am not sure the orientation is correct, and the short length of pipe will make twisting them to fit difficult and I suspect, perhaps not advisable. I intend to check this weekend.

Banjos on flow and return are different sizes, so should not be an issue mixing the bolts
 
Just in case any 'accidents happen' when fitting: when my excess fuel return line failed at a banjo fitting I silver soldered it back together. (Silver solder is MUCH stronger than soft solder and almost as easy to use with a good blowtorch and the right flux!) Still working perfectly after 8 years.
 
Fit new or annealed copper washers. Only ever tighten wrist tight ( ie, using the muscles in your wrist and not your arm and definitely not hanging off it!). Fuel hose generally has a service life of about five years before it hardens up. It could last much longer but the clock is ticking after five years.
 
cryan said:
Fit new or annealed copper washers. Only ever tighten wrist tight ( ie, using the muscles in your wrist and not your arm and definitely not hanging off it!). Fuel hose generally has a service life of about five years before it hardens up. It could last much longer but the clock is ticking after five years.
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The of ones I am replacing are 20 years plus !
 
cryan said:
Fit new or annealed copper washers. Only ever tighten wrist tight ( ie, using the muscles in your wrist and not your arm and definitely not hanging off it!). Fuel hose generally has a service life of about five years before it hardens up. It could last much longer but the clock is ticking after five years.
Click to expand...

Thats a nice description of tightening I hadn't heard before! I like the bit about 'wrist tight' as the bolt that goes through the banjo is hollow with holes etc which makes them rather weaker than a normal bolt that size. (And impossible to replace with a normal bolt; there's a fault that's a sod to find when someone's been tinkering with something!)
 
sailorbaz said:
The copper washers can be reused by annealing them. Just heat to cherry red holding in pliers! Use a blow torch or a gas ring, then plunge in water. Rub on 800 grade paper to remove any scale.
Sailorbaz
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This can also be good practice on new ones which are often work hardened by the stamping process during manufacture . The softer the copper the better especially when using the low torques required for banjo bolts.
 
It's worth having a good clean round the fittings before disassembling, use a spray and brush, WD40 is OK, saves muck going into the works. Always anneal the washers or use new ones.
 
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