Volvo 2001 banjo bolt washer material

[Dipper]

I've had to remove a couple of fuel line banjo bolts from my Volvo 2001 in order to change my saildrive seal. I have ordered some copper sealing washers of the correct size but then wondered if that was correct as the current washers seem to be aluminium. Would copper cause a galvanic reaction? The bolt is magnetic so presumably steel but I don't at the moment know what the fittings on the fuel line are made of. I thought they were alloy but maybe not.

 

[DinghyMan]

I've had to remove a couple of fuel line banjo bolts from my Volvo 2001 in order to change my saildrive seal. I have ordered some copper sealing washers of the correct size but then wondered if that was correct as the current washers seem to be aluminium. Would copper cause a galvanic reaction? The bolt is magnetic so presumably steel but I don't at the moment know what the fittings on the fuel line are made of. I thought they were alloy but maybe not.

If they look like aluminium they are probably dowty washers which are a washer & a seal combined

 

[Dipper]

If they look like aluminium they are probably dowty washers which are a washer & a seal combined

Good point. I'd only closely examined one washer and that definitely was all metal. A washer on the other bolt had to be prised off with my fingernail and it looks like it had a rubbery seal on the inner ring but this was in bits. Presumably some of the washers had been replaced in the past. I'll see if I can source some aluminium dowty washers.

 

[penfold]

The pipe fitting and the bolt are probably steel so copper or aluminium the washer would be either cathodic or anodic to them. Dowty bonded seals are usually zinc plated steel although can be had in stainless and other materials for special purposes, although I'd be surprised if aluminium is used anywhere other than perhaps in aerospace. The advantage of bonded seals is that they are readily reusable whereas plain (copper or aluminium) washers ought to be tempered before reuse.

 

[scottie]

Def not Dowty but alloy there is a mixture of copper and alloy washers on small Volvos.
check the parts list to see which is used where I suspect thesize and softness is more important than the material
there is plenty of alloy in the fuel system

 

[Laysula]

Copper washers are ok. Probably best to anneal them before use. Dowty washers are much better though.

 

[CM74]

Soft aluminium alloy washers are used in quite a few bikes and cars for sump plugs and that sort of thing, and also on outboards so they would be fine for fuel lines. They are softer and therefore need less torque to seal properly.
Dowty washers even less so, but you need to pay attention to sizing and especially thickness with banjo bolts as if they are substantially thicker than the original washers it might stop things lining up properly. They can be re-used too!

Saying that though, I doubt you'd have a problem using new copper washers.
After all, some engines have a fair few copper/bronze/brass bits for all sorts of things (like the 1gm10 oil pipes - originally steel, but notorious for corroding from drips from the water pump above, replace with copper, problem solved!)

 

[vyv_cox]

There is no galvanic reaction in a fuel system. Both components need to be immersed in a conducting liquid, i.e. water, to generate a voltage.

 

[Dipper]

Thank you all for your input.

I did search for aluminium Dowty washers but couldn't find any for retail sale and the steel ones are much thicker than I would want. Also, they only have imperial sizes and not metric. I'll go with my copper washers for the moment.

 

[Bilgediver]

I've had to remove a couple of fuel line banjo bolts from my Volvo 2001 in order to change my saildrive seal. I have ordered some copper sealing washers of the correct size but then wondered if that was correct as the current washers seem to be aluminium. Would copper cause a galvanic reaction? The bolt is magnetic so presumably steel but I don't at the moment know what the fittings on the fuel line are made of. I thought they were alloy but maybe not.

They are sometimes supplied in a soft white metal possibly similar to lead.