Volvo 940 Carbon Cannister Vacuum Hoses

[haymitch]

I was wondering if anyone could answer a quick questions please? I decided to replace the vacuum hoses from the carbon cannister to the throttle body on my Volvo 940 today because the ends are splitting.

I managed to get the hoses off okay but one hose is a different size to what I was expecting. The upper hose is between 4mm - 4.5mm (this is fine ). However, the lower hose in much wider and has an 8 mm internal diameter. Based on what I researched online I expected this to be around 6mm internal diameter.

Will it matter if I fit my replacement 6mm hose instead? It seems to fit on okay but I believe this is the hose that takes excess fuel vapors into the throttle body. Will fitting a small internal width hose impair the performance of the system? Will fitting a different internal diameter replacement be a dumb thing to do? Or will I just have to be patient and wait for more hose to arrive? It's tempting to be lazy and just fit the 6mm hose but it is a tight fit.

Because it's Sunday almost everywhere is closed I notice that Halfords sell fuel hose that is of 8mm internal diameter. Would this do the job?

[Laird Scooby]

Originally Posted by haymitch

I was wondering if anyone could answer a quick questions please? I decided to replace the vacuum hoses from the carbon cannister to the throttle body on my Volvo 940 today because the ends are splitting.

I managed to get the hoses off okay but one hose is a different size to what I was expecting. The upper hose is between 4mm - 4.5mm (this is fine ). However, the lower hose in much wider and has an 8 mm internal diameter. Based on what I researched online I expected this to be around 6mm internal diameter.

Will it matter if I fit my replacement 6mm hose instead? It seems to fit on okay but I believe this is the hose that takes excess fuel vapors into the throttle body. Will fitting a small internal width hose impair the performance of the system? Will fitting a different internal diameter replacement be a dumb thing to do? Or will I just have to be patient and wait for more hose to arrive? It's tempting to be lazy and just fit the 6mm hose but it is a tight fit.

Because it's Sunday almost everywhere is closed I notice that Halfords sell fuel hose that is of 8mm internal diameter. Would this do the job?

What size are the stubs this hose of indeterminate size fits onto? If they're 6mm, use 6mm hose, if they're 8mm use 8mm hose.

BTW, Halfrauds are expensive on things like fuel hose, i see your location is now Newmarket, there used to be a good motor factors just off the market square/carpark where Exning Rd bends to the left (as you come into town) before reaching the Rookery or whatever they've renamed it. Can't remember if they're open on sundays but worth a look.

[haymitch]

Thanks for the tip Dave! Your post made me smile - it's always the simple things. I should have thought to measure the stubs I've measured the stubs and they're 8mm so it looks like I'll have to get some more hose.

I don't know of Motor Factors in Newmarket but I'll take a look.

[haymitch]

Will it be okay to leave the carbon cannister disconnected whilst I look for replacements? I don't want to be the cause of a mini-Beirut style explosion from any escaping petrol vapour!! I'm guessing that any amount of escaping vapour will be tiny?

I'm wondering whether duct taping the ends of the old hoses and then reconnecting them until the replacements arrive would be a good plan?

[Laird Scooby]

Originally Posted by haymitch

Will it be okay to leave the carbon cannister disconnected whilst I look for replacements? I don't want to be the cause of a mini-Beirut style explosion from any escaping petrol vapour!! I'm guessing that any amount of escaping vapour will be tiny?

I'm wondering whether duct taping the ends of the old hoses and then reconnecting them until the replacements arrive would be a good plan?

It will be a small amount of vapour escaping, normally this is drawn into the inlet manifold and the injectors are shortened in their duration, all under ECU control to burn off the fuel vapour so it doesn't go into the atmosphere neat.

You may be able to trim the perished ends and get a good connection, if there's enough slack in the hoses.

Just trim 1/2" or so off the persihed ends and connect, should be good enough to last until the new hoses arrive as long as they're not perished further back than this.

[haymitch]

Thanks, I've now done that

[griston64]

I bought those hoses from Skandix so might have some spare. Happy to send out but it will be tomorrow

[haymitch]

Only just saw this. The replacement hose arrived in the post today. It looks like a good match so I think I'm fine - thanks for the offer though