99 S70 AWD large fuel leak by left rear wheel

[rollin_home]

Hi,
Im coaxing a 99 S70 AWD back to life but its recently developed a rather large fuel leak pouring down like rain over the gas tank just in front of the drivers side rear wheel. This happened when the engine was idling and despite there being only a 1-2 gallons of fuel in the tank.

Is lowering the tank the only way to diagnose this situation and find out which hose is leaking ? I opened the two portals in the trunk area but couldn't see much.

Id be grateful for some words of advice or links to other posts dealing with the same issue .

Thanks

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[scot850]

There is not much on the driver's side half of the fuel tank. Based on the possible position it is most likely the return pipe from the engine to the RHS of the tank. If you can find my thread on rebuilding the rear-sub-frame on my 00 V70R there are a lot of pictures of the pipework on there and what runs where. The other possibility is the pipe from the 'ejector' on the LHS front of the tank to the RHS of the tank which goes into the fuel pump on the RHS. These can rust out due to road salt getting trapped up there.

There are a bunch of other pipes on the top pf the tank, but with only 1-2 gallons left in the tank they are less likely to be the issue, but never say never.

I would suggest you will have to drop the whole rear sub-frame and suspension to see what is going on.

Neil.

[MoVolvos]

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Get you started perhaps?
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viewtopic.php?t=60291
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Fix s70 fuel vent hose wo dropping gas tank
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[rollin_home]

omg , just had a long read thru your v70 awd sub frame thread and I can honestly say that if I have to drop the rear subframe it would be a show stopper. Before deciding what to do , I’ll borrow an inspection scope and identify where the leak is coming from but after looking at your pictures, I’d agree that it’s likely the leak is coming from the hose which goes across the top of the tank down to the driver’s side.

Your remarks about rust and corrosion definitely apply to this car, both rear torque arms are rusted thru. To remove the ends , I had to hammer the bolts out of the nylon bushing. Right side is done but even after much hitting, LH side center bolt is still stuck, time for bigger hammer. But then what , measure the original length and weld up Replacement torque rods using original ends, legal or safe?

With these two issues pending,
- dropping sub frame to fix hose leak
- two torque arms repair
It’s looking not so good for this car but I’ll continue with the diagnosis.

For reference, link to your subframe thread:

viewtopic.php?f=1&t=69287

[scot850]

By torque rods do you mean the 'kinked' rods that run from the support just forward of the rear wheel on the floor? It kills me as I may have a good set but not easy to access in a storage facility. I also found the forward mounts were only about $5 more for the whole item with the bush already fitted than buying the bush alone. If the torque rods are being replaced, I seem to recall the bush in the frame is not listed for a part number anywhere I could find.

Be aware that there are a lot of parts that are now NLA for the AWD cars especially to do with anything like fuel pipes and rear mounting bushes in the the rear subframe.

You can drop the front of the fuel tank (someone did this in a thread somewhere) just enough to see the ejector 'pump' and the fuel pump but not enough to replace either. However, it may be possible to get enough access to remove the broken pipe from the tank end and run a rubber fuel hose over the top of the tank. If I recall, the other end of the return pipe to the tank is attached to a valve on the top of the tank on the passenger side but this may also be accessible but not easily. The pipes may not be available but yo may be able to graft the end at the tank onto a new hose.

I will watch out for your updates to see if I can help further.

Neil.

[rollin_home]

I’m mistaken , the arms are called “panhard rods” or track bars, #25 in the diagram. Both rods are rusted thru. Hope to get the scope tomorrow and have a look at the leaking hose.

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[scot850]

Again I have some rusty looking but solid versions of those. This is so frustrating not having easy access to that stuff.

The bushes were available for those a few years ago, and the rod I believe was also available and came with the bushes installed.

You have made so much progress I wish you luck with the fuel leak.

Neil.

[abscate]

You know its been a Covid year when I stumbled onto this thread, went to link it to my AWD Resurrection, noted that the car has the same off Silver doors as mine, then realised....