OK, I'm reading this instructional essay: https://www.volvoclub.org.uk/faq/Fue...eplacement.htm

In the section where he discusses removing the quick connector, there's no indication of how far forward the sleeve should be expected to move in order to disengage from the tube. Then, he says to push the fitting (tube) forward as well, but it's difficult to understand how the tube itself could move toward the top of the sending unit if it is a snug and secure fit.

 

Just grab the sleeve and push, then and yank the pipe, it will come loose, it is not hard, just do it! Some things are hard to explain, this happened to be real easy once you are doing it... This one is hard to screw up.

 

What you say makes sense - push the sleeve and pull the pipe. But that isn't what the instructions said, so I was confused. Thank you!

 

Update: Replaced the fuel pump, car starts up fine, but...idle is weird, so I pop the hood and what do I see? Gas literally pouring out from around the fuel pressure regulator. I pull, think "OK, replace the o-ring". So I replace the o ring. No joy. I call my Volvo mechanic to see if he has a fuel pressure regulator, but in the course of the conversation he sounds dubious that it is the FPR, like he'd never heard of one behaving in this way. But he did say you should be able to blow through it in either direction. So I attached a section of clean tubing to the return side, but can neither blow nor suck air through it. Has anybody here ever seen this kind of thing? I really don't believe the rail is cracked; I'm pretty sure the fuel I see leaking is blowing through the o-ring.

 

Is the gas coming from the fuel line or the vacuum line

 

I just replaced mine on my 740 . After 373K miles it was shot. Cheap investment and most auto parts stors carry them or can get them in a day.

 

From around the o-ring on the fuel pressure regulator, best I can tell.

 

Cheaper than exploding in flames on the highway, at any price.
Weird thing is you can find them from $15 to over $150.
Go figure.

 

the FPR has 3 connecions. fuel goes in from the fuel injector rail, it goes out to the fuel return hose, and there's a vacuum connection used to modulate the fuel pressure according to the manifold vacuum.

so, by 'o-ring', I presume you mean the inlet connection between the FPR and the fuel rail ...

 

Yep and I bought the $50 one.

 

Yes. Unless there is a component in the fuel delivery system that tells the pump to turn off and on depending on the pressure, my working assumption is that the pump is pushing fuel to this point, and the FPR has failed in a way that leaves it essentially blocked, so the pressure builds and fuel blows past the o ring.

 

the fuel pump is on as long as the engine is turning over. excess pressure is released by the FPR to be sent back to the gas tank.

 

That is as I thought; which apparently means this FPR has failed in a spectacularly dangerous way, spewing gas all over the engine block. I'm having a hard time understanding how my Volvo mechanic - who has been strictly a Volvo mechanic for several decades - seemed dubious about it, as if he had never seen this happen before.

 

Well, draw your own conclusion and get a new mechanic if you have a choice. Better yet get knowledgeable about your Volvo and avoid shops as much as possible: you'll get a lot of satisfaction and save a ton of $; having an old Volvo is a good car to own and learn on--plenty of info and help on forums, internet, etc.

 

No thanks; my mechanic is just fine. I haven't found anyone on the internet describing this behavior (gas shooting out from around the o-ring) on a bad FPR either. Besides, yesterday, when I took the part by his shop, he went and pulled one off the shelf that he had salvaged form his bone yard, and just gave it to me. Car cranks and runs fine now.

As for learning to work on them myself, I've been a Volvo owner since 1982, and have been working on them since that time. I'm here now because I wanted to find tips/things to avoid regarding replacing the in-tank fuel pump, which I've now accomplished thanks in part to the info I picked up here. Thanks everybody. It was actually easier than I anticipated. I did have to go back and read the finer details about putting the face-plate back on. It really will not go with the seal mounted on it; the seal has to be put on the tank first and all matching faces lubed a bit (I used Vaseline) before sliding it in place.

Onward to brakes and A/C!

 

Does anybody know if the fuel filter for this car is different than one for a Bosch system?
The listings on some websites indicate no; others suggest otherwise, using language like "Excl. Regina system"
I wasn't going to mess with it because it looked quite new. However, upon discovering rust in the fuel line I decided to pull it.
There was quite a bit of rust in the forward end of the filter. So I'm now pulling the fuel line and rail for TLC as well.

 

I confused here as the only way I know how to "discover" rust in the fuel line is to disconnect it and inspect it. Same with the filter where you would need to cut it open to inspect for contaminates. If you are talking about surface rust on the filter and fuel line then I can understand but not inside. So how did you look inside the lines.

 

Disconnecting the lines from the fittings, I looked into the ends with a strong light and I see rust.
The fuel filter has been disconnected from the car. It is simple to look inside and see rust. Not rust on the surface, rust inside the filter.
Disconnecting the fuel pressure regulator from the rail, I see rust inside the rail using a strong light.

 

if the input side of the fuel filter is clogged with rust, then odds are, there's a lot more where that came from in your gas tank. your in tank pump and pickup sock probably aren't real happy, either.

 

If the rust is loose debris then they need to be smaller then the filter media. Also I would conclude that the problem is with rust in the fuel tank. Pull the in tank pump and see what you get. If that's the problem you'll need to flush the total fuel system and hope the injectors aren't contaminated.