Noisy Main Fuel Pump?

[Laird Scooby]

Originally Posted by Steve 940

That's fantastic Dave, should be really helpful.

Great tip about pulling fuses, hadn't even thought of that as a possible, seems Haynes have 'disconnect battery' before virtually any job these days, but bearing in mind working on fuel tank I wasn't going to risk it!!

Think I'll also hotglue some thin rubber around my pliers, don't need them to slip on hoseclip and spark, unlikely I suppose, but don't really fancy being BBQ'd.

Will get seats up and measure hoses through the access panel so new clips are on hand. Also will be able to see the condition of hoses, if any might need replacing then I can get hose and joiners as required.

Great to hear the Airtex ships with hose as well, will hopefully be a simple swop.

Found a supposedly genuine tank outlet gasket on eBay, but coming from Lithuania apparently so could be a while.

Yes, the Bosch one was more expensive, but overall looks as though both will come under the price of Bosch pump from UK suppliers so thought I might as well. Probably get HMRC hitting me for taxes, but hey ho😀

Oh, fire extinguisher also ordered !!! 😀

Cheers
Steve

You almost certainly won't need pliers Steve, for anything!

I can tell you the bore of the two main connections on the tank, 8mm (return) and 12mm (feed) but unsure on the OD of the hoses. If any need replacing, it's better to buy long lengths of hoses and replace the entire length, if it's perished one end then the other end will also have perished. The main feed hose (12mm bore) is the only one that needs the tank to be removed as far as i remember, the return hose has a nearby accessible hard line it connects to, the feed hose hard line is more or less above the tank though. The other end of the feed hard line is a few inches before the main in-line pump and that also has a 12mm rubber section in between.

As for the tank seal, your local Volvo dealer should have them on the shelf for about £11 - easier to pick one up from there than wait months for the one from Lithuania to not turn up! Check their feedback, if it's the seller i'm thinking of then they have a lot of negative feedback for non-delivery.

If you specified FedEx delivery on the more expensive option, that is usually with Import Duties paid so should come direct to your door, bypassing HMRC because you've already paid the duty.

[Steve 940]

Once again Dave much appreciated, I’ll get some 8 & 12mm R9 fuel hose then.
Cheers
Steve

[Forrest]

Might be worth a read of the thread from when I did my in-tank pump last year. Many helpful tips from members on here and I tried to document my experience soon afterwards while it was fresh in my mind. That one went very well.

https://www.volvoforums.org.uk/showthread.php?t=312783

I did my main pump and filter a year or two before doing the in-tank pump. Whilst notionally an easier job it went wrong every step of the way. I neglected the tips about releasing the pressure in the system and got fuel in my eye. It stings like hell! I also managed to break the rigid plastic hose the FAQ tells you not to break.

https://www.volvoforums.org.uk/showthread.php?t=287217

Good luck!

[Steve 940]

Hi Forrest,
Many thanks for that information, most appreciated.
Work today so will go through those posts this evening.
Yes, I seem to get jobs that either go as hoped, or as you say others, where it goes wrong the moment you start.
Cheers
Steve

[Steve 940]

Right, new fuel tank seal gasket picked up today from Brookhouse, so seems I am now fully armed with everything I need to replace the in tank pump.

Can't put it off much long as noise is driving me mad, project for the weekend I think.

Newbie question, so apologies, I have been keeping tank topped up to hopefully aid the noisy main pump, do I need the tank to be say down to 3/4 or 1/2 full before pulling sender / pump assembly??

New main pump and filter we're fitted when bought around 6-7 weeks ago, I have new ones just in case, should I renew them at the same time or just keep as spares??

If I need to replace filter, Forrest gave good info to be aware of stored fuel pressure, don't really want an eye full, but Haynes just says clamp hoses, not something I would want to do. Is the best way just to remove pump fuse when idling till it stalls??

Just have a niggling fear that doing that, will cause something else to bugger up!!

Cheers
Steve

[Volvo_Utrecht]

Less than 1/2 full is OK, more than 1/2 full will cause you to lose fuel.

Also I use a tiny bit of Vaseline on the rubber seal. Makes it easy to slide the tank unit in.

[Laird Scooby]

Originally Posted by Steve 940

Right, new fuel tank seal gasket picked up today from Brookhouse, so seems I am now fully armed with everything I need to replace the in tank pump.

Can't put it off much long as noise is driving me mad, project for the weekend I think.

Newbie question, so apologies, I have been keeping tank topped up to hopefully aid the noisy main pump, do I need the tank to be say down to 3/4 or 1/2 full before pulling sender / pump assembly??

New main pump and filter we're fitted when bought around 6-7 weeks ago, I have new ones just in case, should I renew them at the same time or just keep as spares??

If I need to replace filter, Forrest gave good info to be aware of stored fuel pressure, don't really want an eye full, but Haynes just says clamp hoses, not something I would want to do. Is the best way just to remove pump fuse when idling till it stalls??

Just have a niggling fear that doing that, will cause something else to bugger up!!

Cheers
Steve

If i know in advance that i need to work on the fuel system Steve, i get the car on ramps or axle stands so it doesn't need to be started then leave it overnight for the fuel lines to depressurise. Also what Haynes haven't taken into account is the fact most of the fuel lines that will be pressurised are hard nylon lines so clamping isn't an option - not without damaging the lines anyway!

As already stated by someone else (Volvo Utrecht?) you need the tank at or below 1/2 full before removing the sender/in-tank pump unit. If in doubt, get the back end up on ramps so the remaining fuel flows to the front end of the tank. Vaseline or silicone grease is useful to help the new seal slide in but only a little - retighten the lock ring a month or two after doing the job or it will leak, even with a new seal.

[Forrest]

I had the tank fairly full when I replaced my in-tank pump. I reasoned this was safer. The less room there is in the tank for air the less potential it has to explode should you accidentally strike a spark; which, of course, you really want to avoid doing.

The potential for an eyeful of fuel comes from dismantling the high pressure side of the main fuel pump underneath the car. There shouldn’t be high pressure at the fuel sender in the tank. There is a check valve on the main fuel pump which retains pressure at the rail once the engine is turned off. Three methods are suggested in the FAQ for depressurising the system.

Pull the fuel pump fuse while engine is running, engine stops with no fuel pressure left in line.
Alternative 1: pull the fuses for the fuel pumps and crank the engine.
Alternative 2: attach a vacuum pump to the FPR vacuum fitting and apply vacuum.

Where you really do need to clamp the fuel line is if you remove the filter and main pump under the car while the fuel sender is still connected in the tank. Fuel will syphon out of the tank if you don’t. You won’t have this problem if you work on the main pump while you’ve got the fuel line disconnected at the sender. However, you will then be changing a lot of things at once which will make any troubleshooting harder.

[Steve 940]

Thanks so much for responses from everyone, really helpful.

Seems I might need to do a few miles before attempting this, or I will probably syphon it out as I use it as a daily so only have the weekend to attempt this. Good to hear leaving overnight will depressurise fuel lines, seems as though the Haynes manual just copies and pastes incorrect information.

Oh well, needs must, time to bite the bullet, and I'm sure sure I will end up either posting the outcome or in desparation😀👍

[Rversteeg]

A how-to with pictures:
https://www.skandix.de/en/documents/...-tank/3000438/
Not a complicated job.