Strange Fuel Leak 323i And Some Odd Jobs To Be Done.

[e21Keith]

I've been absent from these pages for a while, playing with some of my other toys. As a result the e21 has had virtually no use, revealing a puzzling fuel leak.

The car had sat for a couple of months unused, when I started it up there was a bit of cranking as the fuel had to find its way through the pipes to the injectors, when I moved the car there was a small puddle of petrol under the fuel pump area but no sign of leaking or where it came from, I took it out for a run and no sign of the fuel leak, puzzling.

This week I went through the same process again and found the same puddle of petrol, jacked the car up, let it get up to temperature, no sign of a leak anywhere. I have no idea where it's coming from as it only seems to leak during the cranking when I start the car, not while its running.

Other Issues I've discovered after not using the car:

The valve for the heater has failed, everything moves as it should but I only get hot air, simple fix replacing the valve with a spare from my stash

The rotary heater control which directs the air up/down is seized so that needs careful dismantling before damage occurs.

I have slight play is the OSF wheel bearing, I think it's always been there as there was a discussion about it at the last MOT, I've tried adjusting it up but can't eliminate the play so I need to dismantle the hub to check everything.

Lastly the brakes are quite spongy, they have never been great, everything was new, master cylinder, pipes, callipers refurbed, properly bled. I suspect the wheel bearing has something to do with it and possibly some adjustment on the remote servo linkage

[Jeroen]

Hi Keith! Always work to be done huh?!

I've also had the occasional fuel leak, only after longer cranking when the car had been in storage for several months. After that it was all good. I jacked up the car when parked for a while again, had the mrs start the car and then I could see a tiny leak, probably becoming apparent due to some excessive pressure build up. One short piece of fuel hose and the problem was gone.

[yatisr]

I had a similar problem, albeit while the car was in regular use. I would find a small puddle of fuel beneath the fuel tank after starting the car, but once the car was moving there was no leak. The problem was traced to the fuel sender assembly O-ring. I would check this too in addition to the fuel hoses.

Yatis

[nic65]

unfortunately the quality of the current fuel hose is often bad, only use excellent quality hoses,
Sunday the engine bay of my E30 Touring flooded because a 2020 pipe broke

[e21Keith]

Thanks for the replies.

The tank is under 50% full so I'm going to discount the sender unit issue.

All the pipes were new from BMW a few years ago, but I suppose one could be leaking, there is absolutely no sign of a leak though.

[nic65]

at first my pipe leaked as soon as i started the engine, then it stopped