Super fuel causing problems?

[Guinney1971]

(01 Sep 2021, 12:48)Rich H Wrote:

(31 Aug 2021, 22:55)Guinney1971 Wrote: I remember Malc Lomas years ago saying that he put BP Ultimate in his car, and basically it 'cleaned'
the fuel and dumped crap in the injectors making it run like a bag of poo.

That was me. Way back in 2007

I'm sure Malc had the same issue, because when he said about it you recalled it happening to your car.

[Rissy]

So just a continuation of developments/progress of this thread.

My problem is still apparent. It's improved a bit i think, but the problem seems to come in when at a steady state speed on the motorway. Anything above 52mph it seems. I can accelerate up no problem, but it seems when leaving your speed/pedal at any position at speed for more than around 30 secs, it then develops jittering, as if struggling to get enough go juice or something. If i lift off and reapply, it seems to reset, and gives me another 30 secs before returning, or subsequently, if i press harder, it also goes away. Over the weekend just gone, I learned to continually change my pedal position just to maintain speed. That was my new driving habit on the motorways. Anything below 52mph, the car seems fine.

My intention now is to do as suggested, and reassess fuel pressure and most likely raise this up using shims.

As a reminder, I've now changed the following:

Fuel pump
Inline fuel filter
pickup hose in the tank

I'm still running Super fuel (99 octane).

I've got a petrol weep from my top copper washer on the top banjo fitting on the top of the inline fuel filter. Just couldn't get it to seal properly using ordinary copper washers, but lived with it over the weekend. It was only ever so slight. I've bought some copper crush washers to try instead, to see if that helps. Still awaitnig arrival of these. Anyone else ever tried copper crush washers for this banjo fitting?

[Justwatching]

(16 Sep 2021, 18:03)Rissy Wrote: I've got a petrol weep from my top copper washer on the top banjo fitting on the top of the inline fuel filter.  Just couldn't get it to seal properly using  ordinary copper washers, but lived with it over the weekend.  It was only ever so slight.  I've bought some copper crush washers to try instead, to see if that helps.  Still awaitnig arrival of these.  Anyone else ever tried copper crush washers for this banjo fitting?

I had the same problem, and yes, crush washers helped a lot. I'm still not sure if the leak is entirely gone. There's no mist or drip that I can find, yet last time I went under the surface above the filter looked slightly glazed/damp. Hopefully just residue from the previous leak.

I think it was caused by poor filter manufacture. The upper sealing surface did not look perfectly flat, and if I rested a washer on top, I could see a small gap part way round.

[Rissy]

(17 Sep 2021, 10:08)Justwatching Wrote: I had the same problem, and yes, crush washers helped a lot. I'm still not sure if the leak is entirely gone. There's no mist or drip that I can find, yet last time I went under the surface above the filter looked slightly glazed/damp. Hopefully just residue from the previous leak.

I think it was caused by poor filter manufacture. The upper sealing surface did not look perfectly flat, and if I rested a washer on top, I could see a small gap part way round.

OK, good to know. They're in the post and on their way. So when they arrive, I intend to get covered in petrol AGAIN! Weird, as I never had an issue 6 yrs ago the last time I changed the filter. Still using the same fuel filter as I did last time (Mahle KL-204), which are easily sourced all over. This particular one doesn't have a pressed in connection nut, instead it's the better design of a nut shaped threaded housing. Superior for easier sealing (discounting the issue I've found this time!?).

Thanks Rory.

[Rich Hanlon]

I'm convinced this is due to the bolt bottoming out before it's fully squished the coppers up. I had to double up on washers and it sealed just fine.

[Rissy]

Just another quick update to this thread. Sorry for the gap in time since last post. I know a couple of you are still interested and following...

I've finally changed out my copper washers on my leaking/weeping banjo bolt for the fuel filter. This time I've used copper crush wahers. Still required quite a bit of squeezing down with the spanner, but it sealed completely this time. Somewhat easier than using normal copper washers, so recommend to others who may have similar sealing issues.

Next step for me again, is get back to the fuel pressure stuff. Not sure when I'll get around to this, but i'll update once I do. Again, for those interested and still following.

I hear others may be suspicious of different running characteristics since introducing a fuel type different from their normal juice. So maybe not just me.

[Chris Williams]

Quote:Somewhat easier than using normal copper washers, so recommend to others who may have similar sealing issues

Do you mind posting a link to what you bought?

[Rissy]

Yeah, certainly.

This is what I bought. For this application, you want M12 size.

https://www.ebay.co.uk/itm/133359099449

[Chris Williams]

Without checking would they be the same size as the sump plug washer?.....

[Rissy]

(11 Oct 2021, 17:27)Chris Williams Wrote: Without checking would they be the same size as the sump plug washer?.....

Without checking myself, I couldn't say.  Sorry.  I've never had a problem with the sump plug sealing though, and the amount of torque you need for the sump plug probably advises you that a copper crush washer is probably not required (overkill?), maybe even not advised in this application in case you're tempted to over torque the bolt to crush the washer down...

The fuel filter is different.  It has to withstand 5+ bar of fuel pressure.

For the engine oil sump plug, have you tried a rubber ringed sump washer?  The type which have a rubber inner diameter ring as part of the main metal washer?  They're quite good, and often supplied for Honda's.

[Chris Williams]

Quote:For the engine oil sump plug, have you tried a rubber ringed sump washer?  The type which have a rubber inner diameter ring as part of the main metal washer?  They're quite good, and often supplied for Honda's.

I have seen these yes, however my Renault engine'd car and brother in laws similar one all use the same crush washer as our D's so I have a bag of them!
Chris

[Rissy]

Curiosity prompted me to figure out the name of the washers I was on about for sealing the oil sump. I'm still not certain of the size required for that application, but they're called "Dowty Washers". Here's a link to what I'm on about. Readily available all over.

https://www.ebay.co.uk/itm/203030292061?...%3A2334524

[Rissy]

M16 for the sump plug apparently. So whatever you wish to use to seal it, it needs to be 16mm diameter.

[Rissy]

Right. So I've just received back my fuel pressure gauge back from the calibrators. Just so you know, I've got a major branded fuel pressure kit (Item No. 5301) made by Bergen (now US Pro it seems) and not a cheaper chinese alternative one might find on ebay.
I wanted to have my gauge checked for accuracy before I used it to measure my fuel pressure again (even though I did this in June, I've more recently changed things like pump and filter etc, so want to check what it's doing now compared to then) with the view to increasing my fuel pressure at the regulator.
I'm glad I did.
It turns out that my gauge was reading consistently too low, meaning I've actually got higher fuel pressure than appreciated since when I first used this kit, brand new, in Feb 2017, with Nick T's guidance at the time (thanks Nick). Comparing the displayed pressure to actual pressure still tells me my fuel pressure *was* still on the low side, so it's still worth reassessing and probably increasing. My gauge was reading around an almost consistent 0.25 bar negative deviation from real. That's more than my appreciation of even the expected accuracy of this gauge as advertised by many sources of this gauge kit.

I guess that this is just a heads up appreciation for people to proceed carefully doing such an exercise, because you may not be in full appreciation of correctness if your kit is not accurate.

I'm hoping this weekend to do the status quo check again. Maybe more, depending on time.

[Guinney1971]

Interesting stuff, especially following on from our chat when you popped over last weekend.