Post fuel filter change stuttering...

[missfixit70]

Not sure about that as it should be self bleeding in theory? I'd check around for any leaks or iffy looking bits of hose/piping & go back over everything you've done & make sure there's nothing leaking or drawing in air there either.

[Mctavish]

Spoke to Phil at JAL, very helpful once again...

First thing he said was that there was no need to change the filter - doh!!

He asked a mechanic to phone me which he did -'Dave' a mobile mechanic in Worcester, who talked me through things to check, and basically he thinks either the existing filter is not seated properly or the filter itself is crap, allowing air to enter the system.

He's kindly offered to send down a couple of spare filters so that I may try again, rather than use the diesel specialists down here which may cost a bit. The filters should arrive on Friday by courier.

I'm in a dilemma - the ferry is Sunday morning (did I mention that???). Do I take it to the specialists and potentially pay an arm and a leg, or do I have another go myself on Friday?

The missus is not happy, by the way...

Mctavish

[mister munkey]

Have a go friday, you'll be fine this time round & it'll be a well deserved confidence booster when it all works well - The Mrs will be impressed too!

But book it into specialists for friday afternoon or sat morning just as a back up.

Cancel when nessacary.

Better safe than sorry.

[Mctavish]

Thanks for the support.

Found 2 local suppliers that I may be able to get new filters from. Mill Auto stocks Blueprint, so I may have some luck there. Opie Oils stocks Mahle, and their website produced an equivalent Mahle filter code based on the Blueprint reference (adk82312 for info).

I can get on that tomorrow morning, try refitting, then use the afternoon appointment if necessary.

By the way, it may be worth amending the fact sheet to say to fill the new filter with diesel before refitting. Seems obvious now..!

I shall get to France with a healthy bongo and a happy wife if it kills me ...

Mctavish

[Mctavish]

Fitted (another) new filter - noticable improvement in pick up, but still not right.

She's now with the specialists for an hour of diagnosis - fingers crossed it's something easy that I've missed. I can't believe the fuel pump has decided to keel over at the same time as a fuel filter change.

She's drivable, just needs a little longer to turnover, and at junctions I can keep the revs up using the gearbox a bit more.

Why did I bother doing this job?!?!

Mctavish

[Mctavish]

Now she's properly fixed!!

Turns out that the sealing washers in place around the banjo bolt were leaking. Don't know how they sussed it, but I'm well pleased they did!

I would be most cautious against pulling out the fuel strainer in future. The engineers at the diesel specialists (Richard Bros - Redruth) said that the strainer is the last line of defence for the pump. If any crud fell down whilst the strainer is removed then that could kill your fuel pump. In short they said that I was a bit of a wally to be playing with the pump.

I've decided on a new rule for myself not to DIY any fuel pump related issues!

If you do decide to clean the fuel strainer, it may be advisable to acquire the sealing washers and replace them as a matter of course.

So pleased to now have the bongo fit for the holiday!

Bring on le fromage et le vin rouge...

Mctavish

[missfixit70]

Glad it wasn't anything serious Enjoy your trip, after the drama
I wonder how many people may have had the same issue without realising it? I must admit I've had mine off a couple of times without issue, but it does raise a possible valid point.

[teenmal]

Hi Mctavish,

Your Diesel Technician is spot on,the strainer on the injector pump should be removed and cleaned with the utmost care.I have read on this forum that some people actually remove them completely.

Take care
Mal.

[The Great Pretender]

Mine is tucked away for safe keeping in my workshop and I would need a convincing argument as to why I should refit it. :wink:

[munroman]

Just picking up on the comment about the leaking washers, copper is another material, like my favourite, Silicone, which flows under pressure , ever opened up a electrical plug and found the connections loose? That's because the copper flows.

Might some stalling issues be caused by the leak starting as the washer flows and loses sealing pressure, and possibly the 'cure' of cleaning the strainer is actually caused by the tightening up of the Banjo connection on reassembly, and nothing to do with the actual strainer itself?

[Mctavish]

I say each to their own, but why would you not have it fitted TGP?

As my man said, it's the last line of defence.

What if you inadvertently send some crud down the line during the filter change? The crud would then have an un-interrupted journey into the heart of your fuel pump.

When I removed my fuel strainer, there was some crud in it that would otherwise have entered the pump or made it to an injector.

What are the benefits to not fitting the fuel strainer? Do you get a performance boost?

I think munroman may have a point with respect to the re-tightening of the banjo assembly. Although I did mine up fairly tight, I think best course of action would be to replace them with new, they're only a few pence.

Mctavish

[The Great Pretender]

As my man said, it's the last line of defence.

What if you inadvertently send some crud down the line during the filter change? The crud would then have an un-interrupted journey into the heart of your fuel pump.

Using that argument, why is there not a filter after the oil filter then?

When I removed my fuel strainer, there was some crud in it that would otherwise have entered the pump or made it to an injector.

What was the 'crud' solids or an emulsification?

What are the benefits to not fitting the fuel strainer? Do you get a performance boost?

If it is clear, none.

I think munroman may have a point with respect to the re-tightening of the banjo assembly. Although I did mine up fairly tight, I think best course of action would be to replace them with new, they're only a few pence.

They can be reused by annealing but better replaced if any doubt as they are under negative pressure at that point.

Mctavish

[skater]

have been following this with interest as I've been having same symptoms, as discussed
in my recent topic of "stalling only when hot".

I've now had time to look a bit closer and think I get a slight fuel weepage(?)/ air intake
at the join of one of the injector fuel pipes where it attaches to the pump.

I'm thinking as this connection gets hot on a long journey it expands fractionally and said problem
occurs.

Haven't tried fixing it yet.
Ideally I'll just tighten it up and job done...

Glad you seem to have fixed yours

cheers, James

[Tripewriter]

Hi Skater, I had a leak where the pipe to one of the injectors connects to the pump, but only when cold, at normal running temperature it sealed itself and did not leak.

There are sealing washers between the coupling which the pipe attaches to and the pump these will leak if they have been disturbed at all!

[Mctavish]

James,

Your symptoms sound identical to mine.

You may find the stuttering is after high speed rather than a long run.

Your leak is most likely on the intake (mine was the sealing washers on the banjo assembly), since the pump will be pulling air through the leak but may be able to 'process' a small amount of air at higher revs (diesels are lean burn by default). As soon as you back off (leave a motorway or whatever), the pump will contain aerated fuel introduced at higher speed, but the engine then can't deal with the air at tickover rpm, causing stutters and stalls. Mine was dipping to sub 500 rpm. On one occasion, after a steep climb (high revs), she stalled as I tried to pull away again.

I took my van to the diesel specialists and agreed 1 hours worth of diagnostics. They reckoned that would be plenty of time, and found and fixed the leak. Total cost was £59, I would have paid more!

Best of luck,

Mctavish