Astra diesel fuel pump removal

Does it actually need removing? It could just be a leaking union, gasket, or a spindle seal that could be sorted in-situ.

Huw

THe problem isn't in removing the pump but refitting it and getting the timing right.

IF it's not leaking enough to be irritating then it'll pass the MOT. Ask the garage who are prepared to fix it how much they want to remove & refit it, then you can make a sensible decision about the hassle factor.

No it wont. Well it shouldn't anyway. Any fuel leaks are a fail no matter how small. Wet leak off pipes are a reason for rejection.

John

The problem is that over a period of time of driving up and down motorways, the underside of the body has a nice noticeable coating of diesel fuel!

I've been quoted by a couple of diesels specialist my area that to do the complete job including re-calibration could cost around £400 plus Vat, which means that we're then starting to get to into the realms of younger second hand equivalent vehicles.

Unfortunately the leak is from between the main body and the end block where the injector pipe's screw into.

The two sections are held together by four Torx Bolts and it would appear that the gasket between them has failed.

Although there is more than enough room for the two sections to be easily be separated in situ, apparently this is a no-no, and a job that can only be done with the pump removed and serviced on a bench.

Have you tried tightening the torx bolts?

If you take it to an injection specialist, and let them take a look, I'm pretty sure they will be able to replace the gasket in situ, in under an hour, so shouldn't be too expensive.

The bolts are pretty solid, and over tightening with the possibility of shearing or thread stripping could do a lot more harm than good, at least it's perfectly driveable and it's only the looming MoT failure which is the real problem.

I have taken it to a couple of diesel specialists and they have both told me the same thing, that the pump will have to come out.

You could try one from a scrappy.

Yep, when you take that off you reveal the actual pump, & the new gasket will potentially screw the fuelling. Plus any dirt will kill the pump.

I've thought of that, but it would take me back to exactly square one, as I will still need to obtain a sprocket extractor compact enough to do the job in the confined space, and after refitting a second hand pump from a vehicle of a similar age and redoing the timing etc, I might then find that I have a similar problem, maybe in a few months' time.

I've heard it suggested that it's only since the introduction of ultra low-sulphur diesel fuel that these type of problems have been on the increase, it allegedly destroys the 'O' rings.

This is mostly confined to Lucas [now Delphi] DPS and DPA type pumps and is mainly confined to the simple 'o' rings that seal throttle spindles where they enter the cover.

Huw

Agreed, what I meant to say was make sure they are not loose, which you already have done.

Ok, what I would do in that situation, remove the injector pipes, loosen the torx bolts, so they are about 1/4" out of the pump and pull the block back clear of the pump body. You will get a deluge of fuel at this point, as the pump body is full of fuel during normal running. allow the fuel to drain, remove the old gasket, then de-grease the joint faces as best you can. smear a little sealant into the joint, then screw it all back together, and allow to set before re-filling with fuel. Its not guaranteed to work, as you will not have good access to clean it up and make sure the sealant has gone all round the joint, but you lose nothing trying, and you may save the cost and hassle of a pump rebuild. Be careful you don't pull the block back too far, the result will be like an explosion in a spring factory! Just far enough to work on the joint.

I cant see why it needs to come out, unless it needs to be held in some sort if jig to position all the springs and plungers on reassembly.

It's no the 'o' rings that are the problem, its the cam plate and rollers that tend to disintegrate, due to the poor lubricating properties of low sulphur diesel.

There is absolutely no lubricating issue with either low sulphur or even ultra low sulphur fuel. The fuel must meet international lubricity standards. I run several 1970's and 80's diesel engines on ultra low sulphur diesel with only positive results apart from slightly lower power output.

Huw

However if I attempt as you suggest what sort of gasket will I be liable to be confronted with, do the Torx bolts have to pass through it, and where would I be able to purchase it from? The whole diesel fuel pumps business appears to be a bit like a secret society, with little or no available information.

Browsing through some American websites a while back I chanced upon one (that I can't now find) which reckoned that there were repair kits available that came complete with replacement gaskets, 'O' rings and schematic diagrams with step-by-step instructions. IIRC it cost around $16, unfortunately no similar offer appears to exist here in the UK.

When you unbolt that particular part of the pump, you are essentially dismantling the working parts of the pump (basically lots of springs and attached parts to fly/fall out). The only feasible way to reinstall everything is to have the pump body suitably angled on a work bench. Plus after being rebuilt, things like fuel delivery and timing ideally have to be checked on a test bench.

Fuel pumps aren't really that complicated, but the consequences and likely hood of getting something wrong are to great a risk.

"Moray Cuthill" wrote

Since he has to have the pump repaired or reconditioned in any event, and it is likely to be at a set price, then he has nothing to lose by giving it a go.

Huw

He will do if he ends up with a box full of pump bits that the fuel specialists have to try and reassemble into something workable.