Oily mess... Is this a tandem pump seal failure?

Fishman

A2OC Donor
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A2 has failed its MOT on an oil leak. I've tracked it down to coming from the top right of the back of the engine. It's a bit cramped around there but I'm curious of this looks like a tandem pump seal failure.
 
I can't tell from the pictures about the oily mess, but the inner CV boot also looks like it's about to give up as it looks a bit like molybdenum grease is leaking from that too

Are you able to share any photos from above the engine? The leak looks like it's coming from somewhere on/near the top of the engine
 
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Yeah it needs a new inner CV. Its done a nice job of hurling CV grease everywhere.
The top of the engine looks ok.. the oilyness is all down the back of the engine.
 
I understand that the rocker covers on the AMF can be a bit leaky - but I'm out of my depth on that one so I am sure an expert will be along shortly
 
The MOT tester commented it was a bit dieselly too. All I can smell is oil and it looks like it's been leaking for a while because everything is filthy (between that and a split inner CV).

I also notice the heater matrix pipes seem to be soft where the oil/diesel has been present. I guess these will need replacing too.

I have ordered a cam cover gasket too. I need this car MOT'd and useable ASAP!

See the state of my undertray and how much oil dropped in under 10mins of idling.
 

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Having experienced all three of the above failures - in combination as well as an oily turbo on an AMF -

Fuel pump leak -> reach around underneath where the coolant temperature sensor is. Below this you can run your fingers under the return pipe to the coolant expansion tank and then there are some pipes taking coolant to the heater matrix. All of these pipes tend to get contaminated with diesel, resulting in black sticky stuff pooling on the underside (especially) - that ends up on your hands.

Oil coming out of EGR and then running down the back of the engine to the undertray - could be leaky EGR membrane, the oil may be coming from the turbo itself.

However, leaks in this area can also be confounded by leaking from the rocker cover - usually the right corner directly underneath the cabin air intake trumpet. You should be able to get your hand under this, and run fingertips around the edge of the rocker cover gasket to see if there is oil coming from there (as well).

My mechanics last year noticed that the engine itself seemed to sit slightly lower on the right than the left and suggested that may underlie why the oil was coming from that corner of the block. As I'd already seen something like this in another of my A2s I assumed it was normal - but I've read here yesterday that this can correlate with the right hand (passenger side) gearbox mount bushings exhibiting wear resulting in the entire engine / gearbox combo sitting tilted slightly downwards at that side. More things to fix .. what joy :)
 
NO Replace the tandem. Less work and more success. Go for a Bosch replacement tandem as they are a far better pump, remember to get a new OEM metal crush gasket with the 2 extra tracts of silicon. They will leak if there is no silicon.

Bosch tandem pump part number F009D02799
 
Here are some numbers that I'll make you think how hard the tandem works

150000 miles driven at 30mph = 5000 hours of engine running

say engine running at 2000 rpm or 120000 rph

5000 hours at 120000 rph

means the tandem has internally rotated........


600,000,000 TIMES
 
Generally the Bosch pump is not supplied with a gasket. Please confirm you have an AMF engine as the Bosch tandem is not a direct swap on the BHC or ATL diesels.
 
Bosch pump perfect then.
When my LUK pump leaked I tried a reseal kit and replaced all the rubber hoses. VERY short time afterwards it again leaked ruining a second set of hoses. Pump replaced with Bosch unit and never looked back.
 
It's a bit of a mess but hoping a three pronged attack on the EGR, gasket and pump will eliminate the worst of it.

Hopefully the turbo isn't leaking too...
Or the crank seal. Just everything is filthy, can you pressure wash an engine (with the starter and alternator bagged up)?
 
While you can pressure wash having taken precautions with the alternator protected. I prefer the brush on degreasers and gentle rinse off method. It is more controllable and easier to catch the crap coming off the car in suitable containers. You can also concentrate on an area if looking for a leak.
 
The advice from @audifan is absolutely spot on, Bosch pump plus genuine crush gasket is the only way. Also hoses will be required and possibly an engine cover gasket. Get some EGR seals too as the engine cover is only rely possible with the EGR removed.
One tip from me, I degrease with brake cleaner and a brush ?
 
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