4200 oilpump failure picture
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Emtee
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Pretty horrendous Harry. Aparently the reason (from what I know) is that the section between the water pump and first oil scavenge pump breaks down and so there a rust buildup. There's a drain hole to remove moisture, but this gets clogged and the rust thrives, which then causes an increasing resistance on the shaft, and so differential turning forces required between the water and oil pumping functions. The stress goes straight to the splined joint of the shaft as the weakest point. The scavenge 'rotors' are hardened steel, so you may be able to salvage these, though I have to say that one looks quite scored. What's the shaft rotor for that section look like? It's interesting that the joining face is also heavily 'rusted'. It shouldn't be. What are the other two scavange pumps like? You may struggle to find the pump bits, as most will want to sell the unit complete, but you may be able to get a used one that you can then dismantle to check and then use the bits you need.
There's no chance of a claim against Maserati I'm afraid. It's a ten year old part.
There's no chance of a claim against Maserati I'm afraid. It's a ten year old part.
conaero
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Ehhhew, thats nasty. Hearing more and more of this type of failure.
I was speaking to an indie yesterday and was told that there are tell tail signs. If you put your finger up under the pump and check for a light spray of oil and to check the drain hole as Miles states above.
I was speaking to an indie yesterday and was told that there are tell tail signs. If you put your finger up under the pump and check for a light spray of oil and to check the drain hole as Miles states above.
Parisien
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Casting fault......whether its 1yr....3yrs...5yrs...10yrs...if an indie engineer gives a reports stating the fault was there from the start why not challenge them?
I had a 993 ...the USA forum identified a wiring loom weakness due to poor quality materials....they had a recall/agreed to fix in USA ...then one in the UK/europe........car was 6/7 yrs old.....they paid up for a new part loom and a days work....what makes Maserati above the laws of the land and fit for purpose its sold to the UK public?
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I had a 993 ...the USA forum identified a wiring loom weakness due to poor quality materials....they had a recall/agreed to fix in USA ...then one in the UK/europe........car was 6/7 yrs old.....they paid up for a new part loom and a days work....what makes Maserati above the laws of the land and fit for purpose its sold to the UK public?
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Parisien
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http://www.consumeractiongroup.co.uk/forum/forumdisplay.php?57-Vehicle-retailers-and-manufacturers
Sub forum for vehicle manufacturers
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Sub forum for vehicle manufacturers
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Emtee
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Hi Harry, it would be the first instance I've heard of if the casing is the root of the problem, though I'm happy to stand corrected on that one. I'd take the view instead that the gear has seized to the casing as a result of debris entering the chamber during the moment of failure, but from a problem caused elsewhere. If you take a look at the other chambers you'll see the inner faces of the casings are very finely machined so the pump gears can rotate against them with only a very thin film of oil for lubrication from the oil ways. All moot really as you are unfortunately where you are.
The pump sits right down at the bottom of the engine, and it's a right pain to get at because of the engine shield. Proper pump removal is an engine out job, unless you do a real botch job hacking through the shield. Does your car show any sign of this? Might point towards a previous botch. Also can I ask whether there are records of a recent oil flush, or whether you yourself have carried one out? I ask as I am personally very dubious as to the benefits of this practice, and believe that if done to an old engine can actually cause harm such as this.
Thank you Parisian for your help/support.
Like I said, I have rebuilt many engines in the past, mostly for racing for many years and I have never seen this sort of problem before. I must admit that the rotor type pumps that I have worked with have been constructed with a cast iron housing (self lubricating compared to alloy!!)
Thanks again,
Harry.
Like I said, I have rebuilt many engines in the past, mostly for racing for many years and I have never seen this sort of problem before. I must admit that the rotor type pumps that I have worked with have been constructed with a cast iron housing (self lubricating compared to alloy!!)
Thanks again,
Harry.
Parisien
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Au contraire Harry.....thank you for highlighting this and being able, and committed enough to contemplate a rebuild.......respect!!!!!
So you are saying the choice of casting material AND a failure in quality control led to this failure....all with a built-in design flaw too??!!
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So you are saying the choice of casting material AND a failure in quality control led to this failure....all with a built-in design flaw too??!!
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Hi Emtee,
I have had another look at the shaft. In the picture it looks rusty, but I can assure you that there is no rust at all, it is just the colour in the photo.
Just in case people are missing the point here. I bouht this engine with the intention of buying a high mileage 4200 to put it in. I am rebuilding it at the moment and I am totally new to the 4200 engine. I don't want to get involved with 'claims' etc. I just want a reliable 4200 that will not have an oil pump failure after a rebuild. In 30+ years of building engines, I have yet to have an engine failure due to my assembly/preparation methods. I do not like the design of this pump. I will try to find a local engineering company that can design a cast iron sleeve for each of the rotors perhaps. I am not sure yet.
I am very impressed with this site and I will keep you all posted with the progress.
Many, many thanks to you all.
Regards,
Harry.
I have had another look at the shaft. In the picture it looks rusty, but I can assure you that there is no rust at all, it is just the colour in the photo.
Just in case people are missing the point here. I bouht this engine with the intention of buying a high mileage 4200 to put it in. I am rebuilding it at the moment and I am totally new to the 4200 engine. I don't want to get involved with 'claims' etc. I just want a reliable 4200 that will not have an oil pump failure after a rebuild. In 30+ years of building engines, I have yet to have an engine failure due to my assembly/preparation methods. I do not like the design of this pump. I will try to find a local engineering company that can design a cast iron sleeve for each of the rotors perhaps. I am not sure yet.
I am very impressed with this site and I will keep you all posted with the progress.
Many, many thanks to you all.
Regards,
Harry.
Emtee
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Hi Harry, Maybe give the guys at Shiltech a call. Geoff knows the pump well. He and I pondered over mine for many hours trying to figure where my low pressure was coming from. I was lucky to catch it before it failed, so it was a bottom end re-build as a precaution and new pump, but Geoff has seen these same pumps become an issue in the Ferrari 360, so he knows their foibles. He's not a spares specialist, but he does have a good range of parts on hand, so you might fall lucky in getting the bits you want without it costing an arm and a leg, otherwise David Askew and Parisien's suggestions.
All the best to get it sorted as you want.
Regards, Miles.
All the best to get it sorted as you want.
Regards, Miles.
Hi Miles thank you for your continued help and support. This engine also needs new bearings, but at least it did not run for very long to damage to the crankshaft. I think with some modifications to the pump I will eventually have peace of mind and confidence with this engine.
Regards,
Harry.
Regards,
Harry.
