Case study - OM651 turbo fault

[alexanderfoti]

Photo bucket have turned the pictures back on! I don't belieeeeeeve it!!

That really is a suprise!

I have seen 2 instances of this failure, just helping out friends with their cars. My mums 651 is still humming along nicely at 80K, having done nothing but normal services and a water pump early on.

Although she is now being forced to change for ULEZ in the next 12 months so off to a 205 with a petrol engine.

 

[Gazwould]

Why not a 205 with a diesel engine ?

 

[Wighty]

Why not a 205 with a diesel engine ?

I would guess because of the ULEZ banding because of her current diesel ?

 

[alexanderfoti]

I would guess because of the ULEZ banding because of her current diesel ?

She theoretically could go and get a diesel engined 205, but she does 90% town driving so a petrol makes more sense.

 

[Gazwould]

Best off Defo .

Shame , all the emissions equipment longevity spoil it .

 

[mrmb]

I am doing the same job now, just waiting for the parts to arrive, they should be here tomorrow. Would you have any tips how to bleed coolant system?

 

[Steve@Avantgarde]

Just fill it up and leave the cap off whilst running for 15 mins. Then give it a hard drive, come back, remove the lid and wait for it too cool. It will self burp its own air but these 651's have habit of really dropping the coolant level once they are stone cold following a cooling system drain.

 

[mrmb]

Thanks Steve for the tips. I will make some pictures when I will be doing this job. It doesn't seem, to be that difficult, only screws that holds the fuel filter bracket worry me the most as access to them is a little bit limited. Hopefully everything will go smooth.

 

[mrmb]

Hey Guys,

Small update on my case. I have replaced the intake manifold, I ahve few pictures etc. Air throttle body was very dirty, it had about 1cm of sludge in it. I have cleaned the mixing chamber, EGR, replaced all the seals, the fuel bracket was fine, no cracks, leaks under it. I have also put a new coolant - and for now everything is working great. I am surprised this type of error happened at just 140 xxx km

Thank you all for all advices

 

[steveq]

Hey Guys,

Small update on my case. I have replaced the intake manifold, I ahve few pictures etc. Air throttle body was very dirty, it had about 1cm of sludge in it. I have cleaned the mixing chamber, EGR, replaced all the seals, the fuel bracket was fine, no cracks, leaks under it. I have also put a new coolant - and for now everything is working great. I am surprised this type of error happened at just 140 xxx km

Thank you all for all advices

Hi mrmb,

Sounds like a big job.
What was the issue that caused you to replace the intake manifold?
It would be great to see your photos.

I may have an issue on mine -- I can hear a hissing noise on the inlet side of the engine. No fault codes (yet).

Did you also fit a new coolant pump?

 

[ajlsl600]

Uncle benz well spotted that man.!!! get this fairly often on volvo adt40 inlet manifold cracks in the only place one CANT see. boost disappears, engine makes so much row at high boost rpm its hard to hear, and feeling around that area can be a trip to burns unit , mind you the first time i had this i spent 1.5 days trying everything else, before removing inlet manifold...in de bush wid NO diagnostic kit,mk 1 eyeball n mk 2 ear....

 

[LostKiwi]

mk 1 eyeball n mk 2 ear..

Best diagnostic kit going sometimes...

 

[Uncle Benz]

Uncle benz well spotted that man.!!! get this fairly often on volvo adt40 inlet manifold cracks in the only place one CANT see. boost disappears, engine makes so much row at high boost rpm its hard to hear, and feeling around that area can be a trip to burns unit , mind you the first time i had this i spent 1.5 days trying everything else, before removing inlet manifold...in de bush wid NO diagnostic kit,mk 1 eyeball n mk 2 ear....

Can't believe the original post is nearly three years old now! It lay undisturbed for a while until Photobucket switched the pictures back on. I'm pleased it is still useful!

 

[ajlsl600]

in engineering no such thing as old info.! people STILL picking away and rediscovering brunels stuff . have a 1919 edition of C.E.F. Birds machinery handbook. it still flabbergasts me that anyone knew the stuff thats in it then! and i often refer to it. and last week i had my chainsaw play up ,would NOT idle , clean plug ,adjustments to carb settings ,air filter ect. 1.5 hr later turned out gasket between carb and barrel had been half spat out ! sucking in air. how? carb seemed tight and saw had never been opened up .but that was it .

 

[Uncle Benz]

in engineering no such thing as old info.! people STILL picking away and rediscovering brunels stuff . have a 1919 edition of C.E.F. Birds machinery handbook. it still flabbergasts me that anyone knew the stuff thats in it then! and i often refer to it. and last week i had my chainsaw play up ,would NOT idle , clean plug ,adjustments to carb settings ,air filter ect. 1.5 hr later turned out gasket between carb and barrel had been half spat out ! sucking in air. how? carb seemed tight and saw had never been opened up .but that was it .

Indeed. When I was at college many moons ago, my favourite lecturer would reach for a vacuum gauge as his first tool of choice when faced with a misbehaving engine. A surprising amount can be gleaned from observing this humble device!

 

[ajlsl600]

fortunately, most principles remain even benz still have to observe suck,squeeze,bang ,blow.. tho the kilowatt is trying to interfere with that !! and i a BIG believer in keeping it simple, for me the secret of good and long lasting design . unfortunately being overcome by the constant consumer ideal.

 

[mrmb]

The reason I have replaced the intake was an error code about flaps that cannot reach its position. I have decided to get a brand new manifold, you never know what can be wrong with it. Manifold wasn’t that dirty, I could move the flaps by hand and they did not jam, I suspect it could be a faulty sensor in the electric motor that operates the flaps. I will clean the manifold and see if I can plug to the car to check the correct operation then I would know for sure, but well, we know that there are problems with these intake manifolds so I think it is better to replace with a brand new one and forget about it, otherwise you are risking with the same job being done again

 

[Steve@Avantgarde]

fortunately, most principles remain even benz still have to observe suck,squeeze,bang ,blow.. tho the kilowatt is trying to interfere with that !! and i a BIG believer in keeping it simple, for me the secret of good and long lasting design . unfortunately being overcome by the constant consumer ideal.

Unfortunately the demand for high efficiency and lower emissions are forcing manufacturers away from good working technique and into building something as lean as possible and as lightweight as possible.

Weight for added CATs and adblue systems = fuel economy so it has to be pulled back somewhere.

 

[ajlsl600]

Unfortunately the demand for high efficiency and lower emissions are forcing manufacturers away from good working technique and into building something as lean as possible and as lightweight as possible.

Weight for added CATs and adblue systems = fuel economy so it has to be pulled back somewhere.

understand yr point steve. think you understand mine. in some cases i have a little sympathy for car makers, but NOT often and not when they impliment what i see as knee jerk reactions costing us motorists significant amounts to maintain ,i cant count the number of clogged /carbon,oil ect erg valves i have had to deal with.it if it must be there make it easy to get at ,simple to maintain and relativly ecconomic to replace, recently i relplaced one that was £900.00 complete with built in non servicable motor!! seems a get it out of warranty scheme rather than a decently engineered solution, unfortunatly these days there are many examples

 

[LostKiwi]

Very little is designed to be fixed these days. Last year I took an old amplifier for repair (bought new by me in 1978). The guy who repaired it loved working on it because it uses discrete components and everything is either available or has a modern equivalent. It cost me £150 for the repair. There were 13 separate faults he fixed.
He was saying modern stuff uses dedicated integrated circuits and once the chip goes out of production the amplifier is scrap.

Progress.