Om651 not starting

[Kev555]

They are piezo injectors uncle benz but have been changed to the solonoid type at some point as they have leak off pipes if my info is correct that i have gained on them. Sorry no pictures as im at work. This evening i can post a picture if you need one

 

[Uncle Benz]

Piezo have leak off pipes too. You'd better show us I think

 

[ajlsl600]

I'm old school I'm afraid. Any symptoms pertaining to an individual cylinder lead me to starting with the basics. Single cylinder faults will be caused by lack of compression, valve leakage, injector fault or valve timing. I would test in that order. The valve timing thing is very unlikely, but some modern camshafts are made of a shaft with the lobes pressed on. I have seen slipped lobes before. Very unlikely, but in my trade you never rule anything out until you have checked.

i recently came accross a cam made up of lobes pressed onto a shaft.wot a crap idea..just something else to fail.

 

[ajlsl600]

Hi Botus no way to get in around an om651 with any sort of heating equipment without doing more harm than good. I have been a mechanic in the past so i have a fairly accurate hand as what pressure to apply safely although your always tempted to apply a little more lol. WD40 over a number of days has always got me out of tight spots before including glow plugs. its always having to rush a job that gets you me into problems. time is one thing i do have but seriously short on patients

yr right there.slowly,carefully = less spent. often a little time away at another job and returning ,surprisingly solves the problem, but if you need car to work,this can be an inconvenient approach

 

[Kev555]

Ok uncle benz i will post a photo this eve. Thought i read somewhere that mercedes changed a lot of these injectors at the start to solenoid type. Cant remember what the original type of piezo injector that mercedes supplied?. Am i correct in this assumption?

 

[Kev555]

yr right there.slowly,carefully = less spent. often a little time away at another job and returning ,surprisingly solves the problem, but if you need car to work,this can be an inconvenient approach

Threads were ok on all but one glow plug Ajls but i suppose pays to be careful. Glad rust didnt penetrate down into threads or it would have been really awkward. And as ive got a second run around i could afford to take my time thankfully

 

[ajlsl600]

i stand to be corrected ,sounds a bit like .uncle benz earlier. choking on exhaust gas as for clyinder thats worst, which cylinder is closest to a mouthful of fouled egr exhaust gas,or is egr centraly mounted.? i have normaly found that when replacing injectors of correct make /type they will run ok on previous setting stored in the ecu. there is benifit in performance/efficiency in coding, but that most times it will run ok. .this is NOT benz experience ,CAT HITACHI and others. is there a way to block egr ? on this motor ,even if only to prove the point and can a deffective egr contribute to the origional black death synario especially if dodgy injectors or oiling involved. just asking.

 

[ajlsl600]

Threads were ok on all but one glow plug Ajls but i suppose pays to be careful. Glad rust didnt penetrate down into threads or it would have been really awkward. And as ive got a second run around i could afford to take my time thankfully

steady,she goes you WILL get there.. then if like me ,if/when it happens again you will probrably forgotten what resolved the issue

 

[Uncle Benz]

There was a recall for injectors to be replaced on many. This involved adding a return line and a replacement ecu as well. I believe the new injectors are also piezo type though.

 

[Kev555]

steady,she goes you WILL get there.. then if like me ,if/when it happens again you will probrably forgotten what resolved the issue

Lol i will never forget this van and prob all for the wrong reasons at the minute

 

[Kev555]

 

[Kev555]

 

[Kev555]

Leaving injectors back in again to get checked as i think like uncle benz and others that excessive exhaust fumes and vehicle being choked is down to either injectors or EGR although EGR hasnt thrown up a fault code since the initial start up.

 

[Kev555]

Just twigged on now uncle benz what i think you were trying to get across. Do you mean the whole injector is a different type between piezo and solenoid or just the guts of it

 

[Kev555]

Update 1 injector faulty in the new batch from quick test, guy was very apologetic upfront if it was his fault but he has to investigate injector to see theres no contamination from my fitting or fuel. i am quite confident as i am very aware of cleanliness around fuel parts but not sure how clean the fuel is. Other 3 injectors are on a 2 hr test to show any faults.

 

[Uncle Benz]

These are piezo injectors. As far as I am aware these type cannot be reconditioned successfully.

 

[Kev555]

I dont know Uncle benz. i will enquire tomorrow on the legality of that. but the diesel specialist is a fully fledged operation with over 30 years experience. I will have to ask that question carefully if i want to remain on the right side of him. lol
I do know know that i didnt get my old injectors back the first time around
Fingers crossed for good news tomorrow. worse case scenario, if contaminents from the fuel have messed up a full set of injectors this could be a very expensive lesson.

 

[Uncle Benz]

For the last twenty years I have entrusted Automarine Diesel in Brighton with testing/reconditioning of injectors and pumps. In that time I have received nothing but good service and advice. They told me not to waste time and money on reconditioned piezo injectors. They can source new cheaply via Eastern Europe, but the lead time is long. Mercedes offer "exchange" injectors for a considerable saving on "new". What you actually get are new, but they take your old ones out of circulation.

 

[Kev555]

I have only used this guy twice or three times as ive only lived in this neck of the woods for 16 years but service has been excellent and everybodys word on him the same. This is the first time ive had to question him is this part new or reconditioned as all the other pumps and injectors ive left in were recondition jobs. Im sure i will hear the answer they are brand new injectors tomorrow when i ask. Thats interesting info you posted uncle benz. Just to add as i forgot, This new injector which is faulty regardless of whos fault it is has to be replaced not reconditioned or fixed so i suppose that maybe goes someway to answering if the injectors are new or reconditioned

 

[Kev555]

i stand to be corrected ,sounds a bit like .uncle benz earlier. choking on exhaust gas as for clyinder thats worst, which cylinder is closest to a mouthful of fouled egr exhaust gas,or is egr centraly mounted.? i have normaly found that when replacing injectors of correct make /type they will run ok on previous setting stored in the ecu. there is benifit in performance/efficiency in coding, but that most times it will run ok. .this is NOT benz experience ,CAT HITACHI and others. is there a way to block egr ? on this motor ,even if only to prove the point and can a deffective egr contribute to the origional black death synario especially if dodgy injectors or oiling involved. just asking.

On a off topic note ajls you mentioned CAT and Hitachi which i heard recently talking to a Cat technician that most Cat diggers have been coming with DPF,s fitted and technician said their main line of repairs and call outs are DPF related now. Same goes for Case Diggers. these DPF,s and EGR,s i doubt are going to give headaches for years to come.