OM602 non turbo engine fails after a while when warm
OM602 non turbo engine fails after a while when warm
Hi
Hope somebody can point me in the right direction. I have started getting trouble with my Hymer Mercedes camping car. It have the OM602 5 cylinder 2.9 non-turbo engine.
The engine seems to be in good condition. The car have a low mileage for it age. It have run about 130.000 kilometers (80.000 miles). It does not have any particular noises, except for one of the hyrdaulic valve lifters from time to time ticks. The engine is very easy to start and runs just fine until it have been driven for about 40 km (25 miles), then it starts to "misfire" and loses power and will after a couple of minutes fail to run. If I wait for about 20 minutes, when the engine have become colder again, it will start and run just fine until the same situation repeats itself.
The engine is not overheating. The temprature is normal, maybe at the lower end of the scale. There is no indication of blown head gasket, oil level is correct and the oil is just changed, the coolant water level is fine.
Before last summer i removed the fuel tank and cleaned. At the same time both fuel filters were changed and fuel hoses were inspected and the worn out ones were changed. After this procedure the car were used on a vacation last year where we drove 3000km (1900 miles) after this cleaning procedure.
I have also run a diesel purge with the Liqui Moly Diesel purge (as many found on youtube). The content of the circulated fluid was quite clean and the treatment did not change engine behavior noticeable.
The only thing i found remarkable was that the return diesel hose had an surface temprature at about 50-60 degrees celsius (120-140 degrees Fahrenheit) and the container was quite hot as well. I do not know if this is normal, but the engine have two kind of heating 'gadgets' between the pre-dieselfilter and the main diesel filter. One that seems to take heat from the engine block and one Bosch gadget (looks like a icehockey puck - Bosch part number 1 455 520 072 Typ 1457 001 KBA 90251). I'm not sure if the diesel fuel temprature is normal or if that could be the reason for my problem.
I have also thought of having breather problems in the fuel tank, but I also get the same situation when driving without the fuel cap on the fuel tank.
So, if anyone can give me some ideas of what this problem can be or what to troubleshoot - it would be much appreciated
Just guessing really- but the symptoms may be indicating injector and or pre-chamber issues. These may exhibit after the engine is well and truly at operating range under load. A cracked injector housing is likely to be obvious from the get go.
Pull injectors and check for spray pattern and pop pressures.
Get a bore scope and poke this down the injector hole while injectors are out- remove glow plugs first. Check these too while they are out. Use the bore scope to check visually the pre-chamber insides. If one or more of your injectors are washing, pre-chamber failure may be imminent.
Also check that the pre-chambers are properly seated. Though if any aren't, this will be obvious to the ear even at cold- plus you'll notice bubbles at the base of the injector. My 662 is doing this right now. I suspect that the injector and collar nut is not as well tensioned as it should be.
Perform compression tests first, through glow plug holes. Best to do this twice, once cold, once warm.
When the engine begins to play up after a short run (not at the point where it refuses to run), loosen injector lines and see if there is appreciable difference between each pot.
Other possibilities include but are not limited to hydraulic lifter failure (keeping one or more valves open once it gets warm- the lifter is too hard and is locked up), cracked piston (the engine will be breathing heavily- compression test will confirm).
If any or all of the above indicate nothing unusual or wrong, then go to the IP. This may have to be pulled and bench tested. Or find another IP and insert that to see if any change is beneficial.
I'd be guessing 1. injector issues, 2. pre-chamber issues.
HTH
Cheers steu
(05-23-2017, 03:46 PM)Hello!I have some questions: How many km have you driven since the problem accured, is the intank strainer changed?s123 Hi
Hope somebody can point me in the right direction. I have started getting trouble with my Hymer Mercedes camping car. It have the OM602 5 cylinder 2.9 non-turbo engine.
The engine seems to be in good condition. The car have a low mileage for it age. It have run about 130.000 kilometers (80.000 miles). It does not have any particular noises, except for one of the hyrdaulic valve lifters from time to time ticks. The engine is very easy to start and runs just fine until it have been driven for about 40 km (25 miles), then it starts to "misfire" and loses power and will after a couple of minutes fail to run. If I wait for about 20 minutes, when the engine have become colder again, it will start and run just fine until the same situation repeats itself.
The engine is not overheating. The temprature is normal, maybe at the lower end of the scale. There is no indication of blown head gasket, oil level is correct and the oil is just changed, the coolant water level is fine.
Before last summer i removed the fuel tank and cleaned. At the same time both fuel filters were changed and fuel hoses were inspected and the worn out ones were changed. After this procedure the car were used on a vacation last year where we drove 3000km (1900 miles) after this cleaning procedure.
I have also run a diesel purge with the Liqui Moly Diesel purge (as many found on youtube). The content of the circulated fluid was quite clean and the treatment did not change engine behavior noticeable.
The only thing i found remarkable was that the return diesel hose had an surface temprature at about 50-60 degrees celsius (120-140 degrees Fahrenheit) and the container was quite hot as well. I do not know if this is normal, but the engine have two kind of heating 'gadgets' between the pre-dieselfilter and the main diesel filter. One that seems to take heat from the engine block and one Bosch gadget (looks like a icehockey puck - Bosch part number 1 455 520 072 Typ 1457 001 KBA 90251). I'm not sure if the diesel fuel temprature is normal or if that could be the reason for my problem.
I have also thought of having breather problems in the fuel tank, but I also get the same situation when driving without the fuel cap on the fuel tank.
So, if anyone can give me some ideas of what this problem can be or what to troubleshoot - it would be much appreciated
(05-23-2017, 03:46 PM)Hello!I have some questions: How many km have you driven since the problem accured, is the intank strainer changed?s123 Hi
Hope somebody can point me in the right direction. I have started getting trouble with my Hymer Mercedes camping car. It have the OM602 5 cylinder 2.9 non-turbo engine.
The engine seems to be in good condition. The car have a low mileage for it age. It have run about 130.000 kilometers (80.000 miles). It does not have any particular noises, except for one of the hyrdaulic valve lifters from time to time ticks. The engine is very easy to start and runs just fine until it have been driven for about 40 km (25 miles), then it starts to "misfire" and loses power and will after a couple of minutes fail to run. If I wait for about 20 minutes, when the engine have become colder again, it will start and run just fine until the same situation repeats itself.
The engine is not overheating. The temprature is normal, maybe at the lower end of the scale. There is no indication of blown head gasket, oil level is correct and the oil is just changed, the coolant water level is fine.
Before last summer i removed the fuel tank and cleaned. At the same time both fuel filters were changed and fuel hoses were inspected and the worn out ones were changed. After this procedure the car were used on a vacation last year where we drove 3000km (1900 miles) after this cleaning procedure.
I have also run a diesel purge with the Liqui Moly Diesel purge (as many found on youtube). The content of the circulated fluid was quite clean and the treatment did not change engine behavior noticeable.
The only thing i found remarkable was that the return diesel hose had an surface temprature at about 50-60 degrees celsius (120-140 degrees Fahrenheit) and the container was quite hot as well. I do not know if this is normal, but the engine have two kind of heating 'gadgets' between the pre-dieselfilter and the main diesel filter. One that seems to take heat from the engine block and one Bosch gadget (looks like a icehockey puck - Bosch part number 1 455 520 072 Typ 1457 001 KBA 90251). I'm not sure if the diesel fuel temprature is normal or if that could be the reason for my problem.
I have also thought of having breather problems in the fuel tank, but I also get the same situation when driving without the fuel cap on the fuel tank.
So, if anyone can give me some ideas of what this problem can be or what to troubleshoot - it would be much appreciated
Algae grows if there is water in the fuel tank,add warmth it begins to grow. Water and algae can be picked up at any refueling
station. Stations that do not sell much diesel are usually the worse offenders.
The fuel strainer can become clogged with the algae,symptoms, many times car can be driven a number of miles before a loss of power, or stalling,let sit for a while,the algae loosens it"s strangehold on the fuel screen and the car can be driven again,for a number of miles
before loss of power again.
Fuel can look clean,that"s because the algae is not passing the fuel screen. ( Possible solution ). Good luck.
I agree but we dont know what is blocking the fuel supply but, the engine is not getting fuel. If there was anything else wrong with the engine it wont run with no problem for 40km.
It is normal with the hot fuel going back to the tank, change the fuel filter if it does not help change the strainer in the tank. You will be fine!
Just a thought. But. My pick up used to do this. Pissed me right off and I changed everything till I found it. Turned out to be the metal stack pipes coming out of the tank. They had gone porous and let a minuscule amount of air in. Ran fine till il built up enough air in the fuel filter to cause stuttering and then a full stop. Changed pipes and no issues. Run the car from a diesel tank under the bonnet for a few days. Rules out the feed pipes
(05-24-2017, 07:33 PM)svengali0 Just guessing really- but the symptoms may be indicating injector and or pre-chamber issues. These may exhibit after the engine is well and truly at operating range under load. A cracked injector housing is likely to be obvious from the get go.
Pull injectors and check for spray pattern and pop pressures.
Get a bore scope and poke this down the injector hole while injectors are out- remove glow plugs first. Check these too while they are out. Use the bore scope to check visually the pre-chamber insides. If one or more of your injectors are washing, pre-chamber failure may be imminent.
Also check that the pre-chambers are properly seated. Though if any aren't, this will be obvious to the ear even at cold- plus you'll notice bubbles at the base of the injector. My 662 is doing this right now. I suspect that the injector and collar nut is not as well tensioned as it should be.
Perform compression tests first, through glow plug holes. Best to do this twice, once cold, once warm.
When the engine begins to play up after a short run (not at the point where it refuses to run), loosen injector lines and see if there is appreciable difference between each pot.
Other possibilities include but are not limited to hydraulic lifter failure (keeping one or more valves open once it gets warm- the lifter is too hard and is locked up), cracked piston (the engine will be breathing heavily- compression test will confirm).
If any or all of the above indicate nothing unusual or wrong, then go to the IP. This may have to be pulled and bench tested. Or find another IP and insert that to see if any change is beneficial.
I'd be guessing 1. injector issues, 2. pre-chamber issues.
HTH
Cheers steu
(05-24-2017, 07:33 PM)svengali0 Just guessing really- but the symptoms may be indicating injector and or pre-chamber issues. These may exhibit after the engine is well and truly at operating range under load. A cracked injector housing is likely to be obvious from the get go.
Pull injectors and check for spray pattern and pop pressures.
Get a bore scope and poke this down the injector hole while injectors are out- remove glow plugs first. Check these too while they are out. Use the bore scope to check visually the pre-chamber insides. If one or more of your injectors are washing, pre-chamber failure may be imminent.
Also check that the pre-chambers are properly seated. Though if any aren't, this will be obvious to the ear even at cold- plus you'll notice bubbles at the base of the injector. My 662 is doing this right now. I suspect that the injector and collar nut is not as well tensioned as it should be.
Perform compression tests first, through glow plug holes. Best to do this twice, once cold, once warm.
When the engine begins to play up after a short run (not at the point where it refuses to run), loosen injector lines and see if there is appreciable difference between each pot.
Other possibilities include but are not limited to hydraulic lifter failure (keeping one or more valves open once it gets warm- the lifter is too hard and is locked up), cracked piston (the engine will be breathing heavily- compression test will confirm).
If any or all of the above indicate nothing unusual or wrong, then go to the IP. This may have to be pulled and bench tested. Or find another IP and insert that to see if any change is beneficial.
I'd be guessing 1. injector issues, 2. pre-chamber issues.
HTH
Cheers steu
Hello!I have some questions: How many km have you driven since the problem accured, is the intank strainer changed?
Hi Jonas
The car have not been driven many km since the problem first occured. Maybe just 200 - 250 km, with quite a predictable outcome - it stalls after a while!
I have not changed the intank stainer, but I think one of the easiest thinks to troubleshoot is to start with the fuel tank.
(05-25-2017, 07:27 AM)Hercules Algae grows if there is water in the fuel tank,add warmth it begins to grow. Water and algae can be picked up at any refueling
station. Stations that do not sell much diesel are usually the worse offenders.
The fuel strainer can become clogged with the algae,symptoms, many times car can be driven a number of miles before a loss of power, or stalling,let sit for a while,the algae loosens it"s strangehold on the fuel screen and the car can be driven again,for a number of miles
before loss of power again.
Fuel can look clean,that"s because the algae is not passing the fuel screen. ( Possible solution ). Good luck.
(05-25-2017, 07:27 AM)Hercules Algae grows if there is water in the fuel tank,add warmth it begins to grow. Water and algae can be picked up at any refueling
station. Stations that do not sell much diesel are usually the worse offenders.
The fuel strainer can become clogged with the algae,symptoms, many times car can be driven a number of miles before a loss of power, or stalling,let sit for a while,the algae loosens it"s strangehold on the fuel screen and the car can be driven again,for a number of miles
before loss of power again.
Fuel can look clean,that"s because the algae is not passing the fuel screen. ( Possible solution ). Good luck.
(05-25-2017, 07:49 AM)Jonas I agree but we dont know what is blocking the fuel supply but, the engine is not getting fuel. If there was anything else wrong with the engine it wont run with no problem for 40km.
It is normal with the hot fuel going back to the tank, change the fuel filter if it does not help change the strainer in the tank. You will be fine!
(05-25-2017, 07:49 AM)Jonas I agree but we dont know what is blocking the fuel supply but, the engine is not getting fuel. If there was anything else wrong with the engine it wont run with no problem for 40km.
It is normal with the hot fuel going back to the tank, change the fuel filter if it does not help change the strainer in the tank. You will be fine!
(05-25-2017, 12:45 PM)Mallinman Just a thought. But. My pick up used to do this. Pissed me right off and I changed everything till I found it. Turned out to be the metal stack pipes coming out of the tank. They had gone porous and let a minuscule amount of air in. Ran fine till il built up enough air in the fuel filter to cause stuttering and then a full stop. Changed pipes and no issues. Run the car from a diesel tank under the bonnet for a few days. Rules out the feed pipes
(05-25-2017, 12:45 PM)Mallinman Just a thought. But. My pick up used to do this. Pissed me right off and I changed everything till I found it. Turned out to be the metal stack pipes coming out of the tank. They had gone porous and let a minuscule amount of air in. Ran fine till il built up enough air in the fuel filter to cause stuttering and then a full stop. Changed pipes and no issues. Run the car from a diesel tank under the bonnet for a few days. Rules out the feed pipes
(05-25-2017, 11:45 PM)Hello the reason i ask about the km is that I had the same problem in my 1998 w140, I changed e verything from the tank to the injectors, filters, strainer orings return hoses etc nothing helped. Then I ran the car sucking diesel from a bucket then it worked I refueled the car, problem solved BAD diesel fuel. I called Statoil(fuelstation in sweden) were I did my last refuel and explained that I got 96L of bad diesel, Statoil admitted that they mixed gasoline in the diesel by mistake I got 3000euro from them to cover my costs. Hello!I have some questions: How many km have you driven since the problem accured, is the intank strainer changed?
Hi Jonas
The car have not been driven many km since the problem first occured. Maybe just 200 - 250 km, with quite a predictable outcome - it stalls after a while!
I have not changed the intank stainer, but I think one of the easiest thinks to troubleshoot is to start with the fuel tank.
(05-25-2017, 11:45 PM)Hello the reason i ask about the km is that I had the same problem in my 1998 w140, I changed e verything from the tank to the injectors, filters, strainer orings return hoses etc nothing helped. Then I ran the car sucking diesel from a bucket then it worked I refueled the car, problem solved BAD diesel fuel. I called Statoil(fuelstation in sweden) were I did my last refuel and explained that I got 96L of bad diesel, Statoil admitted that they mixed gasoline in the diesel by mistake I got 3000euro from them to cover my costs. Hello!I have some questions: How many km have you driven since the problem accured, is the intank strainer changed?
Hi Jonas
The car have not been driven many km since the problem first occured. Maybe just 200 - 250 km, with quite a predictable outcome - it stalls after a while!
I have not changed the intank stainer, but I think one of the easiest thinks to troubleshoot is to start with the fuel tank.
Ussually when the fuel supply is blocked it won't start easily no matter how much you let it cool down.
In farm tractors with DPA rotary pumps if it shuts down when hot that means the pump head is shot.
The inline pump is much tougher but there is still a possibilty. Does it get harder and harder to start when warm ?
I'd say either your injection pump is shot or the valves are worn. But first rule out fuel supply problems by running it from a can of diesel fuel.
Hi
I have removed the tank. Last time I did this, I did not remove the sender unit and cleaned it. I just drained the tank to remove any contaminated diesel. My bad!
For those of you who suggested that the strainer in the tank maybe clogged, you just have to see this:
I was not able to dismount the unit to clean the strainer, so I had to clean it in place. After a good clean i was able to make it look like this:
I'm not sure if this is the only problem, but when it looks like the first picture - for sure you are going to have troubles. So now I'm spending some time to rustproof the diesel tank. I also have to call my Mercedes dealer tomorrow to get hold of a new O-ring, because the present one bear clearly the impression of being collapsed.
I will update you all when I have reassembled the diesel tank and done a test run of the car :-)
(05-28-2017, 04:30 PM)A tip cut out the mesh in the strainer and mount a inline filter in the engine room it is a nightmare to change/clean the strainer if you are on the road. It happend to me in my W124 in the alps no more strainer for me I take care of the debris upstreams.(05-28-2017, 04:20 PM)Jonas Told you so, glad you got it sorted!
Yes, Jonas - thanks a lot for your guidance, hopefully the problem is solved now :-)
(05-28-2017, 04:30 PM)A tip cut out the mesh in the strainer and mount a inline filter in the engine room it is a nightmare to change/clean the strainer if you are on the road. It happend to me in my W124 in the alps no more strainer for me I take care of the debris upstreams.(05-28-2017, 04:20 PM)Jonas Told you so, glad you got it sorted!
Yes, Jonas - thanks a lot for your guidance, hopefully the problem is solved now :-)
(05-28-2017, 06:13 PM)Petar If his hymer camper is based on the T1 van no need to remove the strainer, it is extremely easy to clean since it is removed from the top of the fuel tank, no need to drain it.
(05-28-2017, 06:13 PM)Petar If his hymer camper is based on the T1 van no need to remove the strainer, it is extremely easy to clean since it is removed from the top of the fuel tank, no need to drain it.
So, without jumping to the conclusions it seems like you all have helped me to a solution.
Cleaning out the mesh in the strainer was of course the main reason, but another issue was also the whining noise I had on higher revs just before the engine started to get problems. This was related to one of the hard line plastic diesel lines to the main diesel filter sometime have been replaced by a rubber hose. The internal diameter of this hose was to wide, so it did not fit properly. So when the pump had a hard time pumping diesel, air was dragged in between the hose and the banjo fitting, which made the whining sound, but also dragged air into the diesel line.
I did not have enough hard lines available, so I just cut a little piece an pressed on the banjo, and fitted the rubber hose outside of the plastic part - and tighten it with a hose clamp. Then the fit was proper and the whining noise disappeared.
After a test run today (even if it was not that long) the engine make an impression to be working much healthier.
So I would like to thank all of you who have made comments and lead me into the right direction. Hope this info can be useful also for others!