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GL350 front engine is covered with oil and the serpentine belt is worn out
I wanted to change the engine oil on my 12, GL350 and when I removed the engine cover I found a lot of oil on the front of the engine. The bottom half of the engine is covered with oil. Also the serpentine belt is worn out and there is rubber all over the place from the belt. I purchased the vehicle not too long a go and I know the engine did not look like this when I got it. Currently there are no codes that would indicate that there is a problem, the oil is low but there is no indication that the engine ran without oil. I was slightly on an incline when I checked it. I will check it tomorrow in level surface. I have attached a few pictures. Please let me know if this is a common problem with the engine or am I the lucky one. I can do the work my self I just need to know what am I getting my self into. Thanks
That is not normal. The front should be dry. Clean with wd40 or other suitable solvent and apply dye to oil. Drive for a bit and observe with black light the source of the leak.
Thanks for your reply and suggestions alx. I will start cleaning this evening... looked at the oil filter housing seal and did not see anything unusual.
I thought those always produced a leak down the backside of the engine?
Either way, cleaning first is important. Then observe closely and often. Of course, adding dye is nice - but that's like cheatin'!
It honestly depends on how bad it is. If it’s leaking from the front you have a much SERIOUS case... It’s probably been leaking for a while and has gotten worse.
Oil cooler leak. Rubber oil seals between the engine and oil cooler melted.
I looked at the engine diagram and the oil cooler is located on the top of the engine about half way on the engine. It seems to me that the problem is lower on the front of the engine. How likely is it that the oil filter gasket that goes between the housing and the block would cause the leak?
Last night I started cleaning the front of the engine and worked on it about 1.5h made some progress. I used engine degreaser. it was removing it slowly. This morning I went and purchased some WD40 along with some oil and some dye.
I also checked the oil and there was none showing on the dip stick (has me concerned). If the oil level was too low should the oil level sensor detect the low oil level and send a warning? I looked online to see if I can find some information about the oil level needed to activate the oil message but could not find anything. If you have any info I would appreciate it.
If the engine had a chronic low oil condition the oil level sensor might be sludged and essentially non- operational and showing always presence of oil. Add oil asap.
The engine valley in which which the oil cooler is located has the drains in the back thus oil cooler leaks always show in the back.
Hi Alx,
You are correct. If the sensor was slugged up it would not register the low oil condition. Thinking the same thing, I drained the oil and used a borescope to inspect the crank case. Could not see a lot of things. The camera was not that powerful. I did see several shinny areas. The oil was dirty but normal for a diesel and ended up draining about 5 quarts.
Over the past week I have been scrubbing the front of the engine so I can see what is what. I used a small paint brush with a lot of engine degreaser and managed to clean the front of the engine. I also changed the oil. I was concerned about the quantity of oil left in the engine , but I think the engine is okay.
Yesterday I took the drive belt off and the top idler pulley was rough looking. It had grooves in it from the belt. This brings me to another questions. As I was taking the belt off, I noticed that it goes over the pulley, but the pully is smooth. Shouldn't the pulley it be groove? Looking at the belt diagram, the belt goes over the pulley and it seems that the pulley should have groves in it to coincide with the belt. How is yours? I will call the dealer and see what they say.
After I cleaned the front of the engine, I took it for a ride. I will let my wife drive it to work for a few days and see what happens.
Spoke with the dealer rep. and the idler pully should be grooved. Purchased it for about $50 and installed it. I also replaced the O ring that is in the inlet pipe. I have 2 more O rings coming and we shall see what happens after.
I still have not figured this out. Purchased the O rings. Installed them, along with the new serpentine belt and the grooved idler pulley. Last week my wife called me and she said that she heard a noise and the steering wheel got stiff. I told her to turn around and go home. Luckily she was not too far from home. When I looked at the car the serpentine belt was gone and was wrapped around all the pulleys. Friday went to the dealer, got a new belt and took off all the things in front of the engine that has an O ring. I also checked the turbo and the impeller has play. Does any one know where I can get a rebuilt kit for the turbo? I will upload the video shortly.
believe it or not radial play does not necessary equate to oil consumption... i have yet to figure out that one, but as long as the impeller is not touching the case, sometimes you just leave it alone especially if there is no increased oil consumption indicated
I ended up taking all the plumbing on the air inlet side all they way up to the turbo. There, I found some oil pooling inside the turbo. Checked the radial play of the turbo and, in my opinion, had play. Thinking that the oil can be coming from the turbo, I took the turbo off and checked it. The radial play turned out to be around .01". I also I called Turbokits.com and spoke with a tech there, ( which by the way was very knowledgeable and was not trying to sell me anything. He provide pricing and answered all my questions). He stated that Garrett turbos have some play even when they are brand new . "The bigger the turbo the more radial play.". He also stated that turbos can have some radial play but not axial play. When oil is pumped through, they center them selves and the radial play disappears. Last night I reinstalled the turbo and this evening I will try to finish up the car and see how it goes.
Initially I was thinking that the oil is coming from the filter housing but cannot see from where. I checked the area.
Also I found that the air filters were really dirty. My guess the previous owner did not take replace them as required. Since the right quantity of air was not being introduced into the engine, more air is being sucked from the crank case, thus, more oil was being sucked through the intake. Well, at least, that is my theory... for now.
You're looking in the wrong area. The turbo is going to have oil pooling from the CCV venting in to the intake. Thats why the swirl motor eventually dies on normal engines. Temperature also effects the radial play on a turbo.
To have that amount of oil on the front cover would have to be a result of a boost leak which would throw a code for low or implausible boost pressure without question. The charge pressure line should have zero leaks. No oil, no air, nothing.
Theres not going to be any getting around cleaning the hell out of the front cover and then looking for fresh leaks
Thanks dhurley,
Initially that is what I did. I cleaned the engine as well as I could and looked for leaks. I also replaced the serpentine belt and told my wife to drive the car. Which she did until the belt broke. Your commend about throwing a low boost pressure code makes sense.
As she was driving I checked the leak regularly and even added some dye to the oil. I still cannot find where it is coming from. After the belt broke I cleaned the front of the engine for a second time. This time, since a lot of the plumbing's are off, I cleaned the front even better. I still have to clean the alternator some. It must be a small leak that lands on one of the pulleys, then it is slung around the front cover and all over the place. I am not sure which one. I do not think it is big leak, but enough to make a mess.
check the back of your intercooler for holes... under boost a hole in the intercooler (some times hard to see) will mist a bit oil and spray it in the pattern you showed on your photos. the hole is small enough to not trip underboost codes
otherwise, as i told you before your only chance is clean it up nicely and hope the dye shows somewhere
My 2011 did the same. Oil leak on the front of the engine is likely the oil filter housing to block gasket and or the mid oil filter housing gasket (Oring).. Mine leaked there, got the serpentine belt wet, then chunked the belt which took out the intake air temp sensor.
I believe I found where the oil comes from. There is a steel ring at the "engine charge air duct upstream of charge air cooler" … not my definition. It is what the manual calls it. I will take some pics and post them. The steel ring was not pressed all the way down inside the plastic housing and the O ring was not seated properly. I cleaned the engine last night again and I drove it around the house and no leaks. I will monitor and see how it goes. Now on to the breaking belt problem. Over the weekend installed a new belt and went out of town for the afternoon. I stopped to fuel up and the belt started to shred on one side. Purchased another belt in the event that it broke. But it did not. I will post more details soon.
I believe I found where the oil comes from. There is a steel ring at the "engine charge air duct upstream of charge air cooler" … not my definition. It is what the manual calls it. I will take some pics and post them. The steel ring was not pressed all the way down inside the plastic housing and the O ring was not seated properly. I cleaned the engine last night again and I drove it around the house and no leaks. I will monitor and see how it goes. Now on to the breaking belt problem. Over the weekend installed a new belt and went out of town for the afternoon. I stopped to fuel up and the belt started to shred on one side. Purchased another belt in the event that it broke. But it did not. I will post more details soon.
sounds like a pulley may be out of line. By shredding what do you mean? It’s loosing a rib on the front or back of the belt first or? Did you replace the tensioner? May not have enough tension and jump off. Are you sure it’s routed properly?
Over the weekend installed a new belt and went out of town for the afternoon. I stopped to fuel up and the belt started to shred on one side. Purchased another belt in the event that it broke. But it did not. I will post more details soon.
check all pulleys if they spin freely. you might have a seized or in the process of seizing pulley. look at the diagram and locate them all- some of them are not in plain sight.
As I was cleaning all the mess from the oil leak I checked all the pulleys for radial and axial play and inspected them for nicks burrs... anything that would cause the belt to break. None of the pulleys are spinning hard and or see anything out of the ordinary. I was careful to make sure that the belt was installed properly and was routed properly, engaging the grooves of each pulleys as it should. I did not replace the tensioner yet. As I was driving the car over the weekend it started to shred the belt on the back side (the side close to the engine). See included pic. Also I am attaching the picture of where the oil was leaking from. Drove the car to work yesterday and checked there. Also checked it last night when I got home. So far no leaks.
I believe I found where the oil comes from. There is a steel ring at the "engine charge air duct upstream of charge air cooler" … not my definition. It is what the manual calls it. I will take some pics and post them. The steel ring was not pressed all the way down inside the plastic housing and the O ring was not seated properly. I cleaned the engine last night again and I drove it around the house and no leaks. I will monitor and see how it goes. Now on to the breaking belt problem. Over the weekend installed a new belt and went out of town for the afternoon. I stopped to fuel up and the belt started to shred on one side. Purchased another belt in the event that it broke. But it did not. I will post more details soon.
tracing a leak at the front of my 642, from the intake pipe dripping onto the belt at the alternator. Would love to see the pic you mention and the metal ring before I take it apart (again). Just did cooler seals and pretty sure i replaced every gasket and o-ring possible...
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