My son just replaced the chain tensioner on his 190E 2.3-16, which went very well thanks to the instructions posted here. A day or so later, after also replacing the battery, he noticed the oil pressure did not rise after starting the car. So he shut it off. I returned from a business trip and was treated to a demonstration. No odd noises, no chain slap, runs smooth, but no oil pressure. Disconnected the electrical signal line from the sender and the gauge pegs at 3 bar. Connect it and nothing. So we figured it was the sender. Anyone replace one of these? Looks like we will have to bend up a 17 mm Sears Craftsman wrench as there is next to no room for frozen fingers to get near the hex on the back of the sensor. If anyone has any hints, please let me know. Thanks, Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

Sounds about right for a failed unit, but I would double check this, I had one that failed and it pegged at 3 bar, this is on a 85 190E 2.3L 8vlv, not much different as far as I can tell.

Replacement is tricky, I didn't bend wrenches, I took off the whole oil gallery with an extension, then when it's out removing the sender unit is a walk in the park, but the bent wrench idea sounds good also

Let us know how it went and how you bent it exactly.

xp

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1985 190E 2.3L - a constant project.

Hey, This is JimSmith's other son, the one who drives this particular 16v.

Today I had a FIRST robotics meeting so my shop teacher and I used a torch to heat up a Sears 17mm wrench and then bent it twice so I could get the wrench in there and still have some leverage.

I came home pulled the Oil pressure sending unit off and put the new one on, The old one was defiantly broken, you could hear something rattling inside it. I put the new one in, started the car, and 0 oil pressure. I was a little pissed off... well a lot pissed off, but decided to try again, this time I let it idle for about 10sec and the oil pressure came up to 3, so I took her out for a ride.

I had to clean some snow off first, so it was idling for a few min before I went out, pulling out of my driver way the pressure was still at 3, pegged like it always normally was. Then about a half mile or so later I look down and it is about 2.5bar and I was a little concerned but knew that some people here have said that is normal, even though I had never had my oil pressure below 3 before. At this point it just keeps on falling, so I pull over turn the car off, and make sure that there is no oil leaking out of the oil pressure sending unit, there is none. I let the car sit for a few min and start it up again and I am at 1.5bar so I try to get home, I get about half way there before it is at .5bar and pull over again. I let it sit for a new min again and turn the car on and I again had 1.5bar, so I drove the rest of the way home and it started to come back up to about 1.75, but then dropped and was at .5 before I got home. I parked the car and checked for oil leaking again and found none. I have no idea what this all means, it almost looks like another bad gauge, but this one was brand new from Mercedes... anyone have any ideas?

The only other problem that we know of with the car is that there is a bad ground somewhere in the car. Before I changed the Chain Tensioner the left blinker would blink fast ever once and a while, and after I changed the chain tensioner I had a short circuit that was burning the insulation on something under the air filter. This time, however, there was not smoking but that doesn't mean its not there, could this be skewing the oil pressure gauge? I thought that most of the instruments were on the same circuit, so my Voltmeter and some other gauges would be skewed but they are not.

Thanks for any help,
Jim

__________________
1985 190E 2.3-16v Euro
1980 300GD SWB

I just took some pictures of the wrench, one that shows how it goes on and another that just shows it.

I would say that if you were going to do this, you should bend the open end side of the wrench a little past 90 degrees as it will probably fit in there a little better.

Attached Thumbnails

   

__________________
1985 190E 2.3-16v Euro
1980 300GD SWB

We will be attacking the lack of apparent oil pressure this weekend and I was wondering if anyone had any hints to offer. I am planning on taking the filter out, and then looking at the various flow paths there might be for relief valves and thermostats to see if there is a chance one of them has gone bad too.

As my son noted, the old pressure signal sender had loose parts in it. If you just roll it around in your hand it clunks as something inside moves around and the new one did not. I am hoping the new one is not broken as well - if I cannot find another explanation, out it comes and we will see if it now has loose guts.

The manuals I have do not detail the oil system very thoroughly. If anyone can let me know if there is a pressure relief valve, and the overall oil flow path arrangement, it would be greatly appreciated. Other than the oil pressure signal being very alarming as it either sits at zero or floats around from 3 bar to 0.5 bar, there is no noise or vibration while the engine is running to suggest there is no oil flow.

I did look into the oil fill cap at the camshafts directly under the openning, and did not see a bunch of oil slinging around in there, but the oil temperature at the time was probably near 10 degrees F at that time, so the chances are there wasn't a lot of oil vapor or slinging going on anyway.

Without an indication of positive oil pressure this car is sitting around, which is driving my son nuts. It has been on the "disabled" list for a while with the old chain tensioner leaking oil profusely and allowing a great deal of chain slap at start up. Now, with the new chain tensioner in place, and obviously working as intended (no chain slap at start up whatsoever), this new problem is becoming very frustrating. Thanks for any hints you may have, Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

Just in case this is of interest to anyone else, I will update. We changed the oil filter, which looked pretty heavily clogged with junk, but looks can be deceiving. There were also some small aluminum chips.

After changing the filter a restart produced no change in oil pressure measurement. Zero.

So, we opened the filter housing and found it full of oil. Then we took the oil pressure sender off and started the car. The first time there was nothing, maybe a slight spray. We tried it again and oil flowed profusely, making a substantial mess. Then I sucked on the end of the sender fitting and got a little oil out (yeah, in my mouth but it is Delvac 1, so I am expecting it to do wonders on the inside). Did the start and stop thing without the sender in place a few times and got the same result, a gush of oil. So we put the pressure signal sending unit back in, and started. Got 2.5 Bar, and then watched it slowly drop to 1.5 Bar. Started again, and it went to 1.5 Bar and kind of stayed there. The engine sounds perfectly normal through all this, but there is no slinging of oil around on the camshafts at the front of the engine under the oil fill cap.

Confounded. Did a few searches and found a few others with this same problem, or sort of, but never got to the resolution part. Any ideas guys? Thanks, Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

Well for starters I would would get a oil pressure test gauge. Hook it up with the adaptor for your eng. (going to be a tight fit) then you will know once and for all if its a presure problem.

Then you will know if you need to hassel with oil supply.
If you have presure then you will know you need to go the electrical route.
If you suspect a ground even though like you said not likely to only affect oil sender. Just add a jumper cable from your body to eng. block. that will put that question to rest.
But you mentioned you had sometning smoking in the past? Under the air filter housing? I would want to know what that was asap. you may have to pull the gauge cluster and mesure the ohm. resistance in you oil presure sender wire.

So I guess my point is do the oil test and you will know what direction to go.

The Oil PRessure sending wire, as you can sort of see in the second picture, goes right to the dash, it doesn't come near the air intake. That is still concerning, but my oil pressure is much more concerning, but if our next theory does not work out I will investigate that.

Last night while I was at FIRST my father did some hardcore searching of the forum and found someone with a very similar problem. After changing the Chain Tensioner they last oil pressure. They discovered that the oil leaking from the CT got into the voltage regulator and by jostling the alternator to change the CT they moved some of the gunk that had collected on the voltage regulator into a position that either broke it or inhibited some of the contacts. So I am going to get a new voltage regulator and hope for the best, then i will be after that smoking issue.

Thanks for the help,
Jim

By the way, what is under the Air Intake that would start to smoke? What is under it Mechanically and Electrically?

__________________
1985 190E 2.3-16v Euro
1980 300GD SWB

Was asking myself that same question last night.

My car is in storage and its cold and wet here so I was to lazy to go out and try to look under there.

I get what you are saying about the volt. reg. but sense you have a specific prob. with low oil reading on gauge I would still say check presure for sure with hydrolic gauge.

GL

I have a mechanical guage now, but my auto teacher did not have teh correct fitting for my car, so i went ahead and took out the alternator to see what is in there. It is a disgusting thing, by the time i was done my hands were pitch black in oil and filth. When i took the plastic covering off of the back of the alternator leaves and wood chips fell all over me. Its really nasty, but i will probably have to put it back in when we get a fitting for the guage, the only reason i took it out was because i didn't have a car to go get the fitting and i was a little board...
anyway, i took some pics of the alternator here they are.
Ill post them in a few min, i have to edit them so they fit in this board.


Ok, some of them are a little blurry because my digital camera is really bad.

Attached Thumbnails

     

__________________
1985 190E 2.3-16v Euro
1980 300GD SWB

I'm still watching this thread with interest-any update? When my 16v had the tensioner replaced, I lost about a .5 bar of oil pressure at idle if i use the thin stuff. I attributed this to the tensioner itself (and therefore the oil circuit) being different than the original. I have nothing to base that on as I don't know the path the oil takes. IIRC, I read about another person who lost a .5bar or so of pressure in the same way I did.

Strange. Its possible I would guess. But it shouldn't cause an extreme pressure drop as BenzX is reporting.

A check value or something in the updated design must be different. I guess the new ratchet style relys less on oil pressure?

Dan,

What is your oil pressure at idle with the oil nice and hot? What's your mileage? What weight oil?

I have been running 20w-50w in mine. Didn't notice and change in pressure after my tensioner update. The lowest my gauge will go is over 2.5 bar at idle with the oil very hot. The odometer reads 155k.

On an side note, if you read the old post of mine (http://www.peachparts.com/shopforum/showthread.php?t=8723) when I replaced my tensioner, I had an exchange with Benzmac and MBDoc concerning some pieces the they claimed didn't belong within the tensioner cap. I put them in anyways with no ill effects.

BenzX,

I guess we will have to see what that mechanical gauge reads. Reading your father's earlier post about the chain slap, how far apart did you take it to replace the tensioner? New rails and chain guides?

Tinker

Tinker,

I use 15-50 in the summer, thinner stuff in the winter, 10-30 maybe? Mobile synthetic. I went for a 45 minute drive today, oil was hot enough to get into the cooler, at idle (1k, a little low i know), I had a needle's breadth under 2.5. If i goosed it up to 1.1k (where i understand these are meant to idle at?) i have it floating JUST under the peg mark. I just remembered that its time to change it, so i'm probably 3/4 quart low as well. I just replaced my 'oil pump' such as it is, the old one showed no wear.

I have 147k on mine right now, before my o2 light came on i was getting about 25-26 highway driving (i cruise with the rpm's in the sweet-spot and keep my foot out of the 'carb', it helps), i'm down from that but i dont know how much, maybe even to 20 or so.

Weird side issue on the balls/no balls. I vaguely remember one in the cap, but really cannot be sure. If it was there, i didn't remove it. The rachet part of the tensioner is only in use when there is no oil pressure-i don't think that style of mechanism, in and of itself, would necessarily cause lower pressure. I do wonder how similar these updated tensioners really are-mine had the number '43' inscribed on the cap and the body, i took it to mean low-volume production run, maybe hand-fitted to ensure fit. No, I don't think the tensioner design would cause the drastic drop in pressure. If he took the whole cover off though, i bet he could get an internal leak with the oil either going back into the pan or into the h2o.

Good thread-always enjoy the ones JimSmith (and his sons) starts

cheers,
dan

Well we have had no luck so far. We have not been able to find an adapter for the mechanical pressure guage for my car. The threads that are on it are standard and the threads in the engin are metric and everyone i ask says "Yeah, I know exactly what your talking about, but we don't sell them anymore. Try Napa".

We use Mobile 1 Delvac synthetic, i don't know the weight of that, but its good crap.

When i changed the CT I just un bolted it and put the new on on. The head of it sticks out the side of the engine right under the alternator, so i did not change the chain or the guides.

Assuming i am getting pressure, which we are fairly sure i am, it must be an electrical problem. I have had a bad ground for a while now, as sometimes the left blinker would blink fast for no apparent reason (both front and back would blink). Also the guy who owned the car before me had a mangled audio system in the car that we deemed a fire hazard and took it out, but we haven't been able to get all of his wiring out so maybe there is a short somewhere in there...

__________________
1985 190E 2.3-16v Euro
1980 300GD SWB

Benz,

How long did you let the chain go (days, weeks, months?), when it was rattling?

When you drained the oil the last time, did any pieces or bits come out?

You really need to get that mechanical gauge in there. Why not give Earls or BAT (941 355-005, http://www.batinc.net/mocal), a call and see if they have an adaptor in stock.

Tinker