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Discussion Starter #1
guys I just bought my 1978 300d early December and was loving it. Was driving to work today while my BMW e36 is getting repainted and was cruising along the interstate great. Then all of a sudden I notice Im loosing speed and I look down and notice I have no oil pressure and Im over heating( starting to). I put it in neutral and pull over and kill it. Now I had it towed to my mechanic and Im thinking oil pump. It had good oil level after and before an the oil pressure was at 45 like always and my idle pressure was usually 15-35 on the gauge. I mean WTF this engine was purring like a kitten and I had just put all new suspension, steering components and fixed climate controles this sucks!!! Let me know your prognosis
 

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2003 Volvo V70 5 Speed
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Well with no oil pressure odds are the bearings are toast. Odd that you suddenly lost oil pressure without an external oil leak. I think you are right with suspecting the oil pump. It would be a rare failure if it was though. I have never heard of one frying... How many km's on the engine?
 

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1985 380SE
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Did you hear anything pop just before the car started bogging down? A 'pop' and a loss of oil pressure is in many cases the sound of one of the oil cooler lines bursting.
 

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Discussion Starter #4
Hey guys, no I didn't hear any pop etc, and the odometer stopped at 249,689 and the service record book has an entry from 1996 saying odometer stopped... Lol I had just changed the oil twice in the past month one normal change and one because I put a new oil pan on( old one had dents )

Before I bought it it had been sitting for a few years but I changed all fluids etc
 

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W108 250s '67, w123 280ce '77, w123 300d-t '85, w126 300sd '85', w140 s600 '94,w210 e230 '97, bug69
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Has the oil seeped all out from the engine? If not then its a minor problem, maybe just a weak oil pump, its quite impossible to burndry the bearings as even a weak pump could still manage to lubricate the internals enough to make it run, will the engine still start?
 

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Discussion Starter #6
Well I had the tow guy give it a jolt jump from one of those super jump things, it just makes a click like there is not enough juice to crank it and he tried to turn a pulley by hand and it wouldn't budge. I don't think I caught the low oil pressure soon enough
 

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1984 300D
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If there is no external leaks the Oil Pressure loss could have been caused by the Pressure Relief Valve or Spring breaking in the Oil Pump.

It has happened to people before who own the Non-tubo Engines (the engines with a Turbo have a different Chain Drive Oil Pump).

I suppose another issue could be the Oil Pump Drive which is driven somewhat like a Distributor on a Gasser is.
 

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1985 300CD Turbo coupe, 2006 E320 CDI sedan
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I don't think I caught the low oil pressure soon enough
Well, the engine is clearly seized, but now you have to decide whether it's worth the money to find out whether it's economically repairable. Since it already had a quarter million miles 15 years ago, I think I already know the answer.

There are still a lot of OM617 engines out there, the trick is finding a viable prospect (read still running) in an otherwise worthless hulk. Cuz to me anything of indeterminate pedigree (ie: boneyard engine) would have to be rebuilt before I'd stick it into one of my cars.

Now your '78 might otherwise be a peach, I don't know. But on the average - given the parts and labor costs involved - replacing the car might be the more sound investment. That said, I know where to find an excellent '85 turbo coupe .......

//greg//
 

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W108 250s '67, w123 280ce '77, w123 300d-t '85, w126 300sd '85', w140 s600 '94,w210 e230 '97, bug69
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Maybe your starter is busted, you cant turn the flywheel by hand, try to have your starter checked, i will nit easily give up on the car, as there has been no oil starvation, and you were able to turn off the engine asap when the triuble began, so try to check out the starter
 

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2003 Volvo V70 5 Speed
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no point taking the starter off just yet. Just put a socket on the crank and see if you can rotate the engine. If you can't turn it over then the engine is essentially toast.
 

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Discussion Starter #11
Found a motor for 300$ with 148k on it in a car that the transmission went out on. And my mechanic quoted me 500$ to install it. After I get it in I'm gonna check out the old motor and see what happend. What oil do you guys recommend? Was running 15w-40 shell rotella
 

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1967 300
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$800 for a used engine plus install?!

That's awesome. Absolutely awesome. Jump on it! Make sure you can start the engine before you install it. A compression and leak down test will let you know how healthy it is.


Rotella 15w40 is a great oil too.
 

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-1985 300d (champagne/palomino 133k) -1979 300d (dead parts car)
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Found a motor for 300$ with 148k on it in a car that the transmission went out on. And my mechanic quoted me 500$ to install it. After I get it in I'm gonna check out the old motor and see what happend. What oil do you guys recommend? Was running 15w-40 shell rotella
that donor car may actually not have a bad tranny, just the normal vacuum issues. if it really has 148k miles, might be something to look into. but, yeah, sounds like a good price.

are you sure you need a new engine?
 

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Discussion Starter #14
johnnyqnola, Haven't had a chance to check out the old motor yet, but I will, if i don't It would be amazing.

BUT I did go look at the 1978 car with only "148k" it really only had that many miles, and was VERY clean, I took it down the road, it has some terrible growl in the front left wheel and the interior looks like a really really heavy person was driving it. It has very nice silverpaint. I ended up buying the whole car for 850$

I fiddled with the shifter after I bought it, and turns out, all 4 gears work in the trans HA! so all is good there. the paint is nicer than my blue 78 but the body on the blue is in better shape, with no rust at all, this car has some small rust in the bottom of the trunk, but other than that it is a nicer car. right now im torn which car to fix up and use, and weather or not to part the other one. .. . the only real problem with the new car is that it only has a bill of sale, no title, which i dont need but i like having a title.
 

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Discussion Starter #15
ok back to the car with the engine that lost oil pressure, if it was TOTALLY seized and ruined would the crank move at all when cranking the starter? I went over there and just tried to see if it would move at all, it did each time I turned the key to start the car, but just about 1/2 inch to an inch
 
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