howdy, new here as a poster but have observed from a distance, i like the attitude on this forum. With that said, i recently purchased a 80 300TD which has a 79 617 in it. new shocks in back to compensate for self leveling yada.

i bought this beast with full knowlage that it burned some oil. after driving it for about 1000 miles ive gone through the better part of 8 gallons of oil. it smokes like a lab chimpanzee on idle and will smoke but much less while driving its blue smoke and carrys that sickly sweet smell of burnt oil. these things come to mind: piston rings, cylander bore, valve seats, valve guides, valve seals. I recently adjusted the clearances of the valves with a friend, smokes less but still like a science monkey at idle. while there is smoke evident with the crank case oil cap removed, its nothing that makes the cap dance around when loosened.

its my plan to do a head rebuild then a block rebuild when the money is flowing in.

This engine is nat asp, there is a hose/pipe that runs from the underside of the intake manifold down to the upperside of the exhuast mani. where it meets the exhaust mani, its leaking oil.

three questions
what is this hose/pipe?
whats causing this leakage?
could this be the cause of my oil consumption?

all information taken gladly!thanks

That's the oil separator return line ( I think). But, before you start digging too deeply into the engine, be aware that a ruptured diaphragm in the early vacuum pumps will feed oil directly over into the air filter. If you have an early vacuum pump, there will be a line (usually white plastic) going from the pump to the air filter. Look inside this line with the engine running and see if oil is being drawn through it. There might be evidence of oil in it with the engine shut down.
I can't imagine that an engine worn enough to drink 8 gallons of oil in 1000 miles would have enough compression to start. That's a quart every 31 miles. I don't think you can push that much oil past the rings or around the valve stems and still have compression. I'd suspect something else.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Get lots of money, lots and lots of it. You will need it all.

__________________
Junqueyardjim
Christianity, if false, is of no importance, and if true, of infinite importance. The only thing it cannot be is moderately important. C.S. Lewis



1983 Mercedes W123 240D 4 Speed 285,000 on the road with a 617 turbo, beautiful butter yellow, license plate # 83 240D INDIANA

2003 Jaguar Type X, AWD. beautiful, good mileage,
Mom's car, but I won't let her drive it!

thanks for your input will do!

kerry, no evidence of oil in the vacuum line connecting to my air filter.. i hate to be silly but where is my vacuum pump and how can i tell that the diaphram has failed?

Follow that white plastic line back from the air filter to the front left of the engine. It goes into the vacuum pump. If there's no oil in that line, I doubt your vacuum diaphragm has failed.
Are you sure you're not leaking oil?

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

its definitly leaking oil from that oil return line looks like at the gasket but its not a fast leak, this leads me to believe im burning it all, its been quite a hassle to buy all of this oil, it runs on bio but the oil is just as expencive as diesel from the pump at the rate that im using it bummer...

honestly, i'd just take it to a reputable shop for a diagnostic. even if you have to pay a small fee for them to tell you what's wrong, it'll be worth the hassle. trust me, there is too much other stuff to break when going on a goose chase.

__________________
1982 MB 300D-T
Veg Power Two tank conversion

this 617 came from a 79 and was transplanted by the previous owner into the 80TD after he put in shox in the back to compensate for the hydrolic pump.

it has the manifolds from the original 80 engine on it... the 79 engine that i have in this beast lacks the drain hole into its crankcase (located down near the oil pan on the 80 model) where the tube from the breather hose drains the condensed oil from the breather. so he had just plugged the drain hole under the air cleaner (under the breather) with a bolt. this bolt was leaking on to the exhaust mani making me assume that was the leak sight. there was also a puddle of oil in this plugged up receptical, that was making its way into the intake. intake also had a puddle visiable once the top of the air cleaner was off.

Ive taken the bolt out and routed a drain tube from the breather drain to the dipstick.

not so sure this will fix my problem, it would be awesome if this is so.. any other ideas/opionions?

Sounds like a better arrangement. How did you hook the drain tube up to the dipstick tube?

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Sucking a puddle oil into the intake would certainly cause lots of oil burning and blue smoke. However, I'd think you'd need more blowby than you claim to have to push enough oil mist into the intake to burn that quart per 40mi you see.

There's a section in my FSM (14-100) for those model years about checking the vacuum system and EGR to resolve a bunch of issues, including excessive blue/black smoke. But it wouldn't cause the oil consumption.

Also, I wonder how MB expected the oil separator to drain back into the crankcase? There must be something missing or mismatched about your car if there's no place for the oil to go.

__________________
'83 300DTurbo http://badges.fuelly.com/images/smallsig-us/318559.png

Broadband: more lies faster.

Yikes! Eight GALLONS in a thousand miles? You didn't mean QUARTS, did you? I agree with the comment above. If it was burning that much oil, I can't imagine you'd have enough compressioin to start it.

__________________
" We have nothing to fear but the main stream media itself . . . ."- Adapted from Franklin D Roosevelt for the 21st century

OBK #55

1998 Lincoln Continental - Sold
Max 1984 300TD 285,000 miles - Sold
The Dee8gonator 1987 560SEC 196,000 miles - Sold
Orgasmatron - 2006 CLS500 90,000 miles
2002 C320 Wagon 122,000 miles
2016 AMG GTS 12,000 miles

I do not know how smooth this engine is running. If nothing simple turns up do a compression check. You might have a piston or serious wall problem in one cylinder.
The other thing that crossed my mind was a bad head gasket leaking to a cylinder from a passage leading in to or out of the head.
The car shown no indication of having been on waste vegatable oil does it? Apparently some cases have been reported of the wvo getting into the base oil in enough concentration to tear up the cylinder walls. Another observation was stuck rings with wvo. Usually the compression ones though and a good soak with marvel mystery oil seems to help them.
I really hope it is just the oil drain you have re routed to the dipstick though. I always enjoyed the quote by Jim L. My car is smoking for someone else now.

it is mixed and matched! it has the manifolds and air cleaner from an 80 on the 79 block. gee i really hope it isnt the wvo rippen up the cylander walls! i used a hose to rout the condenced oil into the dipstick tube its on the same level as the hose so that it can drain properly, its been smoking less just in the last 24 hours, in my best hopes, the oil puddle in the intake is slowly residing, this is my best hope. are there any holes in the block that i could route this drain tube to that would be more effective than to the dipstick? the engine runs a little rough on a cold start but takes no more than 6 to 8 seconds for my preglows to turn off and to turn over, after about two minutes it smooths out its bumps and off i go! it sounds healthy but then a smooth running engine can be quite decieveing... on the brighter side when it has smoked at idle it gets people off my ass

There's a section in my FSM (14-100) for those model years about checking the vacuum system and EGR to resolve a bunch of issues, including excessive blue/black smoke. But it wouldn't cause the oil consumption.

what is FSM (14-100)?