Really bad news - PeachParts Mercedes-Benz Forum

cam tam abrams · #1 05-29-2009, 11:26 PM

Just bought a 1984 300Turbo diesel.I had alot of smoke and shaking so I took it to a local shop. Today I was told the car has a cracked cylinder and damage to engine block. I am pretty sure that translates to a new engine. I have love for this car and it is very clean but it is worth it? Should I just walk away? Paid 2500 for the car and already put 500 into it.

Oracle12345 · #2 05-29-2009, 11:28 PM

if it is good as you say, you might want to buy a lower block from metric motors or a good junkyard motor for $600 or more

TylerH860 · #3 05-29-2009, 11:30 PM

How did they come to that conclusion? The mechanics could be ignorant or trying to pull a fast one on you. What color is the smoke?

If the car needs a new motor, I would only do it if the paint, body and interior are in good condition. A new motor doesn't make any financial sense. A good used one does, but takes some shopping to find the right one. There are plenty of wrecked or severely rusted diesels ready to give a heart transplant.

Whiskeydan · #4 05-29-2009, 11:42 PM

I suspect the shop incorrect. That is very rare for this car/engine.
Walking away is your choice. Jumping in and trying to figure out what might be wrong (with support from this forum) is an alternative.

Oracle12345 · #5 05-29-2009, 11:45 PM

Quote:

Originally Posted by Whiskeydan

I suspect the shop incorrect. That is very rare for this car/engine.
Walking away is your choice. Jumping in and trying to figure out what might be wrong (with support from this forum) is an alternative.

the shop could be wrong but the fact its smoking and shaking could be a combination of many things which could be:

poor maintained car(no regular oil changes, wrong oil)
fuel system problems

whatever it is its gonna be expensive

Oracle12345 · #6 05-29-2009, 11:50 PM

Quote:

Originally Posted by TylerH860

How did they come to that conclusion? The mechanics could be ignorant or trying to pull a fast one on you. What color is the smoke?

If the car needs a new motor, I would only do it if the paint, body and interior are in good condition. A new motor doesn't make any financial sense. A good used one does, but takes some shopping to find the right one. There are plenty of wrecked or severely rusted diesels ready to give a heart transplant.

snap on and other companies makes a special tool which allows techs to examine the combustion area(ie pistons and other things)

http://buy1.snapon.com/catalog/item.asp?P65=&tool=all&item_ID=81957&group_ID=21604&store=snapon-store&dir=catalog

http://buy1.snapon.com/catalog/item.asp?P65=&tool=all&item_ID=65317&group_ID=1414&store=snapon-store&dir=catalog

Whiskeydan · #7 05-29-2009, 11:55 PM

Simple compression/leakdown check???

Oracle12345 · #8 05-30-2009, 12:00 AM

Quote:

Originally Posted by Whiskeydan

Simple compression/leakdown check???

is where would i start and then make my decision based of those numbers

moon161 · #9 05-30-2009, 12:24 AM

Bad injector(s), maybe? Shaking can be worsened by bum motor mounts. Cracked cylinder would mean combustion gasses in the coolant. You'd be overheating and blowing coolant.

cam tam abrams · #10 05-30-2009, 12:31 AM

The car has had new glow plugs and valve ajustment.Changed out engine mounts changed oil and filter. The smoke is white sometimes black. It smells really bad too. The radiator is new and the machanic thinks someone was driving this car for a while after it overheated causing the damage. I bought it from the salvation army so they had no details for me there.

Diesel911 · #11 05-30-2009, 01:14 AM

I cannot see any way to distinguish a leaking Head Gasket from a Cracked Cylinder while the Engine is still assembled as the symptoms could be similar. Combustion or compression gases and/or Oil in the Cooling System or Coolant in the Oil. (You could have an External Head Gasket leak but you would most likely hear that.)
Of the two 99.99% favors the bad Head Gasket if the above syptoms exist.
(Now that I think about it a Cracke Cylinder Head might also have the same symptoms.)

With a Bore Scope you might be able to see a Cracked Cylinder but that is slim. Sometimes to find a crack the block needs to be pressure tested.

The Bore Scope might show up other cylinder damage if the engine was overheated.

I would remove the Valve Cover and line up the Camshaft Gear Timing mark with the Camshaft Tower Timing mark with the #1 Cylinder on the Compression stroke and look at the Crankshaft Damper and see what degrees it shows. It may be that the Timing Chain has jumped a tooth.

tobybul · #12 05-30-2009, 07:41 AM

Quote:

Originally Posted by cam tam abrams

Just bought a 1984 300Turbo diesel.I had alot of smoke and shaking so I took it to a local shop. Today I was told the car has a cracked cylinder and damage to engine block. I am pretty sure that translates to a new engine. I have love for this car and it is very clean but it is worth it? Should I just walk away? Paid 2500 for the car and already put 500 into it.

A simple compression test is easy to do. Harbor Freight sells a diesel compression tester for a lot less. I have a set and I've used it.

The shaking may just be bad engine mounts and shocks. The smoking can be one of a few things that make a 617 diesel smoke.

You did not elaborate about the mechanic. Is this someone you know/trust?

argus445 · #13 05-30-2009, 09:22 PM

all the cracked head's i've ever had had more serious problems most vw's have oil in the coolant or coolant in the oil or something. If it's cracked that bad should be smoking white smoke all the time and loosing coolant i'd suspect? How did they come up with the block being damaged it's cast iron???

I've seen head gaskets push out and cause a channel in the head spitting out chunks of metal but i've never seen one burn thru cast iron blocks so i'm curious to see if they're is any white smoke all the time, loosing coolant or coolant in the oil and how they determined the block is damaged too sounds shady!

cmbdiesel · #14 05-30-2009, 09:40 PM

Quote:

Originally Posted by cam tam abrams

Just bought a 1984 300Turbo diesel.I had alot of smoke and shaking so I took it to a local shop. Today I was told the car has a cracked cylinder and damage to engine block. I am pretty sure that translates to a new engine. I have love for this car and it is very clean but it is worth it? Should I just walk away? Paid 2500 for the car and already put 500 into it.

Ask the shop what the compression numbers were, or get them yourself.

Jerry_W · #15 05-31-2009, 02:01 AM

While a bore scope could reveal a crack, these are sleeve engines. A sleeve cracked badly enough to cause block damage and continue to run with a smoke problem and shaking as the only symptoms? I would do my own investigating before throwing in the towel, as others have suggested, a compression tester isn't going to break the bank, or for an ironclad diagnosis, pull the head. For a car you like, the price of a headgasket and some time should be worth it.