Final check...can my 82's 617 be saved? - PeachParts Mercedes-Benz Forum

dieseldan44 · #1 07-11-2011, 11:26 PM

I have a donor engine ready for my 82. Question is, I want to know if the 82's block could be of any use to anyone.

Stats:
- 237k, i bought it at 208k this way as a nooooob in '06

- compression 380-360-360-220-240 warm, after valves adjusted
- numbers the same after adding oil
- lots of blowby, not quite tossing the cap off but lots of tea kettle and steam train likeness
- burns quart of oil per 1000 miles
- lots of oil in air cleaner area, with updater breather hose
- does not start below 45 degrees F
- coolant has a distinct dark almost exhaust like color to it
- otherwise runs great once warm. visible smoke at idle, but not horrible.

Question is - with the blow-by present, is there any way it could just be a top-end issue, like a bad head gasket between 4 and 5??

I need to pull the motor anyways - but I dont want to junk a motor that could just need a headgasket. I can at least give/sell it to another forum member if I know the bottom end is good. Or, is there no point in even checking if a lot of blowby is present?

May be cool to take apart a 617 with no consequences....

ROLLGUY · #2 07-11-2011, 11:49 PM

Quote:

Originally Posted by dieseldan44

May be cool to take apart a 617 with no consequences....

You may want to think about a long term rebuild. It is always nice to have a spare 617 around for a rainy day. With blowby like that, I would NOT suspect head gasket, or even valve seals. I would suspect rings. Maybe you could just do a ring job, and valve job and it may last another 300,000 miles. That would not cost much (compared to a complete rebuild). Is the donor engine from the same year and/or same chassis? The reason I ask, is that I put an '85D 617 in my '82 CD, and had to change a lot of parts. The '85 had a sensor on the I P and the adapter plate that I did not want on the '82. It also had no air cleaner oil drain tube. I changed the oil pan, adapter plate, injection pump, and a few other items.

BoiseBenz · #3 07-12-2011, 12:02 AM

What is your oil cap? A plastic cap vs. a metal cap has dramatically different behavior.

Quart per 1k miles? My cursed 603A "consumes" one quart per ~400 miles. Damn*d 617A leaks one quart ~600 miles. Both start on third compression cylinder, regardless of (ambient, un-block-heated) temperature, down to about 5 degrees Farenheit.

YMMV.

dieseldan44 · #4 07-12-2011, 11:49 AM

Plastic cap for the oil - but it rattles a metal one too pretty good.

Putting in a parts car engine when you dont know oil consumption is nerve wracking for sure! The donor engine has like new compression - 380 all across.

spdrun · #5 07-12-2011, 12:25 PM

The cold start issue -- how are the glow plugs? My car would take about a minute to crank up when cold. Turned out that only one out of four glow plugs was working: the other three were open circuit! (Lamp still came on upon starting). Bad fun changing them on a NYC street when it was 10 degrees out.

Stretch · #6 07-12-2011, 12:33 PM

Do a leak down test - or "just" stick some (low pressure) compressed air on each cylinder via the glow plug holes and listen at the following points to get a better impression of engine condition:-

1) Air inlet - valve problem
2) Exhaust - valve problem
3) Bubbles in coolant - head gasket (unlikely to see it though)
4) Oil filler cap - could be piston rings or leaky valve stem seals
5) Dip stick tube - piston rings (compare with #4)

Perform each test with the valves closed!

If you are in any doubt about valves being open or closed - remove the rocker arms.

junqueyardjim · #7 07-12-2011, 12:38 PM

Well they sure are clunkers when you have to sit on one in the garage.
Dry instead storage is the only way to go, and that is tough to do when you are sitting on a junker that you know needs a ton of work. What I would do with a clunker that I wasn't going to rebuilt is to pull off all the accesories and the head. The head is big and clunky, but you can wrap it up in plastic and store it pretty easy. When you get a few bucks ahead, either go through the head yourself or shop it out. You might be surprised at how salable a quality head is. Take really good care of the cam and cover it with heavy oil(think pour on STP), and wrap it very well in plastic.. Keep all cam towers in order or number them in a very positive way. It is easy to ship, (I didn't say cheap) and UPS will bring them door to door. Then take every thing off and I store that kind of stuff in plastic barrels, which used to be called garbage cans. Alternator, starter, A/C and brackets, oil filter assembly and if you are then going to junk it, you should pull the front damper and pulley assembly off. Look how many owners are loosing that front assembly. The crank is also worth pulling, but it does take work. At the same time though, you can separate the aluminum pans, upper and lower and and save them to sell. Can't save them, they are worth the money in junk aluminum. Then remove the crank. Treat it very carefully if you are going to save it to sell. The bearings will all be marked if they are not standard. It will most likely be all standard, if not note what or how the bearing was marked. I wouldn't save the bearing shells. If someone buys it, they should put in new bearings. Now you have the dirty old block. Junk it or keep it. If you keep it, wrap it up in plastic and keep it inside.