Troubled 617 - PeachParts Mercedes-Benz Forum

paulem · #1 12-27-2003, 02:11 AM

Well. . . I've been driving my '71 220D for about five years now and it has been a great car. Incrediblly reliable, especially since I've gotten into taking care of it appropriately (thanks to this forum).

As much as I love the car, it is pretty darn slow and lacks some of the creature comforts. . . so when I saw an ad in the paper for a $900 obo '81 300D, I jumped on it.

The body is excellent! Not a single bit of rust, great paint, the power windows/sunroof all work at a good pace, the interior is great (not flawless, but much better than my 115). I know the ACC in these things is supposed to be a pain, but I've learned to live without the A/C in my 220 just fine. I figure a sunroof will just increase the airflow - I'll be cool engough.

The catch - the car doesn't run. The PO is a woman who bought the car for her daughter to drive in school (florida). It ran fine for a few years and they then had it shipped here (Boulder, CO) and she drove it once a month while her daughter was away. They were driving about 2 mos. ago on the highway when it puttered to a stop on the side of the road and they couldn't get it started again. I looked at the fuel filters, the primary is completely black - can't see through it at all. The motor won't turn over either, even with a jump. I figured a starter, some Diesel Dr. and a bunch of fuel filters would probably get her running again so I offered $400 and got the car.

1st thing - there is a lot more going here that in my 220. The starter on that car takes about fifteen minutes to replace. This took my 3 hours, and still it doesn't turn the engine over. The old one drew more amps than the tester could register, so I reckon it needed to be replaced anyway. . . But still no turn. I've read here tonight about an Auto-Trans issue that keeps the car from starting in Park when it is malfunctioning, so I will try neutral tomorrow.

I know I need to get the valve cover off and inspect the cam, chain, valves, etc. And I should have tried to turn the engine before I bought it. . . but I figured for $400 I can rebuild/replace the engine. The daughter said the oil was a little low when it died, but still registered on the dipstick.

Gotta get it towed to my garage before I can even get to the crank pulley. The 220 is missing the fan shroud, so it is an easy task. For the 300, I need to pull the shroud, which requires removing the trans cooler lines, etc. What a pain.

Oooh - another strange thing. I opened the fuel tank cap and diesel (clean) shot out everywhere. I quickly closed it, waited about an hour, and tried again, and again diesel everywhere. What could cause such pressure in the tank? Wild guess - but do the algae respirate?

I'm really excited to get this going, but hesitant to try to do a rebuild (haven't been at the MB diesel enough to feel confident about it). Besides the obivous things I should have already done (chain/cam/timing/valve inspection), anyone have any ideas?

Thanks in advance,

Eric
'71 220D 120,400 miles
'81 300D ???

P.E.Haiges · #2 12-27-2003, 04:11 AM

Paulem,

You should be able to get a socket wrench on the crankshaft bolt from the bottom. If you can turn the engine, check the camshaft timing by lineing up the camshaft marks and reading the degrees on the vibration damper.

If the cam timing is off, a valve may be against a piston so don't force the engine to turn. You can remove the cam followers to release the valves so you can turn the engine to check the timing.

I have no explanation for the pressure in the fuel system. There is supposed to be a tank vent that would be prevent pressure from building up or creating a vacuum when tank is emptied by normal use. Although it doesn't seem like fuel could have leaked thru the injectors, because they only open under pressure, maybe the engine is hydrolocked with fuel. Maybe the fuel leaked bcakwards thru the injector overflows.Take out the GP and try turning the engine. If you can now turn the engine, hydrolock is the problem. If fuel squirts out, not too much of a problem. If antifreeze comes out, bigger problem, probably leaking head gasket or cracked head. Check the oil level, if it is way high, fuel or coolant is getting into the oil. You should probably change oil and filter if the oil level is high.

Is there any evidence of oil in the coolant? Possibly leaking head gasket or cracked head if there is.

Take 2 aspirin, do the above and call me in the morning. LOL

P E H

whunter · #3 12-27-2003, 09:18 AM

Hello Eric
Sounds like luck to me.
To find one this cheap with what sounds like basic issues.

Answers:
#1. Do NOT attempt to hand crank until you remove the glow plugs,
#2. Remove the fuel tank cap and leave it off while attempting to crank.
#3. How much for your 1971 220D after you get the 1981 300D running?

Best guess:
Bad no return valve = pressure in tank.

Engine is hydrolocked with fuel = engine won't crank.

Change the oil = new owner base line.

Take 2 diesels, do the above and call me Monday at work.

"Drat", forgot there is supposed to be a tank vent that would prevent pressure from building up or creating a vacuum when tank is emptied by normal use.

psfred · #4 12-27-2003, 10:51 AM

Don't worry about the engine not turning over unless the cam is broken when you pull the valve cover.

Pressure in the fuel tank is weird. You will need to CAREFULLY vent all the pressure off. On a W115 I'd tell you to look for a big dent in the tank, but you would surely know if you'd dented the tank in a W123!.

Get the tank empty, then remove and clean it. It has algae bad. Replace both fuel filters, too -- I suspect the main reason it quit was plugged filters. Expect to replace the tank screen, it's probably corroded too.

Once you get the fuel system clean, crank engine over by hand. No need to remove the injectors, if it rolls over it's fine, and if something is jammed up, you aren't going to do much more damage by hand cranking that breaking the chain on the highway did.

Peter

P.E.Haiges · #5 12-27-2003, 11:12 AM

Paulem,

Read my first post again. I thought of a couple of other things that could be wrong and I edited the post.

P E H

paulem · #6 12-27-2003, 04:03 PM

Took out the GP's, no fuel came out. Dry as a bone. Took the fuel cap off and caught the blowing fuel with a towel, actually, lots of towels. Removed the valve cover - chain is intact, cam is intact, plenty of oil in there. But - I still can't crank it - by hand or by starter. If the engine siezed wouldn't the cam and chain have broken?

I only pulled two of th GP's - gonna pull the rest and see what I find. Also gonna remove the belts (siezed A/C compressor stop crank?).

Got it towed to my garage today - much more suitable work space. A little lunch and then back to it.

Anybody have any other ideas?

Eric

psfred · #7 12-27-2003, 05:37 PM

Eric:

Any oil in the crankcase?

And yes, a locked AC compressor will keep the engine from turning. Should slide on the belt, though. Ditto for the rest.

Can you turn it backwards (don't do more than a small partial turn)?

Oh, and pull the rockers out -- this will permit you to rotate the engine if it is way out of time, or the crank is busted.

Peter

paulem · #8 12-27-2003, 07:20 PM

I finished pulling all the GP's - no fuel so I guess hydrolock is out.
Removed the alternator belt, and the power steering belt (the A/C belt has already been removed).

Still, I can't crank it, CW or CCW.

I'm gonna do a little learnin' from the shop manual to see how to go about remvoing the rockers as psfred has suggested.

I guess what keeps me wondering if is really siezed is that the camshaft and timing chain look fine. I've never seen a siezed engine before - can it be siezed and these things still be ok?

Eric

psfred · #9 12-27-2003, 09:18 PM

Run it out of oil and the bearings melt and stick to the crankshaft.

If you cannot turn it over at this point, I'd just pull it and pull the tranny off (torque converter will stay on the flywheel), the drain any oil left, flip it over, and pull the oilpan. Chances are it's pretty dry and the bearings are shot.

If you are lucky, the only damage will be siezed bearings -- polish the crank, install new bearings, and drive it.

More likely, though, the cylinder walls went too.

Peter

paulem · #10 12-27-2003, 10:09 PM

I'm gonna pull to rockers and look into it a bit more tomorrow, but in the mean time I'm thinking worst case scenario.

Doing a search on the forum, it seems there is a pull your own parts yard in Aurora, just down the road from me, engines for $120! I'm gonna go down and check it out tomorrow and I'm just wondering what I should be looking for. A straight replacement or would a turbo fit as well? Any other engine that would fit easily?

What is the best way to size up an engine in this situation? I'm thinking turn it, check the cam timing, look for general leaks, check fluid levels. Anything else?

I've never done an auto task this intensive, I don't really even have the proper tools yet. There are site that I pulled up on an initial search that list a fold away hoist with a hydrolic jack for $99 . . . too cheap to be worth a darn?

It's a great deal of fun to have the luxury of working on a car that isn't my primary source of transportation. The old 220D is running great!

Eric

Stevo · #11 12-27-2003, 10:39 PM

paulem

"Aurora" If your talking Seattls Aurora, try "Benz Friends" down by Boeing field.

P.E.Haiges · #12 12-28-2003, 01:12 AM

Paulem,

Yes an engine can sieze with out any noticable damage to the valves or camshaft. If it was run out of oil or the oil pump failed, a piston can stick in a cylinder or rod bearings can slip inside each other and jam the crankshaft. Not being able to turn the engine in either makes it seem like either of the 2 latter scenarios is possible.

Either way it is probably an expensive repair. You might have to replace the bearings and crankshaft if it can't be reground which necessitates removing the engine, and the rings should be replaced because once overheated, they won't hold good enough compression for easy starting.

Sorry about the bad news. A recycled or rebuilt engine might be your best bet.

grimgaunt · #13 12-28-2003, 03:45 PM

There are two 617 engines at the yard. The one in a 300CD looks clean and the likely candidate. There is also one with 211 kmi in a 1980 300SD (116 body) .