OM617 cranks, no start
 

I just bought a 1983 300SD with 244000 miles on it about a week ago. It ran fine, started fine, no smoke, shifted well. I put about 500 miles on it without issue. My only concern was that it appeared to have a very slow leak at the rear main seal, meaning, it would yield maybe 6-7 droplets of oil on the driveway overnight after a drive, possibly less.

I performed a full oil change including oil filter and added a full bottle of Bar's Leaks, and proceeded to drive the vehicle 100-120 miles afterward with no issues. I stopped and started the engine reliably without hesitation 4 or 5 times over that 100-120 miles of use. It appeared the Bar's Leaks stopped the drip.

There were no signs of any problems until I went to start the vehicle on Monday afternoon leaving work (this was the sixth day owning and driving the vehicle), and suddenly it would crank but would not ignite. White smoke puffs from the tailpipe. The battery had plenty of charge.

Fuses are fine. Glow plug light comes on and turns off as usual. One time after trying to crank it, there was a hiss that seemed to come from underneath the car near the rear seats that lasted a second or two and then faded out, which I'm thinking may have been the fuel pump. However it still puffs white smoke as though it's getting fuel afterward.

Any advice would be appreciated.



Also, I paid $1150 for the vehicle. It has some body damage and a bad tie rod, and of course an engine that won't start now, but otherwise OK. As I said, I drove it about 500 miles without any issue. So, I'm not sure if I got a deal or if they copped a steal...

Thoughts?

BTW,

MY name's Vince. I'm 25 and I have an obsession with the OM617 engine and the W126 chassis.

I've been swooning over these cars for ages, and now that I've finally gotten my hands on one I'm rather disappointed that I've run into this issue. I expected to have to put some money into it but I didn't anticipate such a catastrophic failure so early after my purchase.

I'd say that I have an intermediate level of mechanical ability - I've replaced the head gaskets on a GM4100 4.5L Cadillac V8 (KILL IT WITH FIRE!), along with a full valve job and all the mucking-of-the-guts associated with such deep engine work, so...there's that... *shudders, then pukes*


Anyhow, I'm pleased to make everyone's acquaintance. I hope to be around a long time to come sharing stories of 300SD ownership and hopefully many more OM617 restorations to come...


If I can just get this first farker to start-up again!

Go to dieselgiant.com and follow his glow plug checking directions. You probably have some bad glowplugs.

It's not catastrophic. Just scroll thru the first 3 pages of this forum and you're sure to find 3 or 4 threads on no-start conditions.

Hello kerry,

Thank you. I've indeed seen that very page, along with quite a few from here as well. It's certainly part of my diagnostic plans for this weekend once I get the ol' boat back to the relative safety of my home driveway.

I'm wondering if any of the specifics of my case seem outstanding. My biggest concerns at this point are 1. the loud hissing that I heard only once from underneath the vehicle, 2. the white smoke from the muffler, and 3. how all 5 glow plugs would quit all at once.



I'm just suspicious of my purchase. Does this sound in any way as though something seriously wrong could be afoot with the motor? I'm hoping that this supposed diesel mechanic relative that my seller says gave it a fit bill of health wasn't a complete fabrication to cover up the fact it had something seriously wrong with it...

Don't know about the hiss. Fuel pump is on the IP. Is your fuel tank vent operational? Remove the tank cap and see if you can hear air rush in. White smoke is unburned diesel fuel. One or two bad glow plugs can be enough to produce a no-start condition. What's the temperature at your location?

I wouldn't worry about the hissing noise just yet, or that you have a serious problem. There is no pump other than the lift pump and the IP. I would check your GP system. In cold weather the GP's are always the first thing to check out. Even one bad plug can cause hard starting issues. I'd make sure each plug is getting 12 volts. If on isn't check the resistance of the wire going to that plug to see if you have a bad wire. if the are all getting 12v, I'd pull each one out and give them 12 volts and see if they glow bright orange. If not you have a bad plug.

Also if you are running biodiesel and it's cold you may have clogged filters.

Hehe,

This is Texas my friends. Not really the most antagonizing chills here, though 'round late Jan or Feb we might have a freeze or two...maybe...

That's one reason I'm very hesitant to jump on the glow plugs as the culprit. It was indeed my first assessment too. I will certainly be testing the electrical out the first spare afternoon I've got, it just seems odd that a "daily driver" car that hadn't shown any sign of glow plug troubles would fail like this; but does this actually seem plausible?


No BD either...yet. And when I pulled in to fill up last and removed the cap, there wasn't any noticeable sound of a vaccuum being released.

You don't jump on anything. You let the data give you the answers.

In your case, you get a voltmeter and put the positive lead on the tip of one of the glow plugs. The negative lead goes to the battery. Then, you get a helper to turn the key to the #2 position. Read the voltmeter and see if you have approx. 12V.

Open you gas cap and let me know if you hear an inrush of air. It is common for the vent line to become clogged and the car will develope a vacuum in the tank.

Also clogged filters, and without glow plugs starting is gonna be hard.

Also Check for any fuel leaks.

EDIT: I didnt read that you had already checked the fuel cap, Check that there is no vacuum in the line going to the shutoff valve when the key is in the run position.

I appreciate everyone's input. It's been refreshing to hear that it's likely not a serious issue.

As I mentioned, the car is stuck in my workplace parking lot right now (I'm hoping to get it started and avoid exorbitant towing fees). It's impossible to open it up and pull out the GP's or put an Ohm meter to the electrical system during work hours, and (due to the farking asinine daylight savings time), it gets dark about half an hour after works finished... Since there's no outlet out there for a proper work light it makes efficient engine work quite difficult.

Anyhow, any other on the spot diagnostics y'all can think up for me are greatly appreciated. I have the factory service manual handy so if I'm pointed at any particular subsystem that might be the culprit I've got the relevant diagnostic procedures handy and will take a look.

This weekend's going to be fun...

Thanks again,

~ Vince

A battery headlamp would allow you to do an ohm and voltage test in the dark. Shouldn't take more than 10 minutes and it will tell you immediately if you need new glowplugs or not.

When I first got my car, the short cold snap in December 2006, is when I found 2 bad GP's and a blown strip fuse in the GP relay. I had to wait a week for the strip fuse to come in. I also used Bosch GP's. The PO installed Beru GP's andd that was 4 years before I got the car.

Tow start it, wrench at home?

Still haven't been able to work out the logistics of getting the beast home...

But about the hissing - I thought it could have been a vaccuum escaping due to a clogged or stuck breather so I left the cap off and attempted to start...no dice. The hiss lasts for 3-5 seconds after cranking, but ONLY every once and a while; it's not every time that I crank it. When it happens it's definitely coming from the rear on the passengers side.

I tested the GP's with a testing light. They're all recieving 12v just fine. Doesn't mean they're all glowing, but I severely doubt enough plugs could have gone out to go from starting up just fine to no start at all in one trip from home to work.

There is fuel in the little clear plastic filter...if that means anything.

I'm thinking more and more that this is a fuel delivery problem, although I am in fact getting some white smoke from the tailpipe while cranking...

What are some of the best ways to diagnose the fuel system?

easiest and cheapest is to crack the lines at the injectors and crank the engine WOT. Check the nuts for fuel. That will say alot.