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-   -   240D hard start. Is my motor on it's last legs? (http://www.peachparts.com/shopforum/diesel-discussion/389503-240d-hard-start-my-motor-its-last-legs.html)

pj67coll 11-01-2017 03:52 PM

240D hard start. Is my motor on it's last legs?
 
Thinking my 240D might be on it's last legs. Over the last month or so its become increasingly difficult to start it in the morning. Though once I get it going its fine for the rest of the day. This morning It took almost five minutes of cranking before it fired up, with a large cloud of greyish blue smoke. Just wondering if the symptom indicates a worn out motor?

I mean it's ok when warmed up. My job requires me to drive around a lot during the day so once it's warm I have no issues but that first cold start is becoming almost impossible.

- Peter.

Diseasel300 11-01-2017 03:59 PM

Time to check glow plugs and adjust the valves.

greazzer 11-01-2017 04:14 PM

Are you losing oil? Holding oil pressure ?

Jarod 11-01-2017 07:01 PM

Could also be air in the fuel system, all the cranking primes it, but in doing so it also pushes some oil past the rings?

sounds reasonable to me. if it were my car, I'd start with glow plugs like diseasel300 said, then if glow plugs are all functional, pump the hand plunger primer pump until you hear the overflow valve release to see if its losing prime

t walgamuth 11-01-2017 07:03 PM

glow plugs....classic symptoms.

Mike D 11-01-2017 07:14 PM

If you pull the glow plugs, do a compression test. 330K on a OM616 is starting to get close to expected life time.

pj67coll 11-01-2017 07:59 PM

I know it's long overdue for a valve adjustment. I plan to do one this weekend. I also have a GP issue. I replaced the plugs about two years ago with Monarks, but subsequently when troubleshooting my antenna I messed something up with continual cycles of the ignition system and my GP light now doesn't work. Though I can hear the relay clicking off after 26 seconds when I'm trying to start it. So don't know what's going on there. I'll probably troubleshoot the GP's as well while I'm "in there" with the valve adjustment. Don't have a compression tester so that will likely be beyond my ability for now. Air in the fuel system is something I'd not considered. Might be an idea to change the fuel filters as well but there's only so much wrenching I can tackle in a weekend.

- Peter.

dkr 11-02-2017 12:19 AM

As long as you're at it you might as well check your battery voltage. It should produce about 12.6V, but may start down to 12.4V or so depending on weather. If your battery is nominally holding a charge, you could have similar symptoms.

Dkr.

BillGrissom 11-02-2017 01:10 AM

I sure wouldn't jump to a conclusion of "worn-out engine". A better test for that is to judge blow-by coming out the oil filler hole when idling (see youtube). In my 5 cyl, a designed-in indication of "failed glow plugs" is that the glow-plug lamp doesn't light when a certain number (2?) have burned out. I imagine your 4 cyl has similar, so that lamp is telling you something. Don't dally, it takes me 1 min to check all glow plugs. I pull the plug in the engine bay and measure ohms from each of the 5 pins to gnd w/ my free HF multimeter. If bad, they measure infinity, good <5 ohm.

I just found a bad one in my 1984 yesterday and replaced it. The old one had an "M" symbol, which could mean Monarch, and I probably installed it ~20K miles ago. Previously, I recall most/all failed ones were Bosch, but maybe just what the PO's used. I installed a cheap VSP one (ebay) and have used for ~3 yrs and don't recall removing any failed VSP's yet. The engine started faster and idled smoother cold with all 5 glow plugs working.

pj67coll 11-02-2017 02:15 AM

I shall be checking battery voltage and glowplugs this weekend amongst the other stuff.

Sure do hope it's not terminal as I've just fixed a bad power steering fluid mess from the failing PS pump front seal last weekend by replacing it with one from a junkyard 300D with 100K less miles on it than mine so I was feeling pretty good about it.

- Peter.

Jarod 11-02-2017 06:12 AM

+1 on the glow plug light being a indicator. sometimes mine doesn't light if there is 1 plug out. but seems more likely when more plugs are bad.

I'd highly doubt its "worn out", especially with it being a little cooler recently, this is the time of year all the starting problems tend to show up for me as well.

I did the resistor mod to show when the plugs are actually active by GP light at half brightness, I love that setup, because if the light doesn't come on at all, a fuse is blown or something is awry, but if it comes on half bright, then I know I've got plugs out.

I've had a bad rash of bad diesel recently, took out my grey car and blue car, clogged primary filters multiple times, and then when I finally got the primary to stay clean and the car still ran like junk I discovered the tank strainer clogged solid.

My dodge survived (to my belief anyway) thanks to a giant goldenrod mesh strainer I put inline with the fuel. it has captured nearly a cup of watery slime during this diesel debacle around me.

I'm slightly curious if tanks got contaminated with water during the hurricanes and such and all that fuel got shipped to East TN. or if the tanks here took on water with all the rain and aftermath we caught.

I've since purchased more giant goldenrod filters and will be locating a spot on both of my cars to place them.

pj67coll 11-02-2017 09:14 AM

Quote:

Originally Posted by Jarod (Post 3761435)

I did the resistor mod to show when the plugs are actually active by GP light at half brightness, I love that setup, because if the light doesn't come on at all, a fuse is blown or something is awry, but if it comes on half bright, then I know I've got plugs out.

Interesting, I'd not heard of that before. That sounds like an excellent idea. I doubt' we have a bad diesel situation here as the problem occurs exclusively at cold start in the morning. No issues for the rest of the day.

- Peter.

barry12345 11-02-2017 10:17 AM

There are only two brands of glow plugs that on average offer decent lifespans. Monarchs are not one of them to my knowledge.

You should address this as soon as possible as the starter and battery are not appreciative of the start cycle currently being used. Bosh glow plugs are about the only good ones easily obtainable for these cars.

Periodic valve clearance checks and adjusted if needed are also pretty high on the list going into colder weather. If not done almost forever best to do it several times in short order.

Personally I also believe the fuel system should also be examined. There are components that weaken or become problematic with age in many cases hiding there. Although in your case the probable major issue is the monarch brand glow plugs. Just checking the resistance of each one should locate any open ones. If you locate any open ones replace them all with bosh.

As for a worn out engine. Usually I base this on base oil consumption with these engines. Never a certainty but if you are going through excessive oil consumption with no leaks things are not great.

I personally like to see better than 1000 miles a quart or less usage on the 616 engines. They burn more Base oil on the highway because the piston speed is much higher than the five and six cylinder diesels. I always assumed their oil control rings where not the best.

I do not know if the glow plug relay on the 616 has any feature that indicates issues. Since I have never lost a glow plug on a 616. Also people assume all kinds of things. Any milage indicated by the odometers on these cars is suspect. Unless there is some reasonable proof it is accurate. Your engine could as easily be a replacement with another than as not. We get these cars usually with few to no service records and past history. Good used lower milage engines where a dime a dozen not that many years back for these cars.

funola 11-02-2017 11:11 AM

Never buy glow plug brands other than Bosch or Beru, which may in time end up with a swollen tip that eventually may fall off. In an engine such as your's, a broken off tip will just wreck the pre-chamber, in engines w/o pre-chamber, it will wreck the piston, valves, head, block.

86-300sdl 11-02-2017 11:30 AM

Glow Plugs
 
Glow plug(s)...your frequent starts during the day cut the "calendar days" kind of longevity measurement.


Over the years with daily multiple starts (4 +) & on two - three year intervals, one or two plugs within a replacement set (bosch & beru) go out, making for hard morning starts. The car never sees <40* F, Even at 50* a single bad plugs makes for an old jalopy like start.


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