Diesel suffering...

Well... my 1982 300SD Turbo.. is driving me nutz.. Since about 180K its had trouble starting in cold weather.. but now its gone to far.. this past winter I would sit and crank.. on an avrage of 10 min. till it warms up and starts.. even so I have the thickest could of smoke that plooms over my neighbors house.. ( im sure they love it) well recently the weather is warmer but im still having the same problems...The glow plugs are new.. and i guess im running the starter soo much that its starting to go bad.. somtimes it just whines.. and after a couple of trys it gets back to cranking.....any ideas? where should i start is my motor bad.. i have ~240K on the Odo... never had any engine work done.. im running Delo...and occasionaly redline..
Heres whats happining in a nutshell
1. Engine wont start in ~60 degree weather ( California Winter )
2. Starts after 10 min of cranking.
3. Runs fine till left it sits to the next morning.
So any ideas?
Thanks.. i realy dont wana dump my diesel.. or get a rebuild...

[CJ]

The first thing I would check is to make sure the valves are adjusted properly. Incorrect valve settings will cause the problems you are describing. When was the last time you adjusted the valves, they should be done about everyone 15K miles.

[JimSmith]

Jivesh,

There are a couple signs of a dying Diesel, and hardstarting is not really one of them. A perfectly good Diesel can be hard to start if:

1. As noted above, the valve clearances are too small. As the engine runs the valves kind of pound their way out of the head and close the clearance. Which means the valve seals the combustion chamber off later in the stroke, which leads to lower pressures and temperatures in the cylinder at the moment the fuel is injected, and you fail to ignite it. The remedy is to adjust the valves, and do it regularly.

2. The engine turns too slowly due to a worn starter, weak battery (although your battery sounds like it at least started the Winter in good shape) or in some climates, the wrong (too heavy) engine oil. In any case the engine has to turn fast enough so the air in the cylinder being compressed heats enough to exceed the flash temperature of Diesel. If the engine is turning slower, the heat is absorbed by the block and head, and the air temperature never reaches a value high enough to cause ignition, until you run it long enough to heat the block and cylinder head a bit. The remedy here is to change oil to a lighter weight or a synthetic (also of lighter weight), check and replace the battery as necessary, and replace the starter. I found the ones sold by FastLane called "heavy duty" for the 5 and 6 cylinder engines worked great on a 240D.

3. There is an air leak in the fuel system, and when you start cranking the air has to be purged before you really get any fuel injected. I am a little suspicous if you can crank for 10 minutes that you are not filling the cylinder with fuel, unless you have a problem with fuel delivery. This issue can also be associated with clogged filters and leaks. (edit: forgot to point out a remedy) The remedy here is to look for fuel leaks as when the system is pressurized if fuel leaks out, then when it is not, air can leak in. Also, if fuel leaks out while the car is parked/not running, then it is a safe bet that air is leaking in somewhere. Look at the injector connections, especially the little rubber lines that jump from injector to injector, and blanked off one on the last cylinder as well as the fat black rubber hose from the main filter housing to the metal tube that goes back to the tank on the left (driver's side) fender. If the fuel filters (the in-line one and the main unit) have not been changed within a year, change them both. I do this at least annually.

4. You have a glow plug system problem. These can be with the plugs themselves, the fuse, the relay or the connections. In any case, without glow plugs and a block temperature of 60 degrees F, you really can not have any compression or other flaws to expect the car to start. Glow plug system problems are usually indicated by odd dash light behaviour. The remedy is to track down the problem part or parts and replace them (not much help, I know)

5. Combinations and permutations of the above problems, where each aspect can be generally ok, but in combination with one or more other weak performers, the system does not function.

If you need some more help, try posting to the Diesel Forum, where some very experienced and helpful people will most likely chime in to give hints or specific instructions depending on what you need or want. Good luck and I hope this helps. Jim

From what you describe - I lean heavily towards a glow plug circuit problem. If the car is hard starting when cold but starts right up after sitting for an hour or so - It most likely is glow plug related. Since the plugs are new - I would get a cheap multimeter and set it to the 20 volt range. First thing in the morning, don't start the car - hold the black lead of the multimeter to the engine block and put the red wire onto one of the glowplugs - have someone turn the ignition on - if you don't have 12 volts at the glowplug - check your fuse and relay - I am almost certain you have no power to the glowplugs resulting in the hard starting. If your compression was bad - it would crank and crank to start - no matter if the engine was hot or cold - less cranking time when the engine was hot. If it starts up no problem when the engine is warm - - definately check for voltage to glowplugs - I would say 80% - that is your problem. The billowing smoke from the exhaust when it does fire is the unburnt diesel from the cylinders not being hot enough yet for complete combustion - translate - no glowplug activity. Let me know
Maurice

Im going to test the glow plus tonight.. but how much should i expect to pay for a valve adjustment ( So. California) ? Ive had the car sine 80K and from then till now 240K ive never had one done...thanks for all the information!

[JimSmith]

Jivesh,

For most of us on this forum the valve adjustment is a DIY task, but some guys work in shops and can give a quote. I would guess between $100 and $150, as it takes about an hour and I replace the valve cover gasket when I do it. I also clean a lot of stuff and check throttle linkage parts (they have to be disassembled so cleaning and checking them out before putting the stuff back together is not really a big deal but it takes some time), make an effort to have new rubber parts on hand to change the breather hose connection or oil cap if they were leaking, etc. If you have gone over 160K miles without a valve adjustment, I am amazed the car runs at all. I would suspect they are very tight, if not in a zero clearance condition.

Get the valves adjusted, then look at other solutions. Good luck, Jim

[mikemover]

WOW! You've gone that long without a valve adjustment? Hopefully it hasn't done any permanant damage... I bet an adjustment will make it start MUCH better. You may not have any glow plug problems at all, but I'd check it anyway.

A valve adjustment shouldn't run you any more than $100. I'm lazy when it comes to that, so I usually have it done by my shop. I get it done here in Atlanta for less than $70.

Since you haven't had it adjusted in so long, to be safe I'd have them check for timing chain stretch also...If it's beyond a certain tolerance, you'll have to get a new chain.

Mike

That long without a valve adjustment is a problem, but it sounds more like a glow-plug problem. If it was valve adjustment, you should notice it in poor running even after the engine is warmed up.

You might want to check your glow-plug relay, to make sure the glow plugs are turning on. Is your glow-light working?

Well its in the shop, the relay or glow plug control is bad. The starter has gone and the big problem, 1 cylnder has no compression, another is @ 1/2.. comprssion. Im bring it back home. Dont have the time to fix it now.. At this point i dont think a valve adusmtnet will do any good ... thanks for the help though!

[kerry]

Why do you think it is not the valves? If the valves are way too tight, that will drop the compression. Did the shop check the valve clearance?

bad compression is often the result of valves drastically out of adjustment!

Realy? .. I asked my mech. and hes all a valve adjusment wont do anything now... He was asking 4500 to rebuild the engine.. Im goign to go take it to another mecahnic tomarrow and c what he says. thanks.

[haasman]

Where in California? I know a great shop in bay area.

Checking the valves is your least expensive way to quickly figure out what's really going on with your car.

If you live close to me .... I'll do it for free.

Try leaving the key in the ACC position (the position where the glowplug light comes on) for about 15 seconds after the GP light goes out , then try cranking. definetely try this.

Thanks for the offer.. im in so cal though!..
but I got it done and IT STARTS !!!! and runs redicously smooth... I was totaly shocked..
but i guess when one problem goes another one starts this morinin the last injector on the back of the engine is sqirting fuel.. all over.. I think it may have come loose during the valve job? but yeh..
too bad i spent 4 months craking...
i should got this done earler.
I ened up killing my starter in the process.
thanks all!