Ok i have checked the restance to all my glow plugs today, they were all around .2 to .4 Ohms. When i turn the key to on, i have 12 volts to all 5 terminals. It will not start without a little shot of starting fluid, even on hot days, what could be the problem, i can't figure it out. When it starts it runs great, how it should.

Employ the KISS principal here. (Keep It Super Simple). Check the cheap and easy things first. Fuel filters. You seem to have checked the glow plugs, ok. Next check valve adjustment. I assume your battery is in good shape. Which priming pump do you have, make sure there is not air in the fuel system. The other unknown would be injectors. If these look ok, then I would move to compression test. Then I would check start of delivery on your IP and timing chain stretch/wear. All you need to start is compression and fuel at the proper time and a diesel will roar to life. Or, make sure you are NOT pumping/touching, or thinking about your accelerator (gas) pedal while trying to start. My diesel will hard start every time if you touch the pedal like you would when starting a gasser. Good luck, keep us posted on your progress. Sorry I did not give details on how to check everything, but I do not know which diesel model you have. Do a search, all of the above have been covered well. Check the "won't start for anything" thread, that thread in itself is an education on MB diesels.

__________________
1984 300D Turbo Sedan (Hilda) 272,115 miles.....
Anthracite Gray/Palamino Leather, I am 3rd owner

2001 Dodge Stratus (Silver) (wifes) 55814 miles...

1982 280TE Wagon Astral Silver Metallic/
Anthracite Velour
260,512 miles (Eva)

1969 230 Sedan Olive Green/Black MBTex
4 Speed Manual
84,213 miles ????
Haus Frau


2004 Boreem Ninja Pocket Bike
Highly Modified 49cc (Ling Ling)

Einigkeit und Recht und Freiheit

Diesels need 3 things to start:
1. Compression - these are a Compression Ignition engine, so must be able to compress the air to the required 22 Bar to develop the heat required for ignition. Valve adjustments are important to allow this to occur. When cold, IDI diesels use glow plugs to compensate for loss of heat to the head.
2. Fuel - The fuel must be injected in the correct spray pattern and at the correct time.
3. Rotation - The starter needs to spin the engine fast enough to compress the air fast enough that the heat is not lost to the cylinder walls, head etc. A poor starter or battery, wrong lube oil grade, or other drag on the engine when cranking can affect the engine's starting.

There may be other issues, but if the engine is cranked fast enough, the engine has acceptable compression, the glow plugs work, and the fuel is injected in a good spray, at the right time, it SHOULD start.

benzracing

I would remove the GPs and check them one at a time by hooking them up to a hot battery.

Your starter has to turn the eng at least 100 rpm

Have you adjusted the valves? Your compression could be low on one or more cylinders for one reason or another.

Remove the vacuum line on the aft end of the injection pump and try it.

__________________


1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"

Benzracing,

Here we go again: Magic cure for everything is to replace the fuel filters.

If the engine runs good once started, the fuel filters are OK.

Usual problem of hard starting is low compression. This can be caused by valves or rings. So first check the clearance of the valves.

If valves are OK, do a compression test.

BTW, what model MB do you have?

Have you tried a push start? If it starts easily with a push start, it cold be a bad starter, battery or battery cable connections.

P E H

Ok i have the 617.950 engine. It's a 1982 300 SD The battery and starter are fine, it cranks over fast. I have not checked the valve clearance yet, i'm planning on that next. Once it starts it runs perfect until it sits for over an hour then it's hard to start again

OK, 1.2 ohms would be a bit better, but at least they are not open.

Confirm current flow quick and easy with courtesy lamp - it should dim when you switch to pre-glow.

OK, so we know you are getting glow to 5 cylinders.

I am 100% in agreement with P.E.H, don't bother with fuel filters.

I suspect an air leak, introduced by an old hand primer pump. A little air in the injector lines will make a hard-start or no-start. Once it's running, after starter fluid boost, the fuel pump must be keeping up with the injector demand.

I'll let others comment, and suggest quick ways to check/replace your hand primer.

Sorry, my OM603 is self-priming....

Best Regards,
Jim

if you want to end this problem look no further than the vacuum line that goes to the shut off valve on the IP, unplug it and you will see the stop lever go back up ( if thats the prob u will see the lever all the way down almost touching the body of the IP ) this problem is caused by a vacuum malfuntion causing residual vacuum to remain on the line, someone might have switched the climate control lines by mistake it seems like people keep having this problem and they check the filters and chain stretch and injectors and glow plugs and so on. I'm of the opinion that if it starts perfect when cold ( always true with this problem ) then it should start even easier when hot UNLESS air was introduced to all injector lines at the same time (air in one or two lines will make it run rough but not prevent it from starting at all.

ok guys I messed up I though the tread read "it wont start when its hot " what I said really appies when is the "hot starting problem " how I confused the two I dont know but I would still check for residual vac to the shut off valve on any problem where is hard to start and then it runs perfect lets face it, any residual vac on that line will force the IP to starve the engine of fuel thats exactly what it was designed to do

even still, the vacuum problem is typically just for a 603, not a 617.

another suggestion, possibly check your injectors- after replacing mine, it made a world of difference on that car. it starts with ease now and runs so much better.

__________________


1980 500SE/AMG Euro
1981 500SEL Euro
1982 380SEL
1983 300TD
1983 500SEC/AMG Euro
1984 500SEC
1984 300TD Euro
1986 190E 2.3-16
1986 190E 2.3
1987 300D
1997 C36 AMG
2003 C320T 4matic

past: 1969 280SE 4.5 | 1978 240D | 1978 300D | 1981 300SD | 1981 300SD | 1982 300CD | 1983 300CD | 1983 300SD | 1983 380SEC | 1984 300D | 1984 300D | 1984 300TD | 1984 500SEL | 1984 300SD | 1985 300D | 1986 300E | 1986 560SEL | 1986 560SEL/Carat | 1987 560SEC | 1991 300D 2.5 | 2006 R350

I was having problems with my 1982 300 SD Turbo not starting under 40 degrees. I was little aprehensive about adjusting the valves myself because I never did before. The job took me awhile but I got it done. I could not even get my feeler gauge in the intake or the exhaust. It fired right up and ran alot smoother. I had my first test the other day here in Colorado where it was 17 degrees without being plugged in and it fired right up. So my big problem was the valves need to be adjusted. Who knows the last time it was done. Now my next project is to replace oil filter gasket.

If you're referring to the oilg filter housing to block gasket, try tightening it first before going to the work of replacing it.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

I do.

Are the return lines going from injector to injector leaking? Have you done anywork to the fuel system? Does sound like air.
One of mine has some leaking hoses, and I have to floor it when cranking till it starts to catch, then let off and it fires up.
Got to get that found...

__________________
83 300SD Dark Silver Dark brown inside

Date of OP--4/16/05

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13