slightly rough starting and slow shut off

[chuckr]

tried to search this: my '82 300TD wagon has been running like clockwork, starts easy and settles into a nice idle very quickly, even in our cold snap here in NY and shuts off like it should: today however, it took two times to start and was rough running for about a two mins, then went to shut it off and it was slow to shut down (took about 4 seconds to shut down).

(car has had a valve adjust and seems super strong with great power.)

are these usually related (that is, what would could cause these two issues?). I have read bad gas for hard starting, but for shut-off too? vacuum leak for both? leak in fuel line or hard starting but for shut-off too?

thank you for any advice, my first diesel and been a joy so far.
chuck

[Biodiesel300TD]

I would start with tackling each problem seperately.

Slow shutting down is caused by either a lack of vacuum to the shut-off valve, or a leak shut-off valve. If you have a mity vac hook it up to the shut of valve. And start the car. Give the mity vac a pump or two. The car should shut down. If you have to pump it more than once, your shut-off valve is bad. If it shuts down with one or two pumps then you likely have a leak somewhere else in the system.

A sudden change to hard starting is usually a bad glowplug or two.

[kerry]

Hard start is probably an issue with the glowplugs. Slow shut down could easily be that you didn't run the car long enough to completely charge up the vacuum system so there was less than the usual amount of vacuum to shut it down. I've had that happen in the past.
Sometimes TD's run rough for a while when cold, if the SLS is down and has to be pumped up. Pumping it up puts a load on a cold engine that makes it hesitate some. At least that's been my experience.

[chuckr]

thanks guys. i don't have a mighty vac, but i was going to locate the climate control vac hose and pull it and plug it (my door lock hose is plugged) and try to isolate the shut-off valve and if it shut off fine, then assume i have a leak in the climate system.

had my glow plugs checked recently, and my gp light is operating...i thought if there was a plug issue, that the light would not come on? or perhaps that's in some cases. thanks, chuck

[toomany MBZ]

Properly adjusted valves will help the engine to start. Make sure the gp's are getting voltage and have low resistance, again.
As noted, shut off is a vac issue, I'll suggest plugging off the door lock system only, then try.

[Biodiesel300TD]

The GP light only comes on if two or more plugs are out. One plug burned out plug can make a big difference.

[chuckr]

hi, the valve are adjusted. checked the GPs a month ago, and were okay, will do again (i have a new set hanging around-the current set looks pretty old and i don't know when they were changed last). came home from work - wasn't that cold yesterday (30s) and it started up just fine. I checked my vacuum hoses and nothing visually wrong there, car did turn off okay. perhaps i'm used to a gas car shutting off - is there supposed to be a 'beat' or three before it shuts off? thanks chuck

[toomany MBZ]

Originally Posted by chuckr

is there supposed to be a 'beat' or three before it shuts off? thanks chuck

My SD is like that.

[chuckr]

toomany MBZ, thanks. does the SD have door and climate control vac like mine? are yours working? chuck

[toomany MBZ]

^ No, a different, separate set up. Locks work on the SD, but I've sprung a leak on the CD, that shuts off like it used to since I plugged off the lock system.
Same HVAC unit tho and it's slow, so I think there's a leak there too, just not bad enough for me to tear into the dash.

[kerry]

if you want to check your shut off valve without a mity vac, put a long piece of rubber vacuum hose on it (brown line between IP and oil filter housing) and give a couple of hard sucks with the engine running. It should shut down with no more than 3 good sucks. If you get a mouthful of oil, you'll know the diaphragm has been breached.

[toomany MBZ]

Or if it got as bad as mine you can check the kick panel below the key.
This would shut off when I applied vacuum at the shut off actuator. Installed a new one anyway, problem solved, or at least to where it'll shut off with the key again.

[MBeige]

If you just had the valve adjustment before the symptoms occurred, then I would look at loose vacuum lines around the injector pump area. Removal of the valve cover could have snagged some lines or have gotten them loose, just enough to merit bad starts/shut down. Also, check that the linkages were installed correctly. Maybe there is some binding, enough for the linkages to not reach proper stop angle.