Just curious. I've got my '92 300D 2.5 running pretty good lately - idles smooth, seems to make about the right amount of power, just seems like a pretty solid driver.

Lately, though, I've noticed crank times seem to be getting longer. I haven't timed it (yet!), but it seems to crank anywhere from a couple seconds sometimes to maybe 4-5 seconds (maybe more?) at other times. The weird thing is, the first crank of the day, the car starts right up! And then throughout the day, the crank times seems to get successively longer - until the next morning, and it starts right up again. This pattern makes no sense to me.

No problems that I've noticed with electrical consumers, and the battery checked out strong during the PPI. Any ideas? Places to look? Or is this well within the range of normal?

Out of curiosity, are the successive starts with the block warm or hot? If so, the glow plug relay may not be cycling the glow plugs on if it thinks the block is hot enough. If the glow plugs aren't energized, it may take a couple extra revolutions before you get ignition.

__________________
Current stable:
1995 E320 149K (Nancy)
1983 500SL 120K (SLoL)

Black Sheep:
1985 524TD 167K (TotalDumpster™)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Yes, exactly - the block is warm, which is why I'm expecting the starts to be quicker than when cold (or at least AS quick), but they're not. Thanks for the explanation.

Any chance the later in the day starts are with the vehicle parked nose uphill... and first start of the day nose downhill? The IP on the 60x motors have o-rings in them that leak with age... changing them isn't difficult.

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Let it glow a little longer before you crank and see if this changes your start, as the system ages it seems the light turns off too soon, especially warm.
New relay or temp sensor maybe?

__________________

Gone to the dark side

- Jeff

Yes...the "idiot light" is not necessarily to be trusted. You can train yourself to ignore it and develop an instinct of sorts as to how long you need to glow given ambient temperature and how warm the engine is.

__________________
14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 154k miles
06 E320 CDI "Rutherford", Black on Tan, 172k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver on Tan, 142k mi, wastegate conversion, ALDA delete

19 Honda CR-V EX 61k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife

The first start of the day is nose slightly downhill, now that you mention it...although the IP was recently re-sealed (well, at least 3 of the seals were, I don't know how many there are in all). The longer starts have been with a warm engine on level ground.

But what is normal, anyway? Are 4-5s cranks concerning at all?

Glow plugs are also new, so I assumed the light was good-to-go. When I first bought the car, the preglow light wouldn't come on until after the car was started, and would stay on for 5-10 minutes afterwards. New plugs fixed all that. I will try giving it a few extra seconds...so it's safe to assume the plugs are being energized even after the light goes out, so long as the key is in the correct position? Sorry, I'm a diesel noob, and didn't even know what a glow plug was until I was shopping this car, lol.

I'm really enjoying learning about this car, though. It's making more and more sense over time, and seems fairly straightforward as far as end user maintenance goes. Thanks for all the info.

I have manual glow on my 85 with 617. On a warm engine, I do not glow and it starts immediately upon turning the key to start. I'd think your engine, being newer, should behave the same (i.e. glowing is not needed) if everything is right.

__________________
85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Can also be too much air is present in the fuel system I would suspect. Might tend to delay start ups.. Just a thought if the glow plugs check out well. I really like it when you hit the key on a diesel and it is right there. Of course when ambient temperatures get too low this is not usually the case.

Yes, plugs are being energized both after light goes out AND after engine starts. If/when you confirm that starts are easier by letting it glow a little longer, I would just ignore the light.

__________________
14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 154k miles
06 E320 CDI "Rutherford", Black on Tan, 172k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver on Tan, 142k mi, wastegate conversion, ALDA delete

19 Honda CR-V EX 61k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife

a healthy 60x will start in less than one revolution, even at -10F if the glow system is good (I have video somewhere, mine always started on the 2nd or 3rd compression).

I don't know what changes to make the light turn off too early, I've replaced a relay, glowplugs, but never the temp-sensor.

__________________

Gone to the dark side

- Jeff

Yes a healthy engine should start incredibly quickly, my brother's OM617 in his W116 300SD usually starts with just bumping the key into the starting position.

__________________
Current: 1975 450SEL, 83 300D, 88 Yugo GVX, 90 300D OM603 swap, 91 F150 4.6 4v swap, 93 190E Sportline LE 3.0L M104 swap, 93 190E Sportline LE Megasquirt, 03 Sprinter, 06 E500 4Matic wagon.

So what should I be concerned about with a long crank?

Car has 224K miles on the odo. All fluids & filters changed about 2000 miles ago (except fuel tank screen, which I didn't know about - on order now). Considering Diesel Purge & injector rebuild shortly. Getting ready to swap wastegate to pressure actuator. Timing chain recently replaced. IP resealed. Pretty extensive PPI, so I don't think any fuel lines or anything would be grossly abnormal or out of spec. No blow-by that I noticed with the oil cap loosened.

First thing to check is the glow-cycle. Older GPs will not get as hot as fast, sit for another 10seconds or so after the glow light goes out. If it starts immediately, possibly just glowplugs or maybe just wait a little longer to start.

Is it taking longer to fire on any cylinder or starting rough?

__________________

Gone to the dark side

- Jeff

GPs are new with reaming performed. I haven't yet tried just letting the plugs energize longer than the light indicates (wife's DD, so I'm a little behind).

It's not starting or running rough. And it's really not even taking that long to start - it's just not right away. I guess it's long enough that I notice and it worries me a little bit.