She won't start without a block heater & it's only 40 deg!
 

The temperature here has recently dropped and as such the blasted car has stopped starting. Trying to remedy this I changed the oil to Mobil 1 synthetic 5w-40, got a new battery (the old one was thankfully still under Les Schwab warranty), and changed the air filter. (which was filthy)

This leaves me with glow plug problems. They are the old series type and I usually let them glow for over a minute, resulting in the resistence wire getting red hot. Turning the key and..... no go. In desperation I plugged in the block heater for an hour and it started right up. Why would this make a difference when the temp is above freezing (but cold) and the glow plugs are seemingly working?:confused: Secondarily what is a good test for serial plugs (all I can find are resistence tests which are questionable for this type of plug)


ERRRRGH, stress level rising.:rifle:

Are you sure that ALL of the glow plugs are working? Dash light comes on?

cold start difficulties
 

The block heater warms the oil in the engine's oil circuit. The warmer the oil at all the machine fits, the friction drops dramatically, plus the block heater warms the pre-combustion chamber. Then when you glow her, she start's right up. Same as my 220d with block heater. Also, you need the largest battery, or two batterie's hooked in parallel so that you have sufficient current to run both glow plugs and starter. The speed at which the starter turns the engine over is critical, the faster the better. Bottom line, use the block heater in cold weather whenever you have access to an outlet. There are a large number of threads describing in detail how to test your glow plugs. Try this one, it has pictures and text explaining the testing procedures step by step. www.dieselgiant.com/glowplugrepair.htm

When were the valves last adjusted? How old are the fuel filters? I'd update the glow plugs to the newer style.

My 300SD is pretty tired and it fired up the other day at 30 degrees without a block heater. 15w-40 dino in the sump to! Your car should start unless it has no compression.

I found that when I did my veg oil conversion, she started harder. My advice would be to upgrade your glowplug system to accept the pencil type parallel plugs. At 40 degrees (with good compression) she should fire right up.

do a diesel purge (listed on that same site... dig around a bit) and replace BOTH filters... Mine started a TON better when cold out after a new volt reg, air filter, a diesel purge, and the fuel filters... In that order

Have fun
~Nate

Valves: 2,000 miles ago
Filters: All filters 3 weeks ago
Diesel purge: 700 miles ago (and done right, seperate tank, two cans)

I have heard bad things about updating the 75 & 76 300d to parallel plugs. (usually relays burning out) If I updated I would have to install a generic relay and switch which, at this point, I'm seriously considering.

But at above freezing I shouldn't need one. I would be OK with this solution if there was a plug-in where I park but none such exists (I drive this car to school, there's no outlets and the block is stone cold by the end of the day) Sitting in the Tualatin High parking lot and cranking forever attracts unwanted attention.

I hate to say this but check the compression. 40 isn't that cold with a block heater you shouldn't really need glow plugs at that temp.