Please explain exactly how you achieved these numbers. Was the starter engaged or stopped during the check?


I agree.

This was with a Fluke DVOM on DC volts. Testing was done while cranking 10 seconds per test with vacuum applied to the shut-off and an assistand placing the leads in the correct spot and observing the meter.

That's the way to check it, but, I remain confused as to how these results can be possible. The starter certainly cannot function with only 5 volts available as a voltage drop AFAIK.

You could confirm it if you placed one lead on the relay (starter side) and the other lead on the housing of the starter during the crank. It would be amazing if this would read 5 volts or so.

I'll have to re-check the results myself this wendsday. My assistant must have been reading the meter wrong.

Sorry, I forgot to add this:

The VAT40 also showed 200A draw on the positive cable while cranking.

How do you read a DVM wrong?

Unless the decimal place is one digit off

This would be about right. You would be losing about .6V in the wiring outside the starter.

Checked again just now in class lab.

+ battery terminal to starter relay/sol= 0.135v
Across the relay (On the starter)= 0.165v
- battery terminal to starter housing= 0.105v
Starter motor + to block= 11.6V

It seems he did not know what the heck he was doing.

This just goes to show: If you want something done right, you must DO IT YOURSELF.

I love it when a plan comes together.

Last winter, one of our two 300Ds was reluctant to start in cold weather. Both have good compression, verified glow plugs, adjusted valves, etc. The current draw of the starter for the engine which started easily was about 200 amps, while the draw for the reluctant engine was 300 to 350 amps. Why? The reluctant starter is nearing the end of its useful life, though it's still in use. It definitely turns the engine more slowly, especially as the weather cools.

Phil

'84 Euro 300D, endures the continental climate well
'85 California 300D, likes warm weather

Anybody know the rpm the starter should be cranking the engine at?

Thanks

No but I have been considering taching the fan and recording again every year. The engine temp and ambient temp would have to be duplicated year to year. Before it starts and if you monitored the batttery voltage under the starter load mught be interesting. I have to wonder what a brand new starter and battery with good wiring and terminals would produce for engine rpms. That would have to be gathered from a good compression engine of course. I just ignore this area as long as the engine catches fast under the existing conditions. Plus no difference is present in the starter sound.

Definition of WINTER???? Are we talking East Coast temps that are normal in January/February (in the teens), or are we referring to Fargo, ND January/February temps (in the -30s - -40s)??? That's a very wide range of "winter." For the two years that I had my car in Fergus Falls, MN/Fargo, ND, I ate a complete set of glow plugs each winter, and even with new glow plugs, doing a double/triple/quad bump on the glow plugs, my 300D was not starting, even if I put 5 wt. oil in the tranny and engine. In fact, even if I put straight kerosene in the radiator (straight coolant/antifreeze froze up also and the plastic hose fitting coming off the radiator snapped off)!!! The only way the 300D could be relied in in winter was if it were garaged, or had a block heater plugged in overnite!!!! Yes, the starter would turn, but I learned the hard way that I would put myself on the outs with AAA if I was not plugged in when I tried to start up in the a.m., as I would run down my battery cranking the engine, trying to get it started. Sometimes, starting fluid would help prevent the need for AAA to come to jumpstart me, but it guaranteed that I would need to replace the glow plugs!!!!

Just my two cents worth, based on my experience . . . but what do I know . . . am just a dumb truckdriver, in the minds of most mechanics out there. . . . LMAO!!!! (not referring to anyone on this site!)

Torie

__________________
1983 300D, the "Avocado"
1976 240D, 4-spd the "Pumpkin", SOLD to Pierre
1984 190D, 2.2L, 5-spd, my intro to MBZ diesels, crashed into in 2002