Mini starter RPM

[Bobacuda]

When I primed the engine with my Bauer electric drill (up to 1700 rpm), I checked the oil pressure with an ohm meter - about 18 ohms (roughly 70 pounds pressure) and the factory gauge went about 1/3 of the way.

However, when I spin the engine with the mini starter, the factory gauge barely moves and the ohm meter shows about 25-35 ohms (roughly 40-50 pounds).

So, I am convinced this car is the embodiment of Murphy’s Law, and I will now get a mechanical OP gauge.

But this leads to another question - at what RPM does the mini starter spin the engine?

 

[George Jets]

Here is s simple mechanical oil pressure gauge setup.

Guessing the old original mopar starters probably spin the engine at 100 rpm when cranking.

Would guess the newer mini starters are spinning the engine at 300 rpm when cranking.

 

[diymirage]

keep in mind your oil pump runs of your camshaft which runs at half speed of the crank shaft

so, if your starter runs it at 300 RPM the oil pump is only seeing half of that, 150 RPM


when you hook up a priming tool to your drill it is direct drive, so if your drill runs 300 RPM, the oil pump runs at 300 RPM

even if you estimated a little high on 1700 RMP, you are still spinning the pump 10 times as fast with the drill then with the starter


just food for thought

 

[Scody21]

It’s not good to spin the motor over for an extended time to get oil pressure on the gauge. Best is to just fire it up as you’ll have oil pressure in a second or so and this amount of time won’t do any damage..