Hi together,
does anyone know if it is possible to run a 1975 DT 250 (Typ 512) with a 1977 Autolube oil pump from a DT 250 MX?

Best regards from Germany
Knuth

No i don't know but have a couple of suggestions for you to check up on until someone else may be able to tell you.
If you have both pumps already,check the scroll wheel inside to see if it's the correct pitch for the scroll on the pump drive shaft.
There are different size pitches for instance,Yamaha TDR 250 and RD 250/350 LC scroll wheels are different despite the pumps looking almost identical to look at.
You could then find out the pump output at idle and at 4000 rpm and see if they are the same.
Somewhere on you tube there's a guy with a DT 250 who demonstrates how to test the output and measurements.
Regards Shyted

I would say no.

I'm not as familiar with the bigger bikes but doesn't the oil pump drive shaft on the earlier 250 models "direct drive" off the end of the crank?

Then Monoshock 250 uses a plastic oil pump gear drive off the crank like a 175?

Those differences make me think that the worm drive ratio and "thread" direction are likely to be incompatible... (one would have to be RH thread and the other LH thread)

Hi Mark, hi shyted,
I disassembled tboth pumps and compare the parts. Now some parts of the NOS pump help to renew the old pump. It woks correct.
And thanks for the info because of the video. It is realy interesting.
Turning the outer wheel by hand is realy boring....200 times with "full throttle" - 200 times with "low throttle".
Best regards to USA
Knuth

Hi Knuth,
which Part was defekt at your pump, and what was interchangeable?

Hello Knuth. Good to see you've fathomed it out.
Regards
Ted