Robert Bosch va pump timing

756er

New User
Trying to install a robert bosch va6 pump ,the old pump went bad on my 756,had a new pump on a bad motor 310 ci, but couldn't turn the bad motor over to time pump when I took it off.My question is what do I need to do to get new pump in time.I lined the marks up when I took the old one off.
 
Bosch rotary VA AR, BR, and CR versions have a scribe line on the cam plate edge. With the front pulley in the correct location and # one piston on compression stroke, the scribe line should be just even with the roller cage timing tab.
 
Bosch VA pumps are common to freeze up after setting a long period of time. Anything longer than 8-10 months and the trouble begins. I bet I average one per month show up on my bench stuck or leaking. Make sure the throttle shaft and the shut off work freely without a drag. Disconnect the spring to test them. If they feel stiff or tight you might want to send it off to be resealed. Al
 
If the pump is from a similar engine, turn the replacement cam and align the plate mark so the shaft key will enter. Also be aware on early pumps the cam plate has TWO marks, one has the letter L for counter clockwise rotation next to it. DON'T USE that mark as yours turns clockwise. When I service those pumps I grind the L mark off to avoid confusion. Has the replacement pump been used recently? If not it MAY have internal parts stuck from setting as been mentioned. Be very careful as most parts for that pump are made of Unobtainium..
 
Turning the pump clockwise, the first mark is the correct one. Look closely at the second, it should have the L next to it. Hopefully you don't have a pump that Bubba decided to add his own mark..
 

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