screwdriver test

[tntractor]

If a 1600 has been sitting for a while, should I do the screwdriver test before trying to
start it? Also, will one of those engines go into a 77?
 

[oliverkid]

1600 is a rosa master pump not a Bosch. Completely different animal so there is no screwdriver test.
 

[NYOlivers]

I would make sure you have good clean fuel to all the filters and at the injection pump. Prime fuel system with hand pump on lift pump. A good battery, check oil and should be good.
 

[Olliejunkie]

Roosa pumps can stick too. I don't know how to check them. I don't know if they run away but I would be ready to shut the air off.
 

[rrman61]

How about a 1650?
 

[Tramway Guy]

There is a ?screwdriver test? only on American Bosch PSB pumps. Not Roosa Master or any in-line pumps. Those Vosch pumps were used on all 66, 77, 88 and 99 (6-cylinder) as well as Super variants of all those (except for a trial run of very few Super 77s with the Roosa Master) Super 55, and the 3-digit models through about 1961 or so, maybe later. None of the 4-digit tractors had Bosch pumps from the factory.
 

[Dieseltech]

It's Stanadyne/Roosa on both early indirect and late direct injected diesels. Pumps and injectors are different though.
 

[NYOlivers]

Hey Dieseltech: can you explain the "screwdriver test" for people who don't know what it is? Also what should be done to Bosch pumps if they do sit for awhile and what can be done to prevent them from sticking? I know its a little off the original thread, but it did get brought up so I though it would be a time for a refresher. Thanks
 

[Dieseltech]

It's some times helpful on the American Bosch PSB pumps, after removing the fuel control unit and using a small pick or screwdriver to see if the plunger metering sleeve will move up/down freely. Most are stuck after setting awhile, and when the plunger is stuck just turning the engine with stuck internal parts wrecks the pump. Even a free metering sleeve does not mean the plunger is free too though.