BJ40 alternator/vacuum pump replacements (1 Viewer)

[Wild Horse Fab]

Good evening. Im hoping for some experienced knowledge to figure out this probably simple question. My 1978 BJ40 with 3.0 started putting out 36 volts of charge so I have replaced the voltage regulator and checked all the connection. After checking again it is still producing 36 volts at idle. I took the alternator off and it has some good place in the pulley and so I am planning to replace it with this one that is supposed to fit.

My question is in regards to the vacuum pump as it looks different on mine. My current vacuum pump has two hoses that come from the oil filter connector with on going to the top banjo bolt and one coming from the back of the vacuum pump and then the suction port is on the passenger side. This vacuum pump only appears to have one banjo bolt on the top and the suction port on the back. Where does the other oil line connect? Thank you all for your help.

 

[duncanrm]

 

[Wild Horse Fab]

Thank you so much. Duncanrm.

 

[Wild Horse Fab]

Sorry guys one last rookie question. On the oil bracket, which port is the vacuum feed port and which one is the vacuum return? Also, the return like doesn't need to have a banjo fitting due to pressure? Thanks again.

 

[lacalvette]

The only port with vacuum is the one that Duncanrm identified on his picture.

The vacuum pump is a vane type pump wich need lubrication and engine’s oil is used for that.

This alternator also use the engine oil to lubricate his rear bushing bearing.

So oil inlet is near the rear of the alternator, before the vac pump, since it is from the engine lubricating pump, it is under pressure (between 5-75 psi).

The outlet is on the very back of the vacuum pump and drain oil to the engine sump. Since the sump is vented to the atmosphere, there is no pressure hence no need for a banjo bolt.

 

[Wild Horse Fab]

The only port with vacuum is the one that Duncanrm identified on his picture.

The vacuum pump is a vane type pump wich need lubrication and engine’s oil is used for that.

This alternator also use the engine oil to lubricate his rear bushing bearing.

So oil inlet is near the rear of the alternator, before the vac pump, since it is from the engine lubricating pump, it is under pressure (between 5-75 psi).

The outlet is on the very back of the vacuum pump and drain oil to the engine sump. Since the sump is vented to the atmosphere, there is no pressure hence no need for a banjo bolt.

Thank you for the response. I should have been more clear in my follow up question. I understand how the new pump works now and what each of the ports are thanks to you and Duncanrm. My question is which hoses from my old pump are the feed and oil return lines so that I ensure that i hook them up to the oil filter bracket correctly. I have attached a picture of the old vacuum pump with hoses and oil filter bracket if anyone would mind telling me which hose is oil feed and which is oil return. Thanks again.

 

[duncanrm]

I am not familar with the feed/return ports on the B Engine.. but on the H series of Engines the feed is the smaller of the two banjos.. good chance its the same on yours. cranking the enigne with both hoses disconnected and seeing were oil squirts out would certainly confirm..

 

[Wild Horse Fab]

Thank you all. Excited to get back on the road.

 

[Wild Horse Fab]

Hello. Sorry to bother you about this again but do you know where I can get the feed line banjo bolt like you have in your picture. My new one only came with a regular bolt and I don’t have an old one. Or maybe what size this bolt and thread pitch it is.