Can I run my engine with no connection to the alternator? (4 Viewers)

[Eurasiaoverland]

I'm getting to the stage in a full nut and bolt rebuild where I'll put the (diesel) engine and gearbox into the chassis and would like to run the engine without the writing loom. The wiring to the starter and fuel cut solenoid is simple, but I am unsure about the alternator. The alternator has to be there in order to tension the water pump pulley.

It's an internally regulated alternator and has the main positive pole and a separate plug with three wires. I assume these are a ground, the charge warning light and an exciter wire.

I assume that it's bad to run the alternator with no connections, but I'm not sure which I'll need to connect.

Appreciate any help!

 

[vipergrhd]

Yes you can run the alternator without any wire hooked up. Nothing will happen I promise, Better get a wiring diagram to make sure it's connected properly.

 

[duncanrm]

No issues.. alternator wont be affected by not being connected.. it'll happily act as the tensioner for the belt alone and will also allow you to deal with the two oil ports on the block for the vacuum pump whilst the engine is running.

 

[Eurasiaoverland]

No issues.. alternator wont be affected by not being connected.. it'll happily act as the tensioner for the belt alone and will also allow you to deal with the two oil ports on the block for the vacuum pump whilst the engine is running.

Thanks, but are you sure this applies also to an internally regulated alternator?

The engine has onboard vacuum so no alternator based vacuum pump to worry about thankfully.

 

[duncanrm]

Thanks, but are you sure this applies also to an internally regulated alternator?

Absolutely.. with nothing connected its doing nothing more than acting as an idler and there's no plausible scenario under which the alternator would be damaged - no field, no electronics powered up, no load presented to the engine.. its just acting as a free wheeling idler if its not plugged in.