Topic: Need to replace an oil pump?

[JHansen]

Hi-

Any recommendations on replacing oil pump on a CB400 freshly rebuilt? (or in process of).

I'm leaning towards going with new, but if these things last forever, do I need to? The old pump has 30000 miles on it. Any idea where to score one? I'm having a devil of a time locating one.

Any tests I can perform to make sure the old one is up to snuff?

All advice appreciated! Best, John

[JHansen]

Hi-

Any recommendations on replacing oil pump on a CB400 freshly rebuilt? (or in process of).

I'm leaning towards going with new, but if these things last forever, do I need to? The old pump has 30000 miles on it. Any idea where to score one? I'm having a devil of a time locating one.

Any tests I can perform to make sure the old one is up to snuff?

All advice appreciated! Best, John

Addition--- My Honda dealer thinks he can get me one, cost: $160us. Ouch!

What to do, what to do!

[Bob Wessner]

I don't know about the 400 manual, but my 750 shop manual specifies wear limits for the oil pump, beyond which replacement or parts replacements are called for.

[HondaMan]

Experience shows: over 25,000 miles on 500/550 and 750, pump flow drops almost 25%, pressure drops about 10 PSI from new.
If you're wanting to play with the revs, try to get a new pump. It makes quite a difference if you run lighter oil. If you can't get a pump, use heavier oil. At 30k miles, at least use 15-40 oil: 20-50 in summertime. This will improve the pressure and help with flow.