I may have an issue with my trim pump, but I'm not sure where to start.

[rhillman75]

I have a 1989 Regal Ambassador 233xl with the 5.7 Mercruiser and what I have been told is, the usual trim pump. I am experiencing a "grinding noise" that only happens when I trim "down". At times the noise is low and at times it is high. This "grinding noise does not happen when I trim up or trailer up. The tank was low so I did refill it, however the noise remains the same. Does this sound like an air in the line issue or is the pump shot? If it's air, how do I bleed the system?

 

[alldodge]

I have a 1989 Regal Ambassador 233xl with the 5.7 Mercruiser and what I have been told is, the usual trim pump. I am experiencing a "grinding noise" that only happens when I trim "down". At times the noise is low and at times it is high. This "grinding noise does not happen when I trim up or trailer up. The tank was low so I did refill it, however the noise remains the same. Does this sound like an air in the line issue or is the pump shot? If it's air, how do I bleed the system?

If you hearing the sound without the engine running the my guess would be there is still air in the system. You can keep cycling up/down and it should purge after some times, keep an eye on the oil level. Like many sounds they are hard to explain in words.

Are you seeing any abnormal signs of movement at the drive?

 

[gm280]

Again ALLDodge is spot on. If you see a smooth up down motion when trimming, then it does sound like air and cycling it will bleed that air out. But since you only hear that grinding noise when down trimming, you need to look at everything around the engine to see if something else is making the noise. Because the pump doesn't know up from down. It just runs and builds hydraulic fluid pressure. How it switches that pressure could be the issue.