Volvo 290..I Filled Fluid Res. While Drive Up...Is This Wrong?

[GSB Cruiser]

I am desperately trying to bleed a seemingly endless amount of air out of my trim hydraulic system. I have been reading past posts and already made one myself, but I havnt found any definite answers. I have the old style pump with the resevoir inside it and the filler cap on side. I had the idea of filling the resevoir with fluid in the drive's up position. I did that and it obviously took a lot more fluid. I thought this would help push some air out, But now I just read on an older post that this is wrong. Anybody with any advice, much thanks.

I dont want to ruin a just bought replacement pump that was not very cheap.

 

[Gary H NC]

Re: Volvo 290..I Filled Fluid Res. While Drive Up...Is This Wrong?

Any trim system i have worked on i filled with the drive up,or rams extended.Then move trim thru its full range several time to purge air,then top it off again.It may take several times to get all the air out.

 

[Don S]

Re: Volvo 290..I Filled Fluid Res. While Drive Up...Is This Wrong?

In the Volvo service manual it says to trim drive all the way in (DOWN) and fill. Especially on the old style pump you have.
There is little room for excess fluid.
Just trim it down with the cap out of the reservoir so any excess fluid will come out. Be prepared, it could squirt it all over the place.

 

[GSB Cruiser]

Re: Volvo 290..I Filled Fluid Res. While Drive Up...Is This Wrong?

The only thing is, I've lowered the drive since I filled it while in the raised position. I hope this didnt break anything.

 

[Don S]

Re: Volvo 290..I Filled Fluid Res. While Drive Up...Is This Wrong?

That old style pump is going to take some work to get bled out. One thing that makes it easier, is the manual recommends draining the oil (engine oil originally recommended for trim pump) and using ATF. It's thinner and will bleed and fill faster and easier, and work just as well as the engine oil.
You don't want to mix types, so be sure you drain the cylinders also if you decide to go that way.
Otherwise, it will just take some time to fill and bleed, fill and bleed, till it all gets bled out.
Now you know why they only used that pump for a couple of years then went to the present type with the plastic reservoir.

 

[GSB Cruiser]

Re: Volvo 290..I Filled Fluid Res. While Drive Up...Is This Wrong?

Thanks for the advice. Yeah, I wonder what geniuses were behind the design of that pump. I wish I had the newer style. I will continue the process of bleed and fill.