DeFever 44 upper helm steering leak

Hi,

Well the good news is we are new owners of a 1990 DF 44: bad news is the delivery Captain is reporting a fluid leak from the upper helm Teleflex Seastar system. It was noted the filler cap in the upper helm has recently been replaced with a closed cap ( no vent hole) should there be a vented cap? If so thinking this could be the cause of fluid being forced past the helm pump seals. If no vent needed then probably the helm pump seal has gone.

Captain is currently underway south of Milwaukee trying to beat the weather to get to Hammond to make the river run.

Thoughts anyone ?


Thanks.

Congrats on your new boat. I believe it is supposed to be vented. But look for a manual to make sure.

If you have the system I think you do then YES, the upper cap must be a vented type.
Otherwise pressure changes from warming ambient air temperatures, sunshine hitting the dash area the pump is mounted to or
a temp. increase from autopilot pump operation will cause fluid expansion. If there is no venting then fluid can be forced past otherwise good seals.

The only system I am aware of that is not vented uses a small reservoir which is in fact pressurized at a low value by pumping air in. It is Hynautic. But the system is designed for that operation.

If the old cap was simply a threaded plumbing cap with a hole drilled into it then there are sintered bronze filters that can be had from hydraulic and pneumatic specialty shops. These do a good job of keeping dirt out yet allowing air interchange to prevent pressure changes in the system forcing leaks.

Install a vent of some sort, clean the oil up and monitor for further leakage.
If it does not stop then the seal may be the problem but also maybe caused by the lack of a vent.

I actually had a leak at the upper helm caused by no vent which was instantly fixed when I added a vented plug. I recommend checking for a vent and installing one if none is present before you do anything else.

Ken

Vented cap needed for sure. Closed cap is for lower helm station only if it is a dual station set up.

Add a vent, what will it hurt? As long as you are not running a pressurized system. My Hynautic system requires 30 pounds of pressure to operate.

I think that, if nothing else, the vent will allow you to find the main leak. It might be a two person job, one to spin the wheel and the other to crawl around and spot the drip.

pete