t-stat housing check balls???/
 

http://www.mercruiserparts.com/bulle...1999/EN_02.PDF
I know what they are and how they work, but why do some motors have them and some not? Same housing.

Thanks

Re: t-stat housing check balls???/
 

Anyone has a motor that uses this housing but w/o the check balls?

Trying to determine under what circumstances they are not used.

Re: t-stat housing check balls???/
 

closed cooling

Re: t-stat housing check balls???/
 

Thanks.
Will I be able to run w/o the balls until I can get a set ordered? Standard cooling. I'm going to replace my 2 hose MPI housings for this unit this weekend to see if I can get my 50psi WP in check w/o going the relief valve setup. If it works as expect, I'll order the check valve assembly Mon.

Re: t-stat housing check balls???/
 

cant answer that never tried to do her, I mean it, I mean run ..........,


hell you know what I mean, with out balls



Let me Know how YOU make out

Re: t-stat housing check balls???/
 

The housing with "balls" is usually for an Alpha drive. They restrict water flow to the exhaust risers at idle. The water pump in the Alpha does not move enough water to cool everything at idle. Without the check balls too much water flows to the exahust causing the engine to overheat.
The Bravo pump moves far more water at idle than the Alpha. That's why the check balls aren't used in that application.

Re: t-stat housing check balls???/
 

These balls on a spring allow water to bypass the t-stat when it's closed and go to the exhaust. When the t-stat opens the balls somewhat close and force more water through the motor. I would watch your engine temps if running without them.

May not be an issue.

Re: t-stat housing check balls???/
 

You may want to check. I think the thermostat housing was redesigned with a more restictive opening to eliminate the checkballs. I think I remember seeing a TSB regarding this.
Gary

Re: t-stat housing check balls???/
 

???

They came on my stock 2002 model 500 EFI's with Bravo XR drives.

Re: t-stat housing check balls???/
 

Check this out:
http://www.marinemechanic.com/site/PAGE260.htm
http://www.marinemechanic.com/site/PAGE261.htm
Gary

Re: t-stat housing check balls???/
 

rdactive, THANKS! Just what I needed. And to think I made a set of balls and springs to install until I could order a set. I even put a little chamfer on the housing thinking it deteriated away over time. I got these housing from a buddy off his '93 502's. Will leave them out.
Off to the lake!
Jerry

Re: t-stat housing check balls???/
 

what he says is for the most pat correct usually the mtr will what I call cycle.......run about 140 go up to 180 then drop to 14 and bact to 180

Re: t-stat housing check balls???/
 

Update.

Used above housing w/o the check balls.

Pressure is even higher now, even though there are 4 hoses exiting this housing compared to my stock original 2 hose housing. Thinking the bypass circut holes are too small in the tried housing.

Not a happy camper!