2005 50 HP mercury water pump question

[alnt]

Hello all,

I've got a 2005 merc 50 HP, and I just changed the impeller, gaskets, etc. According to the manual (seloc and mercury), the torque spec on the housing bolts is supposed to be 60 in-lb. I torqued them to 40 in-lb, and already noticed some deflection in the housing. Should I keep going, or stop there? I was using the threadlocker on the bolts, as recommended.

Thank you

 

[coastalrichard]

Re: 2005 50 HP mercury water pump question

You don't want to damage the pump housing. Can you retest touque with another wrench?

 

[alnt]

Re: 2005 50 HP mercury water pump question

I retested with my larger torque wrench, plus I tried with 2 smaller wrenches (both new) that both gave approximately the same reading. The housing was not deformed prior to removing it, and I took it back off after tightening and it still was not deformed. It is mainly one corner that is "bending". I'm thinking I should just run with it, but is there anything I should watch for after starting this up? Also, as long as there is a good stream coming from the tell tale, do you think I should be OK running like this?

 

[coastalrichard]

Re: 2005 50 HP mercury water pump question

Well, I'll say this, the best way to monitor the condition of your cooling system is by water pressure. Install one with a gauge to monitor from the helm. You'll know long before you have an incident vs. your temp alarm. Good Luck!

 

[Don S]

Re: 2005 50 HP mercury water pump question

If you tightened one bolt down to full torque on one corner bolt, then went to the opposite corner bolt, you would notice things appearing to flex. Try tightening it down by going in stages.

 

[alnt]

Re: 2005 50 HP mercury water pump question

If you tightened one bolt down to full torque on one corner bolt, then went to the opposite corner bolt, you would notice things appearing to flex. Try tightening it down by going in stages.

I tightened them each down to about 25 in lb in a star pattern, then to 40 in lb again in a star pattern. I'm wondering if the replacement plastic washers above and below the impeller were thicker than the originals and now they are pushing up on the center of the housing when I tighten down the bolts, causing the housing to "crown"? I guess I'll try it again but remove one of the washers to make sure that is not the problem.