Mercruiser trim pump problem (s)

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CRay45DB

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1989 Merc Alpha 1, Gen I, has been working "strangely" all summer. Had the drive off over last winter, had cylinders off as well for painting. After I assembled, the drive pump did not the same. It was kind of a "whirring" Healthy noise. After I reconnected, there was delays kind of sped up more I used it, ect. There is not loos of fluid, I did bleed the cylinders. Now tonight, it will no longer go up or down. It's the relay, It goes click every time I hit the trim. So, could a bad relay be doing all of this, bad connection, pump not getting all of the power it should, or is a bad relay a little more black and white.

​Thanks!
 
alldodge

alldodge

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CRay45DB said:
1989 Merc Alpha 1, Gen I, has been working "strangely" all summer. Had the drive off over last winter, had cylinders off as well for painting. After I assembled, the drive pump did not the same. It was kind of a "whirring" Healthy noise. After I reconnected, there was delays kind of sped up more I used it, ect. There is not loos of fluid, I did bleed the cylinders. Now tonight, it will no longer go up or down. It's the relay, It goes click every time I hit the trim. So, could a bad relay be doing all of this, bad connection, pump not getting all of the power it should, or is a bad relay a little more black and white.

​Thanks!
Click to expand...

If relay is clicking and the pump is not running then maybe its the relay, need to check the contacts. Could also be the pump or the wiring going to the pump. Here is a wiring diagram
Trim wiring Merc 2012.jpg
 
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CRay45DB

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Well, after replacing the relays, which I could have easily checked the pump but was stupid, it was the pump. Since the boat is an '89, it was probably better to change them out anyways. When I took the pump apart, the o ring had failed and the pump was filled with gear oil, and it was diesel black. I did clean it out, but it was really dead. Fortunately I was able to find just the pump, as don't need everything else, so it was $65 with free shipping. I guess it could have been worse.

Stay tuned, I am sure something else will spring up once I put the new pump in.
 
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CRay45DB

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AllDodge said:
If relay is clicking and the pump is not running then maybe its the relay, need to check the contacts. Could also be the pump or the wiring going to the pump. Here is a wiring diagram
Click to expand...

So now we have diagnosed the problem, kind of. Turns out the motor was filled with gear oil. This one is on me as I was using the Merc book as my guide to the vent for bleeding and the book's version of where vent is is wrong. So, the pump was in pretty bad shape. Found an aftermarket one for $60 bucks. So now the question becomes is where is the vent for bleeding? I see the big bolts on either side for emergency lowering, is that my bleed screw?
 

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alldodge

alldodge

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So now the question becomes is where is the vent for bleeding? I see the big bolts on either side for emergency lowering, is that my bleed screw?
Click to expand...

The pump doesn't need to be bleed, just put 10w-30 oil in it and run the trim up and down. Watch the level and add as needed
 
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CRay45DB

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AllDodge said:
The pump doesn't need to be bleed, just put 10w-30 oil in it and run the trim up and down. Watch the level and add as needed
Click to expand...

OK, then how did I fill the motor up with fluid? I believe you, I am trying to fix the underlying problem. This has done this once before.

Thanks!
 
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CRay45DB

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CRay45DB

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Works like a champ! The pump does swivel on top of the resevoir a little bit. New O ring too. That normal or do I have to really crank the nut down under the resevoir?
 
alldodge

alldodge

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CRay45DB said:
Works like a champ! The pump does swivel on top of the resevoir a little bit. New O ring too. That normal or do I have to really crank the nut down under the resevoir?
Click to expand...

Unable to say if it should move a bit or not, never needed to rebuild one. It does say to torque 25 in LB, which isn't much. So if it is on as the manual states then you should be good. I wouldn't tighten much
 
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CRay45DB

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Thanks for all of your help on this one. Working like a champ...I think:)
 
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