Trim Motor Runs but does not Engage Pump?

[Pendlm]

I had an electrical problem with the trim motor on a Mercruiser 228 (1982). Got the electrical problem fixed (bad wire connection from armature to commutator) and reinstalled motor in the pump, and the system back in the boat. Now the motor runs fine but it sounds like the motor is not engaged with the hydraulic pump? Could there simply be air in the system, or is there some trick to engaging the motor back into the hydraulic pump? I have not had the bottom (pump) apart on this system.

Thanks for any help!

 

[Bondo]

Re: Trim Motor Runs but does not Engage Pump?

I had an electrical problem with the trim motor on a Mercruiser 228 (1982). Got the electrical problem fixed (bad wire connection from armature to commutator) and reinstalled motor in the pump, and the system back in the boat. Now the motor runs fine but it sounds like the motor is not engaged with the hydraulic pump? Could there simply be air in the system, or is there some trick to engaging the motor back into the hydraulic pump? I have not had the bottom (pump) apart on this system.

Thanks for any help!

Ayuh,... Welcome Aboard,... Did ya properly engage the end of the motor with it's drive piece in the pump when ya put it back on,..??

Is it full of oil,..??

 

[Fun Times]

Re: Trim Motor Runs but does not Engage Pump?

Hi there, Is your Hydraulic pump assembly a metal reservoir or plastic reservoir?

http://www.mercruiserparts.com/selectDocs.asp?doc_nbr=79170

And do you have the OEM service manual?

 

[Pendlm]

Re: Trim Motor Runs but does not Engage Pump?

I filled it w/ oil just before I put it back in the boat. I'm not sure about engaging it back in the pump-I slid the shaft all the way down into the pump, but I'm thinking it's not properly engaged? I thought since it went all the way in it would be fine?

 

[Pendlm]

Re: Trim Motor Runs but does not Engage Pump?

It appears to be metal. I do have the manual, but it's not crystal clear to me how the shaft engages into the pump

 

[Pendlm]

Re: Trim Motor Runs but does not Engage Pump?

Ayuh,... Welcome Aboard,... Did ya properly engage the end of the motor with it's drive piece in the pump when ya put it back on,..??

Is it full of oil,..??

I've had the motor off the pump once before, but I've never been inside the pump. I note a "coupler" in the attached Figure (#8). Is it possible for this coupler to get out of alignment or fall out of place when the motor shaft is removed? Maybe I need to remove the unit again and remove the valve body assembly (#11) to see what's going on? The pump itself was working fine before it was removed from the boat. The only problem was intermittent motor operation. Thanks for any tips!

 

[Fun Times]

Re: Trim Motor Runs but does not Engage Pump?

I note a "coupler" in the attached Figure (#8). Is it possible for this coupler to get out of alignment or fall out of place when the motor shaft is removed?

That was my first "technical thought" of what might have happen when I first read your question as that could easily happen.

 

[magic11305]

Re: Trim Motor Runs but does not Engage Pump?

I had my trim pump apart to replace the motor, while taking it apart on the work bench I had not noticed that the coupler came out with the motor shaft. Sometime while putting it back together, the coupler fell off of the motor shaft and I reassembled it without. I had the same problem until I realized the coupler was laying on my work bench. Also, it is possible to put the coupler in upside down, which would probably cause the same problem.

 

[Pendlm]

Re: Trim Motor Runs but does not Engage Pump?

Thanks for the responses. I don't think the coupler can come out from inside the pump without taking the pump valve body off. But, I'm thinking that it might have come out of alignment when the shaft was removed. I guess I'll take it apart to find out!

 

[Pendlm]

Fixed: Trim Motor Runs but does not Engage Pump?

Fixed: Trim Motor Runs but does not Engage Pump?

Thanks for the responses. I don't think the coupler can come out from inside the pump without taking the pump valve body off. But, I'm thinking that it might have come out of alignment when the shaft was removed. I guess I'll take it apart to find out!

Yep, took the valve body off and the coupler had come off the pump. Reinstalled coupler, aligned with motor shaft, reassembled, added oil and I seem to be back in business. Thanks for the help!

Some pictures are attached: valve body with coupler, valve body without coupler, and the motor shaft shown coming through the reservoir. This is a Prestolite Pump and the reservoir appears to be a plastic material.