Mercruiser Pre Alpha Power Trim

[THenning]

HI All,

I just bought an older Webbcraft 18V with the Mercruiser 228 V8 305 Engine and what I can only assume is a MC1 Outdrive. My power trim works down, but is very slow on up and won't go up as far as a trailering position. Once it gets to a certain point the Trim motor keeps running but it will not raise any more. The pump appears to be a prestolite and has the numbers 74436A14 on it. I am not able to find any hits on the web for this part number, but I am for 74436A9, are those two parts interchangeable? What I am wondering is should I be looking to the motor or the rams for this problem? Are any pictures needed?

On a side note, I'm new to owning a boat but mechanically inclined (do my own car repairs, not afraid of soldering, can rebuild carbs/Work on motors etc) beyond this trim problem I'm looking to replace the impeller in the lower gear housing. So please be kind if I have some newbie questions, I will pick up quickly.

Thanks a ton!

Tim

 

[alldodge]

HI All,

I just bought an older Webbcraft 18V with the Mercruiser 228 V8 305 Engine and what I can only assume is a MC1 Outdrive. My power trim works down, but is very slow on up and won't go up as far as a trailering position. Once it gets to a certain point the Trim motor keeps running but it will not raise any more. The pump appears to be a prestolite and has the numbers 74436A14 on it. I am not able to find any hits on the web for this part number, but I am for 74436A9, are those two parts interchangeable? What I am wondering is should I be looking to the motor or the rams for this problem? Are any pictures needed?

On a side note, I'm new to owning a boat but mechanically inclined (do my own car repairs, not afraid of soldering, can rebuild carbs/Work on motors etc) beyond this trim problem I'm looking to replace the impeller in the lower gear housing. So please be kind if I have some newbie questions, I will pick up quickly.

Thanks a ton!

Tim

Howdy Tim we were all new once

Need to have your post in the Mercruiser section, maybe a Moderator will move it for ya

Your question, sure could use your engine year at the least. Without it I to am unable to find the A14 pump. The A9 is a good number and will work. Need to find out if its the pump or the trim cylinders. In many cases its the cylinders that are leaking internally.

 

[THenning]

Thanks for the reply! Boat year is 1978, I'm assuming motor is of the same year. Is there a simple test to find out which is which? Pump or Cylinders?

 

[alldodge]

Thanks for the reply! Boat year is 1978, I'm assuming motor is of the same year. Is there a simple test to find out which is which? Pump or Cylinders?

Easy, sorry but no. It all takes time and testing. I would suggest first flush the trim system out and put fresh 10w30 motor oil in. If it does not help you need to get into the items. Here is the manual for your system
http://www.boatfix.com/merc/servmanl/6/6c5r3.pdf

 

[THenning]

Thank you so much for that manual! This boat came missing a lot of documentation, I know my way around a GM 305, but not a trim system (yet). Here's crossing my fingers that it's something simpler. Thanks again!

 

[biggjimm]

this is a link I received from someone about my '76 trim unit. Maybe it'll help. Is your fluid level full? I'd try the flush & fill first also. Good luck. Jim.

http://forums.iboats.com/filedata/fetch?id=10006830

 

[achris]

this is a link I received from someone about my '76 trim unit. Maybe it'll help. Is your fluid level full? I'd try the flush & fill first also. Good luck. Jim.

http://forums.iboats.com/filedata/fetch?id=10006830

That document is out of a seloc or clymer manual. Treat it with the utmost suspicion...

Best place to find the proper Merc documentation is the proper Merc manual, HERE.

Chris.....

 

[Bondo]

Once it gets to a certain point the Trim motor keeps running but it will not raise any more.

Ayuh,.... Welcome Aboard,.... Sounds like it's low on oil,....

Top it off, 'n try it,.....

 

[biggjimm]

That document is out of a seloc or clymer manual. Treat it with the utmost suspicion...

Best place to find the proper Merc documentation is the proper Merc manual, HERE.

Chris.....

Ton the download page it says mercruiser power tilt manual & I thought it was a merc' manual but now reading it again I guess it just means it's for mercruisers trim pumps & not necessarily from mercruiser. Never fooled with seloc but I know clymers have been known to contain misinformation. Thanks.

 

[THenning]

Thanks Everyone. This has been a huge help. Working through the list!

 

[THenning]

And it works! Had to bleed the line. There is a small leak on one of the high pressure lines coming out of the motor, VERY VERY minimal, but I guess I will have to top it off once or twice a summer. Thanks again!