Mercruiser lift cyl replacement

crazy charlie

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I will need to replace 1 of my lift cylinders or at least rebuild the one I have.What is the first step to removing it re: the fluid and pressure inside it.Charlie
 

FreeBeeTony

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Re: Mercruiser lift cyl replacement

Does it have a leak? If it does, the pressure shouldn't be a problem. If not, I would remove it from the O/D and I would think that would remove any pressure from the cylinder. I purchased a rebuild kit from these guys ....took less than 1 hour and it was like new.
 

crazy charlie

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Re: Mercruiser lift cyl replacement

Its not leaking ,but a few retaining rings and clip has come loose and sliding on the arm.There seems to be something pushing them off like corrosion from the inside.Any special tools for the rebuild????Charlie
 

FreeBeeTony

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Re: Mercruiser lift cyl replacement

Nope......no special tools, but I did have to cut off the end of the old cylinder to get one of the parts out. I am going to do my other cylinder over the winter.
 

Bondo

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Re: Mercruiser lift cyl replacement

If it's Not Pumping, The Only Pressure is the Weight of the drive.............<br />In the Down position, There's No Pressure........<br /><br />Used rams from freshwater can be found on ebay.......<br />For Less than the price of Parts.........
 

elpaso

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Jun 27, 2003
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Re: Mercruiser lift cyl replacement

You did not say what year - what drive ?<br />But all Merc cylinders are basically the same. You problem is a common problem - especially in salt water. <br />The seal-wiper-and lock ring groves in end cap have corroded away. These seals are what you see on rams. <br />You have to replace the cylinder end caps and seals.<br /><br />Lower outdrive - place a bucket or oil soak cloths under hydraulic oil manifold - ( where stainless oil lines enter outdrive) remove oil lines at manifold. ( will leak about a cup of oil) remove cylinder. On work bench, lock base of cylinder in a shop vise. Loosen end cap with big pipe wrench - set end of cylinder in a bucket - with 40 lbs. of air pressure - blow through rear oil line - ram-end cap- internal parts - and oil will blow into bucket. Clean everything - and keep clean. <br /><br />Buy - end cap - cap wiper, seal and lock ring kit - and cylinder internal o ring kit. Install instructions will be in cap kit. <br /><br />Pay attention to how parts come out of cylinder. Remember when working with cylinder - air pressure in either oil line will move anything in cylinder any direction easily. <br /><br />Install cylinder - fill with oil - run up and down 4-5 times - cylinders will self bleed. <br /><br />If one end cap is corroded, the other one is right behind it ?<br />Take the end cap with you to parts man - there are different diameter caps over the years. Put zinks on rams to stop corrosion problem.<br /><br />If seals have been leaking oil - water may be in pump ?<br />Merc says use a special merc spanner wrench on cap -it is worthless. Protect pipe wrench jaws with a piece of leather when installing cap.
 

ziggy

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Jun 30, 2004
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Re: Mercruiser lift cyl replacement

hi charlie, i just did one of my tubes a bit ago. i would get a service manual. between the pics and being carefull you'll get the parts back in right. i don't know about all cyl. being the same. seems like when i got my parts some of the trim tubes ya just replace as a unit, depending on year. mine is a old merc I drive. they were rebuildable. they had a master rebuild kit and a cheaper just plane rebuild kit. i used that for about $20. wasn't hard. no excessive pressure, no special tools other than the big pipe wrench with extra 3' of pipe for extra leverage. also, my old merc I drive is not self bleeding. that was the best part of the service manual to me, proper bleeding procedure. for sure when bleeding keep the resivour topped off or you'll get low, suck air and have to do it all over again.
 

crazy charlie

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Re: Mercruiser lift cyl replacement

Thanks for the info guys,sounds like I can tackle the repair myself when she comes out of the water next month.I may keep an eye on ebay to see if i can just get a new one in the mean time.This would be a good time to change the ss lines too.Im tired of those sharp little splinters stabbing my hands.I dont think they are all the same though.These surely look different from my last alpha setup.Charlie
 

FreeBeeTony

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May 15, 2002
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Re: Mercruiser lift cyl replacement

If you decide to purchase the kit from the guys I recommended, they are very helpful. They offer tips where they can. You definatly need a manual for the pics alone...........
 

crazy charlie

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May 22, 2003
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5,602
Re: Mercruiser lift cyl replacement

Thanks Tony,if I do the overhaul,I will surely need some help.I may try it over the winter just to attempt to learn it even if i get a replacement.I had Tom from Bennett trim tabs walk me through rebuilding a trim tab piston and it was easier than I expected.Charlie
 
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