OMC Cobra Volvo Penta SX Tilt Trim Cylinder Rebuild

Finally a complete how-to for the OMC trim tilt cylinders. I used part # 0985060 for the build, along with 4 - 5/16 x 1/16 o-rings (purchased separately from your local hardware store).

[@Luigi-pk8mk]

Hey Mike thanks for the vid, after 35 years one of my trim rams started leaking, I had bought a couple of spares some years back because my boat is all salt water use, so I didn't think the old one would come apart. I was able to get the cylinder cap off pretty easily (surprise) and the end piece that is screwed onto the rod came off with a little brute force but didn't have to use heat. The only thing I did slightly different was to make a guide out of an alu can following the instructions that came with the kit, I folded over the tabs as shown in the instructions and taped them to the housing to keep the alu from sliding inside while sliding the piston in well lubed up with T&T fluid. I used blue loctite on the threads for the end piece and used a bit of triple guard grease on the threads for the cylinder cap in case I ever have to take it apart again. I think it costs about $500 to get these done at a shop, a few hrs and $50 for a kit, is a great deal!

[@stainboy07]

Hey Mike, I have watched a ton of your videos and they're all awesome, I just rebuilt my cylinders as per your guidance and they are both working great now. No drift, it's awesome, Thanks !!

[@floridagirl386]

What is drift?

[@stainboy07]

@@floridagirl386 drift is essentially when you have your lower unit trimmed up to a certain point it will slowly fall lower and lower. You’ll have to keep trimming up the lower unit cause it “drifts” down. Which means there is not a perfect seal throughout the trim/tilt motor and/or cylinders.

[@floridagirl386]

@stainboy07 gotcha! Thankyou for answering, wasn't really expecting that.

[@floridagirl386]

@@stainboy07 brand new yamaha 50 under 2 years old started doing that. So that's what it's called

[@mrbusy56]

Great video. Just rebuilt my DPSM cylinders. Saved me hundreds by not getting the professionals in, thanks

[@michaelromer2016]

Mr Busy Glad you liked the rebuild video!

[@georgedesiderio9914]

I have a DP-SM as well. The cylinders are slightly different. No long hose fitment-both hoses attach near rear of cylinder. Also the eye head is part if the piston rod and the bottom portion with the three seal unscrews from the rod. I think my cylinder leak may be traceable to some prior work not done properly. The three bottom seals on mine were arranged with the two split seals sitting above the continuous o-ring unlike your where the continuous o-ring is sandwiched between the two split rings. I can fully understand why the arrangement on mine can leak. Good video!

[@floridagirl386]

I wish someone did an in detail video like this for mercruiser alpha 1 (gen 1). This might still help so thankyou

[@JEL279]

Hello Michael, I have watched all of your videos on trim tilt, very helpful! However, I am unsure on how to refill the entire system with new hydraulic fluid and bleed all of the air out of the system. I have read a couple of your comments explaining how to do it but I still don’t fully understand. If able could you post a video? I have also read through the service manual with no success on how to accomplish this task. Josh

[@michaelromer2016]

Hey Josh! The process is not that bad. I'll tell you the trick. First and foremost you want to have both cylinders completely filled with fluid. I would have the stern drive all the way down (as if it is in the water) and attach the lines (after you have the cylinder filled). This way your stern drive doesn't have to pivot very much. From there, attach your lines and start working on the pump. You undo the red cap and fill the reservoir up until the point it drips out. You will be tempted to overfill it. Doing so will cause an explosion, which I have seen first hand. As you are bleeding the system, you want to have a battery charger hooked up as it may take a while to get all the air out. Another thing to note is you can only go completely up and down about ~10 times before you start popping the breaker (overheating the pump). You need to have someone watch the stern drive as you are raising it all the way up and down. When they say it isn't moving, stop, and check the fluid level. Once a full up and down interrelation is completed, stop and refill the reservoir. If full, just open the red cap and listen for the air coming out. I recommend checking for air on the full down position (stern drive is all the way down).

[@JEL279]

Fantastic! I’ll do that! In your other videos I noticed that you had a a book or technical guide manual in some of the background shots that you were referring to. Can you tell me the title of that book and or where I can find it? Josh

[@michaelromer2016]

Here you go: sunbirdcorsair.files.wordpress.com/2011/03/1986_-_1998_omc_sterndrive_man.pdf

[@russellcampbell76]

@@michaelromer2016 "First and foremost you want to have both cylinders completely filled with fluid. I would have the stern drive all the way down (as if it is in the water) and attach the lines (after you have the cylinder filled)" That skips a lot. Based on what you're saying, I'm assuming the cylinders are on the outdrive (could they also be filled before reattachment?). How do we fill them? I'm thinking some sort of small hose to feed in fluid as the (as yet unattached) hydraulic fluid supply hoses do. I'm not working on this exact outdrive, but certainly the bleeding process is going to be similar. Thanks.

[@lbiffin]

Hey, great video. I’m planning on rebuilding my cylinders tonight but my only question is when and where do you replace the fluid and do you have a video for how to bleed that System properly? Thanks in advance.

[@elbuenamigo3112]

Hi friend, I have a boat with an OMC outdriver with a 5.0 engine, but I would like to know where I can buy these seals. My cylinders are leaking oil, please, because I can't find them no matter how much I look for them. Thank you.

[@adsbadsb9488]

Michael can you tell how to bleed the system please. Usually those had the pump motor that looked like a coffee can. No external reservoir. How do you get enough fluid inthem.

[@longboarder211]

Great video... I started the work but I can't remove the flare nuts for the hoses. 1 removed too easy but now the flare nut wrench has stripped the other three and I'm gonna have to pull the out drive to replace the hoses... I absolutely hate this boat at this point. any recommendations for pulling the leg and getting this done fast an efficiently...

[@michaelromer2016]

longboarder211 Sorry to hear that! Depending on the age of the boat, you get to perform some much needed maintenance now. Take the stern drive off first, then make sure check your engine alignment is perfect. If your alignment is way off, install a new gimball bearing and align the engine. Also, remove both bellows, this will allow for easy access to your hydraulic hoses. Use penetrating oil on the stuck flare, then wait 5 mintues, then try the flare again. If the hose is for sure, never being used again, cut the hose close to the flare and pound on a deep socket and remove it that way. There's always vise grips too. The connection for the other end of the hose is right above the bellows and are easy to get to with the bellows off. Remember to use penetrating oil since it seems you have some prior flare issues. So for the issue at hand, remove the stern drive, remove upper and lower bellows, install new hose. The hose can be bought for as little as $58 (probably should replaced both). The bellows are cheap too. Don't be too frustrated, if all goes well, you can fix this for less than $200 yourself.

[@longboarder211]

Michael Romer thank... ya I’m 33k into just repairs on this boat... literally living the acronym and all the money I saved from deployments flushed into the ocean. I’m gonna pull the drive and replace the hoses so I’m gonna cut them, I ordered the new ones and fingers crossed it’s done and I can finally sell this thing

[@michaelromer2016]

Oh wow, that's a lot of $. Don't forget to watch this video again on how-to bleed the hydraulic system after you get everything replaced. Air in the system is a pain to get out.

[@jeffwhite548]

Will those rods have any trim cylinder oil on them in the water? I have chemtrail leaks in the water but I have no idea where they are coming from. I just rebuilt the trim cylinders on the SX-M drive. What else should I check?

[@michaelromer2016]

They should not be leaking and even if they were, it wouldn’t be enough to see. Check your outdrive oil level. You maybe leaking oil near the prop.

[@globaltraders1338]

I recently purchased a 1990 195 corsica with the 5.0 v8 in it from a good friend..it hasn't ran in 4 years, but they had some trouble with a fuel issues right before it got parked for several years...if they engine is seized. Do you think marvel oil is worth a shot to get it to turn over mixed in with oil change...

[@boephco]

What is the process for putting the new fluid in or bleeding the lines? Should the trim fluid be put in before putting the end piece on; doesn't seem practical otherwise it would come out?

[@michaelromer2016]

Boyd, after replacing all the seals you can add fluid to each hole (2 on each cylinder) until all the air bubbles stop. It's easiest to do right before you attach the hydraulic lines, as the fluid will get all over the place otherwise. Check this new video out too kzbin.info/www/bejne/iofEpWaunrOHmZI

[@jackmartin5241]

Great video very helpful thanks

[@michaelromer2016]

Very welcome!

[@sony9675]

on the other end of the hydraulic line, the transom side, is there a 5/16 oring on that side aswell as the cylinder side?

[@michaelromer2016]

Correct

[@awaterworld8760]

at about the 17 min mark you explain taking off the cylinder cap so the cylinder retaining cap can come off, you mention just put a 3/4 socket and unscrew as the plunger part with spings will not come off,, wrong, all that happens when I try that is the section with the springs turns, not the shaft or end cap?

[@michaelromer2016]

You might need to take the 3/4 bolt off and then install a few nuts to lock up the bolt so you can get the caps off. Please subscribe!

[@awaterworld8760]

I got it off and all back together! the 2 large stainless bolts/rods that hold cylinders on at both ends of the cylinders, you torque those nuts on each end? it seems like trying to do so really clamps the cylinders and the bushings up against the case? thanks, and I did subscibe!@@michaelromer2016

[@tanthony3895]

I have a mercruiser alpha one Gen 2 that needs the cylinders resealed. Can I simply pull the cylinder out of the housing without taking the entire cylinder off therefore using the boat to brace it so I can pull the cylinders out once I unscrew the end cap? If so do I have to release pressure on the system to be able to do that? I assume those cylinders are under hydraulic pressure even when the boat trim is not being used. It seems like it would be easiest to be able to pull the cylinders apart to put the new seals on while they are still on the boat so you don't have to put them in a bench vise. Am I correct in this assumption? please reply I really need your help and I appreciate everything you do.

[@michaelromer2016]

I've been thinking about this one for a few days. The reason I wouldn't do it on the boat is for two reasons. The lower cylinder bolt that goes through the stern drive might not be rated for the torque. Also, there are typically plastic grommets on the cylinder ends that can snap. It could work, but the risk of damaging other parts has me worried. Please hit that subscribe button. I might one day get into Mercruisers. Thanks!

[@tanthony3895]

Thanks !! Will do!

[@jacobhilbert5583]

Can you post a link to where I can but one of these kits.

[@dirkloyder1258]

How Tight do you tighten the trim cylinder shaft bolts when reassembling please let me know??!!

[@michaelromer2016]

Are you talking about the end cap on the trim cylinder? The one with four holes in it?

[@dirkloyder1258]

@@michaelromer2016 yes the bolt on the bottom that tighten the shaft!!

[@paulkocher3919]

Thanks for the great video

[@michaelromer2016]

Glad you like it! I’m working on more content and I hope it is ready soon!

[@dominicmarrara7050]

thank you very helpful

[@michaelromer2016]

Glad you liked the video

[@eagle5720]

I have my gimbal off so I want to rebuild the trim cylinder before put them back together

[@tyleranderson4608]

Hey Michael quick question. I'm in need of a trim cylinder rebuild but cannot seem to find the part number for my cylinders to know if I'm getting the right seal kit? I have a Volvo penta DP-SM 1.95 duoprop. I need the seals like you use in this video

[@michaelromer2016]

What year is your setup?

[@michaelromer2016]

crowlymarine is a good place to get the parts btw.

[@tyleranderson4608]

@@michaelromer2016 mine is a 2000 volvo penta Gsipefs engine and a VP dp-sm 1.95 duoprop outdrive

[@keysautorepair6038]

So will this cause a leak down issue.

[@grasscutter88]

I installed the outer seal backwards. Is that a problem?

[@michaelromer2016]

Yes, if installed backwards, water will enter the cylinder. You will have a critical failure in about a year.

[@grasscutter88]

@@michaelromer2016 Great. I have to take the whole thing apart again.....

[@michaelromer2016]

@@grasscutter88 sorry I had better new for you. Thanks for your comments.

[@grasscutter88]

@@michaelromer2016 It's not a big deal. Getting pretty good at taking it off and on. lol. Are there any other seals on these rams that are critical as to the direction they go? I know their was one in the middle that was so rotted out I couldn't even tell what direction it went.

[@grasscutter88]

@@michaelromer2016 I flipped the seal around. It still weeps just a wee bit out of the outer seal. I wonder what that means. Maybe a gouge in the sealing surfaces somewhere? It's still way better than it was. Before it would empty the whole reservoir out when you trimmed it down. lol

[@eagle5720]

Whats the cost of that rebuild kit

[@Jon-to6969]

How did you get your ram shafts so clean and shiny? Mine are very oxidized looking.

[@michaelromer2016]

Great question! Look for Simichrome Metal Polish. It is available in a lot of hardware stores.

[@damianwedzicki8158]

Hi what hydraulic oil I have to use

[@mrzif0013]

i have fluid on the botom of the trim cylinder arms would you advice a rebuild of the trim cylinder?

[@michaelromer2016]

Something is leaking, I'd like to say it is the seals but you need to see how far north it is dripping from. It could be from the exterior seals--closest to the inner piston rod.

[@billmadle1235]

Fantastic

[@michaelromer2016]

Thanks! Please hit that subscribe button!

[@Neriovlogs925]

Hello Michael where did you got the seal kit 0985060? Thanks

[@Neriovlogs925]

Michael last question what type is the hydraulic oil you use to refill and where do I need to pour it?

[@morsemason9031]

I like your video on the trim pump rebuild I followed it step by step and when finished the pump worked better but not as it should , It still leaks down while underway only while in forward and moving at a good speed. in your opinion do you think rebuilding the cylinders will fix this problem?

[@michaelromer2016]

Morse Mason Thanks! If you are have any kind of internal leaks, rebuild both the trim pump and cylinders at the same time. The cylinder rebuild kit costs around $60 (for both) and takes about 2 hours--start to finish. Considering the age of the OMC equipment out there, by the time you finish troubleshooting an internal leak, you could have already rebuilt both cylinders. Keep an eye out for the OMC Cobra stern drive trim tilt assembly bleeding video here in a few days--it's a must see!

[@morsemason9031]

Michael Romer I will be looking forward to seeing that video thanks for your reply

[@adsbadsb9488]

I have a picture of the kit

[@eagle5720]

I saw that part number with the seals on Amazon for $36 is that the right one?