Zeus Pod Transmission Coolers

D

Dunigan

Member
Nov 21, 2018
64
Boat Info
2013 Sabre 42
Engines
twin cummins qsb 6.7
The zeus pods on my 2013 have 550 hours. I have been told to replace the transmission coolers (two on each pod) due to age. If they fail and allow seawater to mix with the hydraulic fluid, it could be bad for the transmission or steering depending on which cooler fails. Mercury has no position on this matter. Have any Zeus owners replaced their coolers as a preventative measure? If so, at what age/hours? Have any Zeus owners had theirs fail and what damage resulted? Thanks in advance.
 
Pretty sure I replaced mine when I bought the boat last year. Will have to wait til tonight to check my records.
I was low hrs, 275ish, but 10 yrs old. If memory serves, ,in the scheme of things they weren't that expensive.
 
Thanks, Shaps. If you find out tonight that you did replace them, please let me know if it was for 'preventative' purposes. I agree that it isn't that expensive...about 2800 in parts plus labor. Beats the heck out of a failure and the resultant damage. A well regarded Zeus technician in Florida recommends replacing every 5 years.
 
My transmission coolers were replaced as part of the pod & transmission service I did when I bought the boat.

Dunigan said:
...Beats the heck out of a failure and the resultant damage. A well regarded Zeus technician in Florida recommends replacing every 5 years.
Click to expand...
Sounds like good advice too.
 
My starboard oil cooler leaked oil externally into the water back in 2017. The new cooler was just under $1,000 and an hour labor at most. I’m going to replace port this season for proactive PM.
 
Hours when the failure occurred, hours now? So your cooler leaked externally? Interesting. No damage to trans or steering? Did the tech who replaced it have any opinions on how long they last? Thanks in advance.
 
Dunigan said:
The zeus pods on my 2013 have 550 hours. I have been told to replace the transmission coolers (two on each pod) due to age. If they fail and allow seawater to mix with the hydraulic fluid, it could be bad for the transmission or steering depending on which cooler fails. Mercury has no position on this matter. Have any Zeus owners replaced their coolers as a preventative measure? If so, at what age/hours? Have any Zeus owners had theirs fail and what damage resulted? Thanks in advance.
Click to expand...

Where are you located? There is a company in Jupiter Florida, Seibert Yacht Management that does a lot of Sabre and Zeus work (as well as IPS). The owner Jay Seibert hosts the Sabre and Back Cove Tech group on Facebook. They done a lot of work with Zeus and not too long ago posted a mod redirecting the exhaust to improve cooling in the Zeus pods. You might reach out as they do extensive travel on the East Coast.

As full disclosure, I have not done any business with him, but have read a number of his postings on FB, as well as had questions answered by him.
 
I have spoken with Jay several times and watch his Facebook sites. He is truly Dr Zeus!
Many thanks!
 
Chesapeake Bay. In my earlier post where I referenced a tech who advised replacing the coolers every five years, I was talking about Jay.
 
Henry Boyd said:
... They done a lot of work with Zeus and not too long ago posted a mod redirecting the exhaust to improve cooling in the Zeus pods.
Click to expand...

@Henry Boyd
Any chance you can post that mod (or a link to it)
That facebook group is moderated. I've requested to join.
Thanks!
 
Shaps said:
@Henry Boyd
Any chance you can post that mod (or a link to it)
That facebook group is moderated. I've requested to join.
Thanks!
Click to expand...

Sorry, I posted the originator’s company & name because the group he posted in is private. You might contact them directly. I’ll try and copy cut/repaste to here.
 
Henry, Shaps: I also follow Jay Siebert on his Sabre and Back Cove Yacht Tech Group Facebook site. I 'think' Henry is referring to a discussion on that site dealing with steering actuator heat issues where Jay made the following comment (Henry, please correct me if I am wrong here):

"The failure is caused by heat from the exhaust running through the actuator. I’m going to strongly recommend to all zeus owners to install a through hull exhaust fitting and completely bypass the exhaust going through the drive. This will prevent the seal failure entirely. May be louder, but no heat failure of the seals. The seals were very burnt in the area of the exhaust, proving that’s what causes it."

Jay has worked on Zeus units since the beginning and has seen all generations of the zeus pod. He describes the issue as follows:

"it’s the exhaust gas temp which is the issue. It all depends on how the water flows through the exhaust pipes and actuator. There have been many recommendations on hose routing and bypass hose/muffler size over the years. We’ve had many experiences with the early 40’s with water flow and ECM parameters based on exhaust temp and flow characteristics. Also changes on Early 42’ Zeus exhaust sizes. The biggest problem is how the water flows through the pipes. If the water only flows in one direction “like a water slide at the amusement park” or one side of the pipes, you get hot spots in the other sections. In addition, this doesn’t account for weak impellers or a restriction in the water supply. At this point there is no “buffer” if EGT gets too high. Now you end up with burnt seals."

In short, Jay's recommendation to route the exhaust away from the steering actuator, while somewhat radical, comes from years of frustration with this issue. I don't know if he has actually done this on any boats he services.

I am currently trying to get Mercury to consider improving these actuator seals to withstand greater heat. I have tried to find out what material they use (and therefore what heat resistance) but was stopped by 'the lawyers'. Nevertheless, I am still trying through other channels. I don't hold out much hope but you never know.
 
Dunigan said:
Henry, Shaps: I also follow Jay Siebert on his Sabre and Back Cove Yacht Tech Group Facebook site. I 'think' Henry is referring to a discussion on that site dealing with steering actuator heat issues where Jay made the following comment (Henry, please correct me if I am wrong here):

"The failure is caused by heat from the exhaust running through the actuator. I’m going to strongly recommend to all zeus owners to install a through hull exhaust fitting and completely bypass the exhaust going through the drive. This will prevent the seal failure entirely. May be louder, but no heat failure of the seals. The seals were very burnt in the area of the exhaust, proving that’s what causes it."

Jay has worked on Zeus units since the beginning and has seen all generations of the zeus pod. He describes the issue as follows:

"it’s the exhaust gas temp which is the issue. It all depends on how the water flows through the exhaust pipes and actuator. There have been many recommendations on hose routing and bypass hose/muffler size over the years. We’ve had many experiences with the early 40’s with water flow and ECM parameters based on exhaust temp and flow characteristics. Also changes on Early 42’ Zeus exhaust sizes. The biggest problem is how the water flows through the pipes. If the water only flows in one direction “like a water slide at the amusement park” or one side of the pipes, you get hot spots in the other sections. In addition, this doesn’t account for weak impellers or a restriction in the water supply. At this point there is no “buffer” if EGT gets too high. Now you end up with burnt seals."

In short, Jay's recommendation to route the exhaust away from the steering actuator, while somewhat radical, comes from years of frustration with this issue. I don't know if he has actually done this on any boats he services.

I am currently trying to get Mercury to consider improving these actuator seals to withstand greater heat. I have tried to find out what material they use (and therefore what heat resistance) but was stopped by 'the lawyers'. Nevertheless, I am still trying through other channels. I don't hold out much hope but you never know.
Click to expand...

That's the one I was referring to. I tried to find this posting while sitting at the DR.s this am waiting for my appointments and couldn't find it. Glad I checked here before going back to searching. I will point out the Volvos also take in cooling water and discharge exhaust gas / hot water via the pods structure and do not have these issues. I did query whether Volvos were equally at risk and the response was an honest "don't know".
 
Volvo uses electric steering so no hydraulics and maybe no seals but I am not nearly as versed in IPS. Their exhaust, I think, goes directly into the lower unit as opposed to into the steering actuator (Zeus). It also does a kind of 'turn' before it heads down into the lower unit which may create better mixing and heat distribution. Just my thoughts.
 
Why not add a designated water line to the Zeus exhaust tube? T off right after the raw water pump, before water is warmed by after cooler and heat exchanger?
 
Might work but well beyond my technical skills. In fact, the QSB6.7 Zeus pods take some exhaust water via a bypass to cool the trans coolers. That water is not returned to the main exhaust tubes. Perhaps it could be. The QSM design does return it to the exhaust tubes.
 
Dunigan said:
Volvo uses electric steering so no hydraulics and maybe no seals but I am not nearly as versed in IPS. Their exhaust, I think, goes directly into the lower unit as opposed to into the steering actuator (Zeus). It also does a kind of 'turn' before it heads down into the lower unit which may create better mixing and heat distribution. Just my thoughts.
Click to expand...

Actually without seeing it you described it pretty accurately, and forced me to look closer at mine and do some research.

Right on the steering, in my ignorance of Zeus I didn’t realize you guys didn’t have electric servo control. The size of the Volvo head unit is dramatically smaller than the Zeus and Kim guessing I now know why.

The cooling water is drawn essentially from a “through hull” in the base of the head unit casing and I assume circulated through the head unit to cool the gearing because of the location of the outlet that goes forward to the engine. That said the strainer for the raw cooling water is located on the engine, and given the Volvo folks seem more than meticulous, it also makes sense that the water flow could only be doing nominal cooling of the pod gearing. It would also explain why Volvo is so anal about annual lube changes.

The aft section of the IPS lower unit appears to be hollow (with the obvious exception of the prop’s counter rotation gear housing) and opens behind the prop gear casing. This hollow section forms basically a large L shaped exhaust outlet similar to the traditional underwater exhaust nozzle. The big difference being the exhaust gas is always injected into the prop wash and the traditional exhaust is fixed facing aft.

While it would seem that gear cooling is not exacerbated by exhaust gas as it appears to be with Zeus, my sterndrive experience suggests Volvo gear cooling also leaves a bit to be desired.
 
Question to Zeus guys. Zeus uses aluminum anodes. So do I use aluminum or zinc anodes on the transom and hydraulic swim platform? Salt water
 
Waiting on bonding diagram from Searay. I would think it wouldn’t matter if Zeus and vessel are not bonded together.
 
Not a SeaRay owner so I don't have swim platform anodes. The transom anode on my Sabre (Chesapeake Bay) is aluminum. Works for brackish to salt water environs.
 
You must log in or register to reply here.

Forum statistics

Threads
113,118
Messages
1,426,467
Members
61,033
Latest member
SeaMonster8
Back
Top