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marc05

New member
Good day all, I tried searching and could not seem to come across my answers, appologies if this topic has been covered
I have purchased a boat that had a 454 / 350 swapped, the original 454 cracked a block apparently because it was not winterized properly. So the 350 was swapped in, and the install is about 95%, and then I bought it because the guy was leaving town. I did not discover it originally had a 454 until after I got it home.. So thats the back story.
Now the question. I have what looks like the original 454 oil/ps cooler and it seems there is no place for the oil ports. I have this spare hose that looks like one of the hoses for the oil cooler but can not seem to see where it goes. I tried looking for photos of line routing etc and could not.

So my question is. With the 454 oil/ps cooler, what do I do with the oil cooler ports off of the cooler? I would just run the oil through it for the 350, but unsure what lines to run and where to connect these.
Perhaps I just block off the ports?
If someone can direct me a bit would be very helpful. It is I think one of the last puzzle pieces I need to get it running. Thanks!
 
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marc05 said:
..................

Now the question. I have what looks like the original 454 oil/ps cooler and it seems there is no place for the oil ports. I have this spare hose that looks like one of the hoses for the oil cooler but can not seem to see where it goes. I tried looking for photos of line routing etc and could not.

So my question is. With the 454 oil/ps cooler, what do I do with the oil cooler ports off of the cooler? I would just run the oil through it for the 350, but unsure what lines to run and where to connect these.
Perhaps I just block off the ports?
If someone can direct me a bit would be very helpful. It is I think one of the last puzzle pieces I need to get it running. Thanks!
Click to expand...

If this is a cooler for the Power Assist steering pump oil..........
https://www.mrcool.us/99356a2-mercruiser-power-steering-cooler.html?gclid=CjwKCAjw-7LrBRB6EiwAhh1yXwmdWtoA44m-J_NImOHgBrpQaJcBnEjFso5m7bkgTkbbKbrV_5QlTRoClZAQAvD_BwE
......... it will not connect to the 5.7 engine. It will install within the Power Assist steering pump's return line.

If this is a tandem style Power Assist steering and Engine oil cooler.........
https://www.mrcool.us/513536-marine-power-tandem-cooler.html?gclid=CjwKCAjw-7LrBRB6EiwAhh1yX4YkUIomnLnmnw_Pc8qJJlCtX8iEi2mo9uwGZL6fWA1TVXArn4pr4BoCYk8QAvD_BwE
...... then you'll need to install an adapter unit that will allow the two hoses to connect to the area where the engine oil filter is located.


You can purchase an adapter unit that will allow the use of the engine oil cooler.
See this ME.com thread!

http://www.marineengine.com/boat-forum/showthread.php?421373-Oil-Cooler-before-or-after-Oil-Filter
hda-205_w_ml.jpg





Also keep in mind that the 454 engine's final gear reduction (drive ratio) will not be the same as what the 350 engine will require.




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5.7 merc does not have an oil cooler.

I would cut my losses on this SB engine and find a BB to put back. I guarantee that you will be extremely unhappy with the performance.
 
Thanks for the feedback.
Can I block off the ports for the oil cooler portion if the 5.7 does not require the oil to be cooled? Or do I replace the cooler with the appropriate power steering only one for the 5.7
Thanks
 
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Oil Cooler.jpg
The boat is a 1995 Glastron SSV249, I belive it is 25'

I know you suggest scrapping this idea. However it is 99% ready to go. I will at least need to get the motor running and the boat in the water if I want to entertain selling the 350 and replacing with a BB. Scrapping the 350 is not an option at this point.
..I have edited my above post for better clarity
 
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A good strong and healthy 5.7L may be a bit under-powered, but it should work in a 24 foot boat!

this one is listed with a 5.7L.


68777416_614.jpg
 
You don't need the oil cooler to run the boat.
You are referring to two different bits of apparatus. The 454 has an engine oil cooler AND a power steering fluid cooler. Again, you don't have to have either one to run the boat. If the coolers are plumbed into the hoses already then you can just leave the oil lines off. On the power steering, the oil cooler is in the low pressure return line that goes from the steering actuator to the "canned ham" reservoir. Use fuel hose here to bypass the oil cooler, or plumb it up if it's present and you feel more comfortable doing so.
For the engine oil cooler, I personally don't think these do much effective and my vote is to delete it altogether. The best reason to keep it however, is that the access to the oil filter may be impossible with the engine in place. If you must have it, the oil lines come off a spin-on adapter thingy on the place where you'd normally put a oil filter. There are two mongo hydraulic hoses coming off it. One goes to the remote oil filter housing and the other to one of the ports on the oil cooler (doesnt really matter which. I cant recall if the engine oil cooler has two of the same ports or what but the length of the hose will tell you hahaha). The other outlet of the engine oil cooler goes....guess where? To the oil filter adapter!
So, hope this helps. good luck with it and never never never buy a boat that you don't sea trial before handing over any money. If you don't know what to look for. pay the couple hundy to a qualified marine surveyor and they will tell you the truth.
As Chris says, this bleach bottle will barely get out of it's own way with that engine. However, the kind of people who buy these are more concerned with bikinis per mile than miles per hour.
99% ready...as if.
 
Apologies I am not being clear enough I don't think.

The apparatus I am referring to that is in my boat, is a Power steering/Engine oil cooler combination, the exact same device that is in the photo I provided above. So I am referring to the same physical device, however it provides 2 functions.
Currently the power steering portion is plumbed in.
The engine oil half is not plumbed in...
Currently also, the oil filter is remote and not located at the back of the block.
Is the Engine oil/ps cooler apparatus ok if I only have the PS portion plumbed? Or do you recommend I just remove the cooler altogether and plumb the power steering directly?
Thanks for the help and understand all!
 
marc05 said:
................

The apparatus I am referring to that is in my boat, is a Power steering/Engine oil cooler combination, the exact same device that is in the photo I provided above. So I am referring to the same physical device, however it provides 2 functions.
Yes, some call it a tandem oil cooler! When all lines are connected, it cools both Power Assist steering fluid and engine oil.

Currently the power steering portion is plumbed in.
The engine oil half is not plumbed in...
Understood.

Currently also, the oil filter is remote and not located at the back of the block.
That is a plus!

Options:

...replace the remote filter cartridge base with something like a Hayden unit that allows for an engine oil cooler in/out connection.
These new hoses would run to the tandem oil cooler and back to the Hayden unit.

...replace the remote filter base with a Hayden unit that offers thermostatically controlled engine-oil-to-cooler-and-back.
Again, these new hoses would run to the tandem oil cooler and back to the thermostatically controlled Hayden unit.

...abandon the idea altogether, and run the tandem cooler with only the PA steering fluid connected.
Plug the two remaining open ports.

If you end up using the Hayden style remote oil filter base, note that the hoses from the engine's adapter are directional.
In other words....... the engine oil enters the outside of the filter media, and returns to the engine's oiling system from within the interior of the filter media.

As for the tandem oil cooler ports themselves, these connections are not necessarily directional.


Is the Engine oil/ps cooler apparatus ok if I only have the PS portion plumbed?
Yes, absolutely.
I would leave the PA steering system oil plumbed to the cooler..... it's free oil cooling.
Keep the oil within a cool range rather than a hot range.

Or do you recommend I just remove the cooler altogether and plumb the power steering directly?
In my opinion, there is no need to remove it.
Simply leave the Power Assist pump's low pressure return hoses connected, and perhaps plug the ports for the engine oil lines.

Thanks for the help and understand all!
Click to expand...


Keep your chin up..... don't be intimidated by any grumpy attitudes.




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I would pull it out and not have to worry about another point of failure. Run full synthetic power steering fluid if you're worried about the heat getting to it; it won't boil off. The only reason it gets hot is that the pump sits near a warm engine and the friction of running thru the pump and steering gear builds some heat. Unlike a car, there's not a steady stream of fresh air swirling around to take some of that heat away, thus Mercruiser's engineering solution. Bazillions of boats out there with no cooler for either the PS or engine oil. Your call tho.
 
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marc05 said:
Apologies I am not being clear enough I don't think.

The apparatus I am referring to that is in my boat, is a Power steering/Engine oil cooler combination, the exact same device that is in the photo I provided above. So I am referring to the same physical device, however it provides 2 functions.
Currently the power steering portion is plumbed in.
The engine oil half is not plumbed in...
Currently also, the oil filter is remote and not located at the back of the block.
Is the Engine oil/ps cooler apparatus ok if I only have the PS portion plumbed? Or do you recommend I just remove the cooler altogether and plumb the power steering directly?
Thanks for the help and understand all!
Click to expand...

You can just use the Power steering side. You can leave the other ports open or plug them, its up to you.
 
Ha ha ha well fortunately the advice here is free of charge. Some of it isn't worth even that much tho...caveat emptor.
 
Never before have I heard caveat emptor being used as warning for something that is/was free!

As I said..... Keep your chin up..... don't be intimidated by any grumpy attitudes.
 
post count increased! Yeh I know some folks get a little squirrelly when I go all metaphysical. Hey and my post count just went up tooo! Wooohoo! Not grumpy, just fed up.
 
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A 5.7 with no specs as to power will be a dissapointment.
A 25 ft boat with a 5.7 and a bravo one will be a dog.
If it had(s) as bravo 2 then that will improve the perfomance.

The 65 hp loss (based on a 260hp sb vs a 325 hp bb) and of course the large touque loss will be very noticable.

And as clearly domenstrated in the first couple post count replies, a clear lack of Mercruiser product knowledge was displayed again as seen over and over and over again.

Post count, peat and repeat....and it has nothing to do with getting old.....
 
kghost said:
A 5.7 with no specs as to power will be a dissapointment.
A 25 ft boat with a 5.7 and a bravo one will be a dog.
If it had(s) as bravo 2 then that will improve the perfomance.

The 65 hp loss (based on a 260hp sb vs a 325 hp bb) and of course the large touque loss will be very noticable.

And as clearly domenstrated in the first couple post count replies, a clear lack of Mercruiser product knowledge was displayed again as seen over and over and over again.

Post count, peat and repeat....and it has nothing to do with getting old.....
Click to expand...
Thanks for the input. You are completly correct, I know next to nothing about mercruisers and this is why I am here.
Unfortunately for you, if you are floating around forums and expect experts on the subject only, I can see why you are fed up.
Please accept my sincere appologies for inconveniencing you with my elementary questions.
However.. I would like to add. I am not actually looking for opinions about 5.7 hp etc. I am simply looking for technical advice for the questions I did ask. So although your time and input is appreciated, it was something I was not asking for.
 
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FYI
The off comments were not directed towards you...
That individual knows.

As far as your situation,
You can move forward but dont expect great performance.
There was a good reason that boat was out fitted with a 454.

Typically when a larger boat is out fitted with a small block it is a cost issue which allows the boat to be more affordable.

If a small block is used in combo with a bravo 2 (which uses a very large diameter prop) offsets the power discrepancy byway of the gear ratio and large prop moving more water...

So if you get this running and you find it to be a poor performer you might consider finding a bravo 2 outdrive.
Direct replacement. Just need correct ratio and prop size.
 
Seriously for what its worth, I dont know if I will ever expect to even get on a plane... I live near Chester NS. Mostly sail boats roam around here. I will be mooring the boat at a marina, And trolling out to the island beaches on the weekends, treating the marina and boat more like a RV at a campground than something I will be putting miles on. Performance is the last thing I am looking for. It will likely never leave mahone bay for the rest of its life.
Thanks for the clarity. I will keep an eye out for a bravo 2, appreciate that bit of info.
Also.. if/when I do get this running, I will gladly come back with performance reviews and you can all say Itoadaso!
Even tho I have no doubts you guys are all correct... At this point it is not the concern. I am still on step 1. Get it running.
 
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Got it!
If thats all you expect....you will have a great time!

Just make sure to reassemble all the right way and no short cuts or work arounds.

Remember, if you redo all as if it was done by the factory and you have a problem, any experienced tech will be able to repair it.
Try to use only OEM parts and keep all serial numbers easily accessable for parts needs
 
marc05 said:
Seriously for what its worth, I dont know if I will ever expect to even get on a plane... I live near Chester NS. Mostly sail boats roam around here. I will be mooring the boat at a marina, and trolling out to the island beaches on the weekends, treating the marina and boat more like a RV at a campground than something I will be putting miles on.
Performance is the last thing I am looking for. It will likely never leave mahone bay for the rest of its life.
Click to expand...

You have no doubt factored that in from the beginning, of which makes your SBC decision all the more reasonable for you.

Good luck and have fun.


As for post counts, I don't understand why a few members are so concerned and/or bothered about post counts!
Post counts do not represent one's expertise, experience, authority, etc. They simply indicate one's participation in the forum.
I would be embarrassed if I were to repeatedly mention post counts as though I was threatened by them.




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I had an old Bayliner 28 footer with a SBC and a Volvo-Penta outdrive. It cruised nicely at 25 mph or so, turning 3,500 rpm, and it had to be heavier than yours.

Even with the Bravo One, you should be fine with the correct prop--and that's the key here; you need the right prop.

Jeff

PS: Bayliner sold a zillion 28 foot boats with SBC power. I rode in one that hit 40 mph.
 
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