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1) That picture sure shows cooler to filter to engine, I have always heard the other way.
2) the fittings on the stock filter head are 5/8 NPT but if you look inside the head the oil passage is restricted to about 3/8 |
I would think hotter oil would flow through the filter better.
I don’t typically go with the old way thinking of filtering first in case you had a failure the trash doesn’t get into the cooler. If you have a failure no matter where the filter is the cooler and lines should be replaced. |
Originally Posted by Unlimited jd
(Post 4857815)
I would think hotter oil would flow through the filter better.
I don’t typically go with the old way thinking of filtering first in case you had a failure the trash doesn’t get into the cooler. If you have a failure no matter where the filter is the cooler and lines should be replaced. |
GLENAMY and Unlimited jd, I really appreciate your input because I now see what everyone is doing. I don't have it plumbed yet so I can and will make this change. I can see where the filter is an obstruction to flow and the warmer oil would be able to pass through the filter easier? The larger internal passages of the aftermarket Hardin filter block is an obvious and probably needed upgrade. I did buy -10 fittings for the stock filter block but never looked inside to see if there was an internal restriction. I also feel better about the advice I received earlier about using the filter block as the sensor location. It's all in the way you plumb. You can understand my confusion about that location based on the posted drawing from the company showing a different plumbing design. I probably wasn't clear on what I planned on doing. The picture is worth a 1,000 words.
Thanks again to everyone's input. |
I now have new questions. I am convinced that the filter first is better than cooler first. With that said, I have attached a few pics of my engine right after I removed it. Looking at the oil cooler plumbing From Mercury can you tell if it went to the cooler or filter first? I can't find my old block adapters and don't know which is "in or out".
I sent an email to a couple places and they said the plumbing drawing I posted here is "just like Mercury does it" Also, do you guys think running the oil through the cooler against the direction of water flow is better than with with the water flow or no difference? Thanks for your help. https://cimg9.ibsrv.net/gimg/www.off...eefb4d9607.jpg https://cimg1.ibsrv.net/gimg/www.off...6aa2ccc3a5.jpg https://cimg4.ibsrv.net/gimg/www.off...b6438ed267.jpg |
The port on the outside of the adaptor would be "in to filter" and the one in the center would be "out from filter to engine (or cooler)"
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Originally Posted by GLENAMY 242SS
(Post 4858029)
The port on the outside of the adaptor would be "in to filter" and the one in the center would be "out from filter to engine (or cooler)"
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Looks like Mercury goes "with the flow of water"
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Against the flow of water.
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The place I bought the cooler from did say against the flow however I think in my pic the oil and water flow in the same direction? Thanks guys
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Yup, they say a little extra oil cooling with oil flow opposite of water flow.
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What size oil lines are you using?
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Everything is -10
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AN -10 should be more than adequate for what you're doing. 5/8 diameter - good fittings should keep that pretty consistent throughout.
Make sure your fittings are tight AND do not have tension in the hose routing that could make them back-off. They do not need to be "gorilla" tight (you'll gall the threads and the sealing surfaces) but tight enough that they will not back off. And if using push-lock hose, it's recommended to clamp them with a pinch-style clamp (not too tightly either - you do not want the hose's outer casing damaged). |
I see you went with non-thermostatically controlled coolers. Depending on their size and given you boat on cooler waters you may find the engines struggle to build oil temp. Buddy ran into that situation running Hardin coolers on 489's both on a nuclear powerplant cooling lake where the water in the summer is 90 + and at LOTO.
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Don't cheap out on the AN fittings use Fragola, Earls, Russel ect and don't mix them, match the hose to the fitting manufacturer. personally I think -10 is over kill for your engine
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I bought the misc. AN fittings through Hardin and CP. XRP line. These are the only AN fittings that I have so no mix and match other than the way some of them connect. Some are push on, some not.
Thanks for the heads up Tom about over tightening. I've been known to do that. For the oil lines they are the push on style and I did buy the special tool and the clamps for this type of hose. At the time, I didn't know -10 would be overkill. I think I selected -10 because the Hardin remote oil filter block at the engine was sized for -10. I'm assuming it's not a "bad thing" just overkill and overkill is fine with me. These coolers are pretty big (overkill) and supposed to work up to 700hp. They are the 3"x23" and they have the power steering loop in them too. I suppose I will find out this spring if they are too big. What is a "desired oil temp" while underway? https://cimg5.ibsrv.net/gimg/www.off...b685eee1c2.jpg |
I thought you were using compression not push lock, carry on
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I don’t think -10 for oil line is overkill at all. IMHO.
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Is anyone running one of these or similar? Or was everyone else smart enough to buy their coolers with the thermostat?
https://cimg6.ibsrv.net/gimg/www.off...0e0a3c5c65.jpg Not sure I'm going to have a problem but adding something like this is not a "bad idea" correct? Just momoney and plumbing..... |
whats the fitting size on the coolers are you having to use reducers to adapt the line to the cooler
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Cooler uses the same -10 fittings
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This particular thermostat Starts to open at 160 degrees fully open at 180 degrees
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Originally Posted by PQ290Enticer
(Post 4858097)
Cooler uses the same -10 fittings
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Originally Posted by PQ290Enticer
(Post 4858097)
Cooler uses the same -10 fittings
What we are concerned about with the fittings is the NPT (pipe thread) size. The NTP sizing is a strange outside diameter spec.and can easily lead to choke points in the oil flow. Internal thread size of the cooler and filter head should be a minimum of 3/4. As far as the thermostat just bite the bullet and do it right either the Hardin filter head with thermostat integrated or even cleaner discard (resale) the block adapter you have and buy the Hardin Block Adapter with integrated thermostat. Doing it right seems expensive but wait till you get it wrong because of cutting corners. Also buy quality AN fittings and whenever possible use long radius fittings if angles are required. |
Glenamy, My mistake. I wasn't thinking that the -10 might adapt to a smaller than 3/4" NPT side. Mine are all 3/4". My first real experience using AN fittings.
You don't dislike the idea of a separate thermostat correct? You're saying for a cleaner look replace the Hardin block adapter I have. I see the Hardin thermostat is set at 212 degrees. The "Earls Thermostat" is lower. I assume that the higher temp is more in line with marine use? Thanks again for the help. |
I know for a fact that Hardin uses the stock Mercruser thermostat. If you go with the block mount you still need the filter head. If you go with filter head you can use your existing Hardin block adapter You want to organize your lines to keep the total oil line length as short as possible. If you are using a stock filter head as your earlier post suggests that is 5/8 and restricts to about 3/8 internal oil passage.
Another question, did your machinist disable/plug your block oil bypass valve? |
Actually my stock filter head is 3/4" NPT. I don't see any "choking down" internally either. I am bringing them to my guy for "deburring". I can ask him then if he disabled, plugged the block bypass valve. Would that be a good thing or bad thing to disable? Mercury on their higher performance stuff come standard with an oil thermostat and it's a 212 degree unit? With oil temp being so important, why don't they have a lower setting on the thermostat.
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I have a pair of oem Merc HP 500 thermostatic filter heads that I might be able to let go of if that’s what you need. Includes the brackets that bolt to the back of the left bank cylinder head.
I used Hardin oil coolers with built-in thermostats so these are just sitting on the shelf. |
So this is the cooler I purchased as a kit. Whatever the "real" oil connections are, doesn't matter. ALL of my connectors are the same size. Stock remote oil filter block, cooler, and the Hardin block mounted adapter.
https://cimg2.ibsrv.net/gimg/www.off...2c94c458f5.jpg https://cimg3.ibsrv.net/gimg/www.off...ec410cdd59.jpg https://cimg4.ibsrv.net/gimg/www.off...0f74af1955.jpg |
Look inside of your filter head where the filter would cover. Look at the size of the oil passages your filter sees. That is the restriction in size I am talking about.
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Originally Posted by TomZ
(Post 4858116)
I have a pair of oem Merc HP 500 thermostatic filter heads that I might be able to let go of if that’s what you need. Includes the brackets that bolt to the back of the left bank cylinder head.
I used Hardin oil coolers with built-in thermostats so these are just sitting on the shelf. |
Originally Posted by PQ290Enticer
(Post 4855151)
My entire history of boating has been stock setups. This is the first year that I will be running modified engines. BBC's 500 hp. I did buy new oil coolers that are supposed to be good up to 700hp. They are not thermostatically controlled. I kept the stock oil pans. My builder said that at my hp level they would be fine. I plan on using the 160 degree thermostat for water. I am running the standard belt driven sea pump and brand new BBC standard (marine) circulating pumps. Should I also now start monitoring the oil temps? I see a lot of posts on here that refer to oil temps and how they modify their boating based on those numbers.
My next question is about 02 sensors. I was thinking about running fuel injection so when I ordered my new risers I had them weld in the 02 bungs. I have decided to go with carbs and was going to just plug them up. I was looking through the misc. new posts and pics and noticed that someone running carburetor's also had 02 sensors installed. Do some of you guys also run gages at the dash for AFR? FYI, my new engines have been dyno'd and set up so not sure it’s necessary to monitor? Looking forward to your comments. https://cimg8.ibsrv.net/gimg/www.off...f88bc1dfa.jpeg |
Nice. I should be able to mount my additional gages in the dash but that will be it. May have to redo the dash next year.
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I am not trying to beat this dead horse but I am confused yet again. I have attached a pic of an oil thermostat housing (offered by a company who should know?) and it shows the direction of plumbing is again contrary to advice given here on this site. I do agree with the advice given on this site that hotter oil is best sent to the filter first then to the cooler however I don't think this "thermostat housing" will operate properly if I don't follow their install instructions. I still have the "in-line" connection point for the oil temp sending unit so I could still get an accurate reading but with this thermostat I would be sending cooled oil to the filter. Maybe I should run as is and see if I actually need an oil thermostat? Post #70 shows what I currently have as a cooler and block adapter. My engines are 500hp. Thanks for your comments and advice.
https://cimg2.ibsrv.net/gimg/www.off...8073c07909.jpg |
Originally Posted by PQ290Enticer
(Post 4855151)
My entire history of boating has been stock setups. This is the first year that I will be running modified engines. BBC's 500 hp. I did buy new oil coolers that are supposed to be good up to 700hp. They are not thermostatically controlled. I kept the stock oil pans. My builder said that at my hp level they would be fine. I plan on using the 160 degree thermostat for water. I am running the standard belt driven sea pump and brand new BBC standard (marine) circulating pumps. Should I also now start monitoring the oil temps? I see a lot of posts on here that refer to oil temps and how they modify their boating based on those numbers.
My next question is about 02 sensors. I was thinking about running fuel injection so when I ordered my new risers I had them weld in the 02 bungs. I have decided to go with carbs and was going to just plug them up. I was looking through the misc. new posts and pics and noticed that someone running carburetor's also had 02 sensors installed. Do some of you guys also run gages at the dash for AFR? FYI, my new engines have been dyno'd and set up so not sure its necessary to monitor? Looking forward to your comments. |
Jeff, Did you read post #75? I am all for installing the thermostat my problem is the way they want it plumbed. Thanks for your comment.
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Still looking for input on post #75. Thanks for your help.
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I am using that same thermostat, it’s a nice piece. Makes for a neat install. Occasionally I boat in sub bath water temps and being able to get the temps up helps keep the oil from looking milky under the oil fill cap. The instructions are pretty clear. You will have in and out from the filter head and same from the oil cooler.
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Originally Posted by PQ290Enticer
(Post 4861036)
Still looking for input on post #75. Thanks for your help.
You're using a thermostatic unit for a reason - to not send oil to the cooler if it is already too cool. If you follow the Hardin/CP marine instructions, the thermostatic unit will only send oil to the cooler when it's hot enough to need cooling. However, there will be flow to the filter REGARDLESS of the oil temperature, which is what you want. You want filtration all the time, not just when the oil is hot. I would follow the instructions for the Hardin /CP instructions if this was my install. |
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