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xlint89 04-06-2023 06:08 PM

HP 500 oil cooler upgrade
 
2 Attachment(s)
So my HP 500 is being upgraded to around 550 HP and think I should be using a better oil cooler. This is all new to me, so please bear with me.

I'm hoping to minimize the amount of alterations required while upgrading the cooler, so I'd like to try and keep the new cooler as close to stock location as possible.


https://cimg4.ibsrv.net/gimg/www.off...26f6609977.jpg
This is how the stock cooler looks.

This is a pic from Hardin's site of the 3" cooler.

Attachment 577638

It looks to be much bigger in diameter and am concerned with it contacting the oil filter housing.

Has anyone done the upgrade and have any tips for me?

What brackets should I get for mounting? I assume the low mount like the pic above?

Attachment 577639

Also, for about $100 more, would it be worth getting the thermostatic oil cooler even though I have a thermostat in the filter housing?

Can the thermostatic oil cooler be painted? Or should it stay in the raw?

Thanks

smokediver 04-06-2023 08:00 PM

I think you will be fine with what you have. You could go to larger diameter oil lines for better flow


ICDEDPPL 04-06-2023 08:31 PM

I have one left , 16" long , 2" diameter and $200

https://cimg5.ibsrv.net/gimg/www.off...97af2707aa.jpg

tgorbett 04-06-2023 08:48 PM


Originally Posted by smokediver (Post 4864081)
I think you will be fine with what you have. You could go to larger diameter oil lines for better flow

+1

Run what you have and see if oil temps are an issue first, then address if necessary.

xlint89 04-07-2023 05:09 PM


Originally Posted by ICDEDPPL (Post 4864085)
I have one left , 16" long , 2" diameter and $200

https://cimg5.ibsrv.net/gimg/www.off...97af2707aa.jpg

Thanks for the offer, but not installing anything used. Read too many stories on here.

xlint89 04-07-2023 05:12 PM


Originally Posted by smokediver (Post 4864081)
I think you will be fine with what you have. You could go to larger diameter oil lines for better flow

Really? Thank you


Originally Posted by tgorbett (Post 4864088)
+1

Run what you have and see if oil temps are an issue first, then address if necessary.

Don't want to address it later. PITA to reach behind the engine when it's in the boat. Much rather address it while it's out. Thank you

ICDEDPPL 04-07-2023 06:59 PM

Sorry for the offer, I pressure tested them and put the other set on my engines without any concern but okay.

PQ290Enticer 04-08-2023 09:49 AM


Originally Posted by xlint89 (Post 4864152)
Thanks for the offer, but not installing anything used. Read too many stories on here.

So by now you know that you insulted the wrong guy. I'm sure you HAVE read stories about guys being ripped off on this and other sites but if you look back they did not have his name attached. Even if it wasn't your intention, you just included him with those POS. Tough break for you because he is also friends with everyone on this site that you would want to hear from about your question(s). Maybe you could reach out privately and apologize?
I think the HP 500 is 470hp so you are adding approx. 70 hp. My thought is that Mercury especially with their "Blue Motors" have a decent overkill built into that cooler. I assume you have a oil temp gauge so did you ever have the oil get too hot or did it keep creeping up or did it level off during a WOT run? Also, if you already have a thermostat then you don't need a second one. The ones that come with the tube style coolers are the ones that bolt to the block at the oil filter location. Its not part of the cooler. I think Hardin and CP sell the same items but I did look on CP's site and they sell "Plate Coolers" that may meet your needs. Good luck with your project.

xlint89 04-08-2023 10:27 AM


Originally Posted by ICDEDPPL (Post 4864163)
Sorry for the offer, I pressure tested them and put the other set on my engines without any concern but okay.

It's a new engine and I'm not installing a used oil cooler period, even the one I have. It's not the place to try and save a few bucks IMO. The one in my pic is 2"x17" already, so there would be no gain over stock.

There was no ill will in my reply towards you. If it came off that way, I apologize.

xlint89 04-08-2023 11:13 AM


Originally Posted by PQ290Enticer (Post 4864197)
So by now you know that you insulted the wrong guy. I'm sure you HAVE read stories about guys being ripped off on this and other sites but if you look back they did not have his name attached. Even if it wasn't your intention, you just included him with those POS. Tough break for you because he is also friends with everyone on this site that you would want to hear from about your question(s). Maybe you could reach out privately and apologize?
I think the HP 500 is 470hp so you are adding approx. 70 hp. My thought is that Mercury especially with their "Blue Motors" have a decent overkill built into that cooler. I assume you have a oil temp gauge so did you ever have the oil get too hot or did it keep creeping up or did it level off during a WOT run? Also, if you already have a thermostat then you don't need a second one. The ones that come with the tube style coolers are the ones that bolt to the block at the oil filter location. Its not part of the cooler. I think Hardin and CP sell the same items but I did look on CP's site and they sell "Plate Coolers" that may meet your needs. Good luck with your project.

There was no negativity meant towards him. If it came off that way, it was not my intent. I offered an apology in my reply to him, hopefully he accepts it.

What I meant was there are many stories of people trying to save a few dollars and getting burnt in the long run because of it. Oil coolers to me seem to jump out the most. Corrosion, metal particles, water impeller pieces, etc... I will be installing a brand new oil cooler is all. I wasn't even hinting at him selling bad parts.

Now with that said. I am new to all this oil cooler stuff and really do appreciate everyone's input. I have been basing my questions from everything I have read on here and from the performance parts sites.

They (CP, Diamond, and Mr Cool) seem to rate the 2" coolers up to 425 HP. Which is weird because Merc installed it on the HP500 engines. The sites list the 3" as being rated for 450 to 700. We're guessing my HP to be in the 550 range. That's why I assumed I would need the 3" as I'm almost in the middle of those ratings.

I understand what you're saying about watching the temps and addressing it at that time. However, the engine is out and will be much easier to install and modify the system now. And I plan on installing a new cooler regardless. Don't want to buy a 2" now, and need the 3" after I make a top speed pass later.

Most of the replies thus far seem to suggest the 2" cooler is sufficient enough for my application. I am listening.

Not trying to ruffle any feathers, trying to learn from people that have been there before.

I really do appreciate the replies. Keep them coming please.

I want to get these parts ordered up and on their way so i can install them once/if my engine ever gets done. :picard1:


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