HP500 EFI Closed Cooling and HP525 EFI Serial #
 

Hi All,

I haven't been able to find a closed cooling upgrade kit for the HP500 EFI from Mercruiser. One idea I had was that the HP525 EFI and HP500EFI are both very similar in exterior looks. I'm guessing that it might be possible to buy a set of parts that fit the HP525 and use them to install closed cooling system on the HP500.

Would someone with HP525 EFI engines be willing to send me a serial # from one of their engines? I can use the # to order a service manual and parts list for the HP525 and start researching whether this might be possible.

If you know of a closed cooling upgrade kit part # for the HP500 EFI, that would be even better.

Thanks,
Garrett

Re: HP500 EFI Closed Cooling and HP525 EFI Serial #
 

Prob be a LOT cheaper to go Aftermarket ....

Re: HP500 EFI Closed Cooling and HP525 EFI Serial #
 

There are aftermarket kits for this that have been talked about on OSO. I wold post this in the General Discusion area.

Jon

Re: HP500 EFI Closed Cooling and HP525 EFI Serial #
 

Garrett .. i was looking at some just the other nite that were nice ... I'll try to remember and post the site .m

Re: HP500 EFI Closed Cooling and HP525 EFI Serial #
 

Thanks! Any pointers will be greatly appreciated. I can't find anything on the internet.
Garrett

Re: HP500 EFI Closed Cooling and HP525 EFI Serial #
 

Innovation Marine in Sarasota FL, does a great job with closed cooling on their setups. They have rebuilt some 500efis that I have seen with closed cooling, and it looks amazing. I'll email you their number tomorrow.

Corey

Re: HP500 EFI Closed Cooling and HP525 EFI Serial #
 

Thanks Corey for the pointer. I gave them a call today. They don't have a kit for the HP500 at the moment. I talked to Scott. He did say that they have gotten several calls concerning a kit for this motor and they have someone looking at what could be done. Anything they could sell me right now would require me to do a significant amount of work to get it all plumbed in as it wouldn't be a "bolt on" type of kit.

I left them my number. They said they would give me a call back and let me know what they come up with. I'll keep you all posted.

Garrett

Re: HP500 EFI Closed Cooling and HP525 EFI Serial #
 

FYI

The HP500 and HP500efi use cast iron heads, while the HP525 uses a aluminum head with water ports on the faces of the heads where the heat exchanger is plumbed too. Now I'm going off memory(of 525's i've seen), but I'm 99% sure this is how there setup. So a HP525 setup wouldn't work anyways.
LE