Hey Guys,

After identifying a faulty sea pump impeller as the cause of a minor over heating (185 degrees), I started pulling both sea water pumps to replace their impellers. PO said he did it last year, but it appears he meant the circulating pumps as they look fairly new. I noticed some rust around the 4 exhaust manifold/riser hoses on the thermostat housing so I pulled the hoses to check and clean. What I found was 2 very poor condition housings. Hose ports plugged almost solid with corrosion, frozen check ball/spring assembly, frozen thermostats etc. In my opinion they are beyond cleaning and need to be replaced.

So, at this point I need to make a decision. I need to replace the thermo housings. My question is do I go with the newer version 6 hose setup (currently have a 6 hose setup), do I go with the more modern and cleaner 4 hose setup (changing the riser gaskets to the respective correct 4 slot one) or do I replace the thermo housing and recirculating pumps with a crossover kit? Prices aren't too far off from each other, so I wanted to get some input on everyone's thoughts. Through a lot of searching on here it appears the sea water pump has enough capability to circulate cooling water through the motor with out the circulating pumps. I also sense that if I were to go with cross overs, to ensure I get ones with the bypass option. Regardless of what setup I will be installing new thermostats and replacing the hoses as they are looking pretty rough inside as well.

Background on the boat: Baja 280 sport with twin 454 Mags and B1s. stock motors with stock exhaust manifolds/risers.

Thanks in advance for your comments and as always thanks for a great site with a lot of great info!

Keep circulating pump and get the 4 hose t-stat housing set up and don't look back.

I am pushing 700hp and have a crossover and it works great, with the right Stewart Racing vented thermostat. The boat pretty much stays right at temp, unless I drop to idle after a long hard run. It will climb to 190 and then drop to 150 after a minute or 2. I have been in 34 degree water and the boat wouldn't get over 135 though. Don't think a circulating pump would help that.

Mee too, and it does. That's why in my area I use circulating pump set-ups almost exclusively, but rare occasions you can't.

Thanks guys, I ordered a pair of stainless four hose housings and new thermostats. Should be in tomorrow or Friday and hoping to get it out and test it this weekend. While I was waiting it out I rebuilt the sea water pumps and flushed everything out. Should take care of my issue and get me back out enjoying the boat!

Thanks again guys!

x2