SoCal Jet Boats

Tech Talk => Engine Mechanical / Electrical => Topic started by: jaycetti on July 30, 2021, 03:38:36 PM

Title: LS Cooling Setup
Post by: jaycetti on July 30, 2021, 03:38:36 PM
Just picked up my first float!  77 Hallett Mini Cruiser.  I've built many customer cars and trucks but never a boat.  I'm going for nice reliable family cruiser, not a rocket on the water, so I'm dropping in a mild built carbureted LQ9 6.0L.  My questions are concerning the cooling setup....

I've been trolling around and it looks like many of the guys going LS are using the LSX Adapters and skipping any type of thermostat. 

(https://i.ibb.co/gMzPFDQ/LSX-Adapters.jpg)

Then if you go on Hardin Marine you come across this expensive coolant crossover thermostat. 

(https://i.ibb.co/MVcy75L/Hardin-Crossover.jpg)

I'm going wet exhaust through transom, so I'm just unsure which is the best option and why one works better over the other.  My past experience with cars tells me the thermostat setup will help the engine come up to temperature faster and cause less stress on the engine.  If that's the only real benefit of going thermostat then I'm unsure if it's really necessary.  Any advise would be greatly appreciated.  I'm also going to have many future questions regarding other systems, so I'm sure you'll be seeing more topics from me in the future.  And, I can't wait to get the boat out there and meet up with you guys!  Looks like a great group.  Pics below of my new purchase....
(https://i.ibb.co/stpKgQz/1.jpg)
(https://i.ibb.co/HVnHy8T/2.jpg)
Title: Re: LS Cooling Setup
Post by: TrollerDave on July 30, 2021, 04:00:50 PM
Welcome to SCJB. Those are good boats. Here is a thread about plumbing just for reference.

http://www.socaljetboats.com/engine-mechanical-electrical/plumbing-help-needed-for-ls-motor-install/msg345564/#msg345564
The topic of tstats has been discussed a lot with older style engines. Usually, boat motors are built with extra clearances because of running at higher rpms and the difference in running temps because of open cooling (no tstat).


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Title: Re: LS Cooling Setup
Post by: jaycetti on July 30, 2021, 04:14:39 PM
I appreciate the response.  I've actually read that post.  Again, it references using something like the LSX Adapters and not running any kind of thermostat setup.  I'm more or less hoping that I'll get some info from someone that has ran the Hardin Marine thermostat setup and thinks it's worth it's cost.
Title: Re: LS Cooling Setup
Post by: Hood325 on October 24, 2021, 08:56:00 PM
How did you end up running your plumbing? What was the adapter part called you listed? Pics if you have them. I am getting ready for it and this was the most helpful post I've seen yet thanks
Title: Re: LS Cooling Setup
Post by: Hardcore1 on October 28, 2021, 07:06:33 AM
I have a pair of polished water cooled exhaust manifolds for sale for a LS if any one is interested, ill list them in engine parts for sale later today! asking $500
Title: Re: LS Cooling Setup
Post by: 76stpsquirtboat on October 28, 2021, 07:18:45 PM
I appreciate the response.  I've actually read that post.  Again, it references using something like the LSX Adapters and not running any kind of thermostat setup.  I'm more or less hoping that I'll get some info from someone that has ran the Hardin Marine thermostat setup and thinks it's worth it's cost.
Definitely worth it, you can regulate the temp somewhat with restricting the flow into the engine but the thermostat is nice cause it keeps it at a good operating temp all the time. I had issues with condensation and moisture in my heads because the engine wouldn’t get past 120 degrees. After installing the thermostat she runs at 175-180 all the time and no more moisture. I’m running a 6.0 LS bone stock long block, just a Holley intake and carburetor


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