thermostat

Well I think I found the culprit...the outlet neck of the tranny cooler was kinked/crushed on one side and was allowing air in. I was able to straighten it out for now. Hopefully I won't need a new one. Efficiency test of the RWP passed and tops of risers were much cooler than before. Temp was within normal operating range. All is good for now. Thank you to all your suggestions and help.

Pulley alignment is an improvement you can do for belt life, but has nothing to do with the overheating problem.

Good luck finding the air leak.

Don't discount that you could still have old impeller pcs in & around the t'stat, blocking flow.   Could be more than 1 thing going on . . .

What brand and model of pump?

If the pump has a groove for the o ring I don't think you use a gasket with it too. My Jabsco pump uses a paper gasket,my Dads PCM Sherwood pump uses just the o ring. If you have a Sherwood pump I would use Sherwood impellers too,none of that Sierra brand stuff.

it does sound like an air leak---air is getting in somewhere

Got around to running a few tests...

1. Checked the tranny cooler for blockage - there was nothing at all
2. Did RWP efficiency test. I isolated the RWP by taking off hose of the out side of the tranny cooler and put in a bucket (actually ice chest). Took the hose off the thermo housing from the RWP and put another hose on to extend it. At 3K RPMs I filled up 5 gallon bucket halfway in 15 sec. According to link given earlier in thread, it should have filled up the entire 5 gallon bucket in 15 sec. So I put a new impeller in. Did the same test. Got the same result.
3. Put everything back together - all the hoses back in the right spot. Then disconnected the hose from the out of the water pick up filter and put in the bucket. Tightened up all clamps. Started engine - went to 195 idling. Risers too hot to touch. Shut her down.

Any suggestions? I'm not sure what else to do. I know I need to get hold of a IR temp gun but the engine is obviously getting too hot. I have replaced the thermostat (143). Replaced the impeller. Checked for blockage in the tranny cooler. Checked for air leaks. And she's still running too hot.

I've been posting this a lot lately, but I feel like it's a good general list of things to check:
Skidim Overheat Troubleshoot

My favorite note, is checking the exhaust risers. Because, if you're getting water through the system, the risers should be warm but not hot, regardless of what the thermostat is doing.

How do you check inside the tranny cooler?

It is important to note that I installed a new 143 thermostat, which I tested before hand on the stove. It opened up as it should.
Don't know if this important or not but the water temp from the exhaust was 140.

8122pbrainard wrote: I concur with both Brain and Greg. Think about this, will the pressure from the hose gives you a false indication of cooling since the boat isn't woking under normal conditions on the water - correct?? I'm going to pull a "79" here but, do you have any friends that can help you? Did you ever clean up the mating surfaces as recommenced and HOW DID YOU DO IT?????

EDIT: Trey, your profile is very vague!!! Fill us in some more.

You're more likely to get a true to life reading my using the bucket method: http://www.correctcraftfan.com/forum/forum_posts.asp?TID=24767&title=how-to-run-your-boat-out-of-water-bucket-method
over using the fake a lake.

The fake a lake could push water into the system, which isn't bad necessarily, but you won't know if your impeller and everything is pulling well enough on its own.

Is there a procedure or recommendation for testing the temperature on trailer using a fake-a-lake? I replaced the thermo, took out some big flakes of rust in the housing, inspected the impeller (which shows no sign of wear), tightened down all clamps, have good seal on screened filter, tested the RWP to make sure it is pumping water...anything else?

teelta wrote: Man does that Permatex stuff ever dry?

No, and it needs to go on thin and even.

Man does that Permatex stuff ever dry? It has been on there for over 24 hrs and it is still tacky and smearable...is that a word?

At my buddys shop On marine, Jet Skis and Motorcycles we use ThreeBond 1211 gasket sealer as do most of the shops in the area. And for silicone gasket maker we use Toyota FIPG gasket maker available at toyota dealers
Its a lot better than permatex.