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gastite

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"Why would my riser elbow have

"Why would my riser elbow have a faded white spot
where the elbow bends down to the 3’’ outlet. It’s the
bend just before the rubber meets the 3’’outlet.

There is a white spot, like a torch was sitting in that one spot.

I just changed my stats. I was told to do it. I am glad I did. Both
had 140 degree stats. I could never understand why I was not moving
the temp gauge, I thought I had no stats. I installed new 160 degree as requested by Crusader. The engine that has the new white spot was the engine I found the 140 degree stat but it was broken. I am thinking that now since I have the proper stat and the engine gets up to temperature the metal is getting adjust to the new higher temp.

what do you guys think?

After changing the stats I ran the boat for about 2 hours at 7 knots and 30 minutes up to speed, 3200 rpm’s. The ship canal is one hour to Lake Washington from where I am and one hour back at 7 knots. I have no idea what could cause this."
 
"I think that if you are raw w

"I think that if you are raw water cooled, you just took out the right thermostats and put in the wrong ones. If your gauge didn't move with 140 thermostats in the engine you have a problem with the gauge. If you are freshwater cooled, you need the 160s and you're OIK now.

The risers are not effected by the thermostats, the water passing through them is constant and not controlled by the thermostat. Your hot spot has to be just that, a hot spot. I would check the area with a laser pyrometer and if you haven't had the risers off recently, I'd pull them and clean them out."
 
"Thanks Rick: I have new gauge

"Thanks Rick: I have new gauges and I am fresh water cooled.
I have never taken off the risers due to not seeing any problems. I was going to try the 1 gal of muriatic acid with two gallons of water and see if that helps.
Its funny because now both engines are running
at 120 degrees and I was so happy.
Its a boat!!
"
 
"risers are throwaways at 4 ye

"risers are throwaways at 4 years, if they see generally salt water operation. And, that's even if you flush the raw water system out after each use. Large flakes of expanding cast iron rust are not fixed by an acid bath.
Engines are too cold at 120 degrees, causing more cylinder wall wear than necessary. You should be able to touch the thermostat housing at cruise power for only about 1/2 second without burning yourself. You may want to invest in a $50 IR thermometer.
Burned paint indicate hot spots due to poor raw water flow which in turn, can be caused by clogging in the risers."
 
"NEED HELP! HAVE 1988 454 FWC.

"NEED HELP! HAVE 1988 454 FWC. I TRY TO START ENGINES EVERY 1 OR 2 WEEKS. LAST TIME STARBORD HARD TO START, RUNS ROUGH AND WILL NO IDLE. WENT THRU INGITION ALL OK. PULLED EXHUAST ELL AND HAVE WATER IN MANIFOLD. DOES NOT SMELL LIKE ANTIFREEZE. COULD THE MANIFOLD BE OK WITH THE WATER COMMING FROM THE ELL? OR SHOULD I REPLACE BOTH?"
 
"Don,

Please start a new th

"Don,

Please start a new thread for your problem, but yes, providing the mating surface is good."
 
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