According to Randy Schleuss, the HP525 in his new 29 foot Kryptonite overheated within a few hundred feet of the finish line, which cost him #1 in Savannah. He could recover and finished #2.

This is one more in a series of reports that say that the closed cooling system of the HP525 is underdimensioned and is prone to overheating. Comments? Reports?

Overheating problem w/ the HP525 were reported in this thread:

http://www.offshoreonly.com/forums/s...&highlight=525

Not that your blaming Mercury for the # 2 position...But to overheat the thing???
You guys running temp gauges?
The trick is to see it(look at a gauge)getting hot and back off the sticks a little.
Then after the #1 Trophe and check, call Mercury and discuss a fix.

I bet the number 1 guy didn't have to back off the throttles. WHAT! BACK OFF THE THROTTLES?
Now that sucks!


Shame because I hear n see boaters are having problems with the 525's but No on wants to admit they have a problem.


The first step is to admit the problem!

APBA website says killswitch came out. Is that the real story?

It's total bunk and it always makes a team look stupid. Whenever someone has technical problems, the first thing that makes the rounds is "the dumb chit pulled the kill switch." But APBA should know better than to engage in gossip.

According to Randy, who was in the boat, the engine overheated and the computer did shut it down.

The APBA website also claims that Randy & Glenn "stole" the lead.

Was this the first time that they ever run the boat? I don't see how a closed cooling malfunction could just happen. Not trying to bust anyone's stones - just wondering.

Hmm, a suggestion of pilot error, perhaps?

Well, it was the second time they ran the boat (Kilo runs Friday, race Saturday) and it was the third time the boat has been on the water (testing on Wednesday.)

A closed cooling malfunction can happen easily if the heat exchanger is underdimensioned. Heat exchanger can't exchange enough heat, computer sees high water temp, computer switches into limp home mode. A more than likely scenario given the 100+ temps in Savannah plus the past reports of problems with the HP525 cooling. And summer has not really started.

I will be taking delivery of a Kryptonite with HP525 in a week (hopefully.) If the weather stays as hot as it is, I might be able to replicate Savannah conditions.

Calling all gearheads: Assuming there is a problem, how could it be rectified before Merc gets around to rectifying it - forgetting about APBA regs for the moment? What would be the solution? How hard would it be to solve? Auxiliary heat exchanger? Second water pump?

I've read somewhere that with other engines with closed cooling, Merc recommends a 2nd water pump when driven in water temps higher than 85 degrees. Can't find the source. Help?

I read the other thread about overheating but no one put any temp numbers down. What kind of temps are we talking about?