2005 xr6 150 1B029436 high temp alarm issue

[Dave Ervin]

Sat. 5/18, No idle alarm or low speed alarm, when I get her up on plane a single constant alarm goes off. I shut it down, wait a minute restart no alarm. I can idle to low speed no heat alarm. No temp gauge. I checked thermostats, tested put back in. These are original , 19 years old I am going to replace. Waterpump psi at idle is 2. Low speed 3 psi, up on plane 6 psi but only for a few seconds. I did a motor flush last fall, no change. Checked poppet valve, took apart cleaned, checked diaphragm, gaskets etc put back in last week, 5/10. Any help suggestions?
thx
Dave

[JOE54]

always start at source remove /replace w/p and all 3 gaskets

[Dave Ervin]

Thanks Joe. I am replacing poppet valve and thermostats this weekend. See what happens, waterpump will be next. Dreading this. Last time the bearing race bottom of block came out and had to push it back in. What a nightmare ! Any suggestions on this ordeal?
thx Dave

[JOE54]

im hoping its a popett problem for ya DAVE i know those seals are a pain to get back in mabe its still stuck in crank

[EuropeanAM]

Thanks Joe. I am replacing poppet valve and thermostats this weekend. See what happens, waterpump will be next. Dreading this. Last time the bearing race bottom of block came out and had to push it back in. What a nightmare ! Any suggestions on this ordeal?
thx Dave

I am going to restate Joe's advice: ALWAYS, ALWAYS start AT THE SOURCE: The Water Pump. If, and ONLY if you still have problems after complete pump replacement should you be looking to replace thermostats, poppet valve, hoses, gaskets, or other obscure components.

^^^^ This method has been proven more times than I can count during my 47 years working on these engines.

[Dave Ervin]

Thanks for good advice, experience will prevail!!

[JOE54]

every time DAVE

[Dave Ervin]

Got new water pump in, same issue as before, bearing race dropped out. Still has same tool from before, got it back in. Pump had cracked impeller, 3 broken gaskets. Test run went about a 1/4 mile about 3/4 throttle no alarm. Put down to full throttle and alarm goes off. Shut down immediately. Let it rest for a minute started right up ran at 3/4 throttle for about a mile no alarm. Opened back up for about 100 yards, alarm goes off. I think it is poppet valve. Carrier may not be seated correctly. Any suggestions?
thx Dave

[Dave Ervin]

After replacing waterpump, psi was 5 at idle and 15-20 at higher rpm’s.

[Dave Ervin]

What can cause tach jumping around and maxing out with engine running half throttle?
It does this a lot. What can I check for?
thx Dave

[EuropeanAM]

Have you REPLACED the carrier? What was the water pressure at WOT?

In most cases, the carrier doesn't require replacement (just the grommet that sets INTO it with lips on BOTH sides of the carrier).

[Dave Ervin]

Yes, didn’t know you didn’t have to replace. It is a bear to get in

[Dave Ervin]

I believe around 15