Jump to content
ndahlberg12

Climbing temp help

Recommended Posts

ndahlberg12

Took my 2003 Malibu Sportster out for the first time tonight with my carbed indmar 310. Yesterday I installed a new impeller and test ran with the fake a lake. All was good.

Tonight I unloaded and idled out through our no wake zone and noticed the temp climbed to 160 pretty quick and stuck there. Once I got clear of the no wake zone I checked everything for leaks all was good and slowly increased the throttle to full and drove across the lake, by the time I got across the lake temp was over 200 and climbing. Slowly let out of the throttle and started getting temps flashing on the dash topping out at 218. Flipped open the motor box and checked everything over and all looked fine. Left the motor box open and drove back to shore where by this time I was back down to 160. Picked up the family and tooled around the lake keeping it under 2500-3000 rpms and it stayed around 160. But as soon and I would pour the throttle on I would start to get temps increasing again.

Any thoughts? I've rechecked the impeller and all looks good. Hoses are free of kinks. Pickup is free of obstructions on the hull.

Sent from my iPhone using Tapatalk

Share this post


Link to post
Share on other sites
Bozboat

Did you reuse the old gasket?

Share this post


Link to post
Share on other sites
ndahlberg12

No sir. New gasket with impeller.

Sent from my iPhone using Tapatalk

Share this post


Link to post
Share on other sites
Mackie 12

Trans cooler plugged?

Share this post


Link to post
Share on other sites
Bozboat

Good, I figured out not to reuse the old gasket. I was thinking the pump might be sucking air at higher speeds. Or the transmission cooler maybe partially clogged

Share this post


Link to post
Share on other sites
dihrdskir

My guess is it's an obstruction of some sort given that the temp climbs under load and returns to normal under idle conditions. The engine is not getting the volume of water it needs in times of high demand. In my experiences I have seen a number of causes. Debris ahead of the trans cooler, a blocked raw water strainer and a sticking thermostat (yes the first run of the season) are all scenarios I have seen and each had symptoms of the condition that you describe. Check all three.

Share this post


Link to post
Share on other sites
Malibudude

The cold water in take for the trans maybe the culprit. Looking at the engine it'll be on the right side (of a DD engine) a roughly 5" black metal cylinder. Remove the hoses and check the metal screen for debris.

Share this post


Link to post
Share on other sites
tvano

worthwhile to get into the habit of spinning the rpm's up to the 1500 mark for a two count when first launching to generate enough suction to pull lake water into the pump.

once it's primed you should be good to go.

Share this post


Link to post
Share on other sites
edwin

Bet ya a cold beer here's your answer...

Trans cooler plugged?

The cold water in take for the trans maybe the culprit. Looking at the engine it'll be on the right side (of a DD engine) a roughly 5" black metal cylinder. Remove the hoses and check the metal screen for debris.

Share this post


Link to post
Share on other sites
racer808

Could be your gauge too. Start at the back with the above suggestions & work your way forward

Share this post


Link to post
Share on other sites
airking26

I had a similair issue and it turned out my thermostat was corroded. Less than $10 at Napa for a new one. It's a little work to get out but wouldn't hurt to check.

Share this post


Link to post
Share on other sites
Andrew63

Thermostat was my problem and it was only 2 years old from new...

All the above water intake suggestions are the cheapest checks to do 1st, trans cooler & raw water filter if you have one.

Share this post


Link to post
Share on other sites
ucontrol

I do not know if this will help, But when I changed the impellar, my problem started. It was brand new and appeared to be ok. But the temp increased and the boat went into limp mode. As soon as I idled back down, the temp went back down. I put the used impellar back in and everything was ok. The impellar that was new was the globe run dry. The Johnson impellar seems to work fine. The globe did not appear to be bad at all. But it certainly did not work.

Share this post


Link to post
Share on other sites
ndahlberg12

I do not know if this will help, But when I changed the impellar, my problem started. It was brand new and appeared to be ok. But the temp increased and the boat went into limp mode. As soon as I idled back down, the temp went back down. I put the used impellar back in and everything was ok. The impellar that was new was the globe run dry. The Johnson impellar seems to work fine. The globe did not appear to be bad at all. But it certainly did not work.

I installed a new Johnson on Monday, have you continued to use Johnson's?

I will inspect this along with the pick up grate and the oil cooler once I get off work. Thanks for all the help guys.

Share this post


Link to post
Share on other sites
racer808

how often do you guys change thermostats? not a yearly thing is it?

Share this post


Link to post
Share on other sites
Bozboat

I installed a new Johnson on Monday, have you continued to use Johnson's?

I will inspect this along with the pick up grate and the oil cooler once I get off work. Thanks for all the help guys.

I have had better luck with the Johnson. The globe I had worked for awhile and then got tired of working. Still looked pretty good.

how often do you guys change thermostats? not a yearly thing is it?

If you are using a marine thermostat, it should last for years

Share this post


Link to post
Share on other sites
Mackie 12

On the fake a lake pull the raw water pump cover off to see if your are getting flow. If you are keep working foreward until you find the block. I would also pick up a T/Stat just to rule it out. Outside of this I am stumped.

Share this post


Link to post
Share on other sites
dihrdskir

how often do you guys change thermostats? not a yearly thing is it?

Rarely and even then only if it is completely shot. In a marine application sitting idle is what kills them. We don't winterize down here so I run mine on the hose once a month. I get it up to temp, shut it down and put it away. Little things like this go a long way when it comes to starting off a new season hassle free.

Share this post


Link to post
Share on other sites
ndahlberg12

Took off the Intake hose and back flushed the water pick up grate. Ran it on the driveway for 20 mins and couldn't get it over 160. Starting to think whatever was in there may of been a fluke and blew out already. Only thing I can think of is grabbing a thermostat and taking it back out to the lake and see what happens. Thought about taking a thermostat just incase. Maybe wishful thinking but I hope it just broke open.

Sent from my iPhone using Tapatalk

Share this post


Link to post
Share on other sites
Mackie 12

Pull the T/Stat and put it in a pot of water on the stove and boil. This will tell you if it is working or not.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×