Not a good sign!!

[no_rulz25]

As most of you know from previous posts that I’ve been overheating recently and everyone agreed that most likely it is the impeller. I replaced the impeller today and this is the old impeller I took out.

0570B8DF-78B3-4BC7-935B-CA2EE2C712E7.jpeg

A9D66FAC-8BA3-4343-A62F-AAD73AA01ACE.jpeg

So, it looks like the impeller was not the issue!! So thinking the water pump may be bad. Thoughts?

[arcticzale]

New to the forum, not to boating or mechanics- just ran through this issue myself. Is it just a high speed overheat?
My issue was actually the paint on the drive diverting watwr away from the water intake of the outdrive. Repainted the drive and that solved my issue. I got new sensors for the manifold risers, checked the exhaust riser ports and replaced the riser gaskets, but didn't install the sensors. Painted the drive unit before I installed the sensors and it has been perfect. Another issue can be the thermostat or the hose from the drive to the transom could be cracked. Sorry if this is redundant and you've posted elsewhere about this, just trying to help.

How does your drive paint look? I have the 8.1GXi and my drive was in need of some love. Here's a before picture :

19023353_10213438226095277_9119214607152592886_o.jpg

And after:

20180603_134519.jpg

[cmattj]

Well well. It’s looks good with just some wear marks.

This is is closed cooling ( anti freeze bottle)? Without a code reader it will be difficult to determine if it’s fresh water flow ect exhaust or engine temp.

You can diag visually with a ir temp gun on manifold and engine but your running drive down and on muffs for water.

Put a new “ Volvo” impeller in it and let’s get a temp gun for running it.

It idle overheated and high speed overheating so it’s a flow issue or if closed system engine pump flow.

Are the exhaust manifolds original and do you flush it every outing with freshwater?

You need to determine water flow out the back on muffs before we look for engine pump or manifold restrictions

[AsLan7]

New to the forum, not to boating or mechanics- just ran through this issue myself. Is it just a high speed overheat?
My issue was actually the paint on the drive diverting watwr away from the water intake of the outdrive. Repainted the drive and that solved my issue. I got new sensors for the manifold risers, checked the exhaust riser ports and replaced the riser gaskets, but didn't install the sensors. Painted the drive unit before I installed the sensors and it has been perfect. Another issue can be the thermostat or the hose from the drive to the transom could be cracked. Sorry if this is redundant and you've posted elsewhere about this, just trying to help.

.


How does your drive paint look? I have the 8.1GXi and my drive was in need of some love. Here's a before picture :

19023353_10213438226095277_9119214607152592886_o.jpg

And after:
20180603_134519.jpg

.
Hey arcticzale. So glad you found us!

Thx for the pics too.

I’ll have to admit, I have never heard of drive paint causing an overheating issue by diverting water from the intakes. Amazing that you figured that out.

Feel free to start a new thread with an intro only if you have time. We love hearing how folks get into their Cobalt’s. And as you know we love pics.

Again, welcome aboard mate!

.

[AsLan7]

As most of you know from previous posts that I’ve been overheating recently and everyone agreed that most likely it is the impeller. I replaced the impeller today and this is the old impeller I took out.

0570B8DF-78B3-4BC7-935B-CA2EE2C712E7.jpeg
A9D66FAC-8BA3-4343-A62F-AAD73AA01ACE.jpeg

So, it looks like the impeller was not the issue!! So thinking the water pump may be bad. Thoughts?

.
Hopefully you don’t go down the same overheating path I went down last year NR_25....


viewtopic.php?f=47&t=527&hilit=Overheating



.

[Big Block Power]

As most of you know from previous posts that I’ve been overheating recently and everyone agreed that most likely it is the impeller. I replaced the impeller today and this is the old impeller I took out.

0570B8DF-78B3-4BC7-935B-CA2EE2C712E7.jpeg
A9D66FAC-8BA3-4343-A62F-AAD73AA01ACE.jpeg

So, it looks like the impeller was not the issue!! So thinking the water pump may be bad. Thoughts?

.
Hopefully you don’t go down the same overheating path I went down last year NR_25....


viewtopic.php?f=47&t=527&hilit=Overheating



.

I hope no one goes through what you did last year. I know I would not have. Your a trooper that's for sure.

[AsLan7]

As most of you know from previous posts that I’ve been overheating recently and everyone agreed that most likely it is the impeller. I replaced the impeller today and this is the old impeller I took out.

0570B8DF-78B3-4BC7-935B-CA2EE2C712E7.jpeg
A9D66FAC-8BA3-4343-A62F-AAD73AA01ACE.jpeg

So, it looks like the impeller was not the issue!! So thinking the water pump may be bad. Thoughts?

.
Hopefully you don’t go down the same overheating path I went down last year NR_25....


viewtopic.php?f=47&t=527&hilit=Overheating



.

I hope no one goes through what you did last year. I know I would not have. Your a trooper that's for sure.

You guys kept me goin BbP. Lots of encouragement and wisdom on this site Thank you again.

Now let’s get back to our regularly scheduled program on this thread to get NRz25 goin again.

.

.

[no_rulz25]

Well well. It’s looks good with just some wear marks.

This is is closed cooling ( anti freeze bottle)? Without a code reader it will be difficult to determine if it’s fresh water flow ect exhaust or engine temp.

You can diag visually with a ir temp gun on manifold and engine but your running drive down and on muffs for water.

Put a new “ Volvo” impeller in it and let’s get a temp gun for running it.

It idle overheated and high speed overheating so it’s a flow issue or if closed system engine pump flow.

Are the exhaust manifolds original and do you flush it every outing with freshwater?

You need to determine water flow out the back on muffs before we look for engine pump or manifold restrictions

This is a raw water cooling system, no coolant bottle.

The new impeller is an OEM Volvo part.

Manifolds are original and yes, I flush after every use with a hose hooked to the engine flushing port.

[Big Block Power]

It's 5 years old so it could be lots of things in sure. Small conectors between the drive and engine.
Hope you find it soon.

[no_rulz25]

Hope so too, thanks!

[smokymance]

Is it me or do the impeller fins look like they weren’t all pointing the right way. Maybe one of them was pointing the wrong way not making the propoltion in the housing not as efficient as it would have if all the fins were “trailing” the correct way. When I took my impleller off, all the fins were biased as trailing arms agains the rotation of the impeller. Just speaking out loud here.

[Big Block Power]

Is it me or do the impeller fins look like they weren’t all pointing the right way. Maybe one of them was pointing the wrong way not making the propoltion in the housing not as efficient as it would have if all the fins were “trailing” the correct way. When I took my impleller off, all the fins were biased as trailing arms agains the rotation of the impeller. Just speaking out loud here.

No that's not a big deal. They auto correct themselves unlike my typing. Lol
Mine was the same way.

[smokymance]

Oh ok, it was a theory that i had but im glad it got proved wrong as i always worry if they were heading the wrong way!...good to know!