Van engine temp fluctuating

[Bryce C]

My engine temp in my van has been fluctuating a bit. 80% of the time it is normal, reading 210 on the gauge on my dashboard. However 20% of the time it fluctuates up to 220 to 225 then comes back down to 210. It isn't a matter of whether I am stopped/idling or cruising at highway speed. It does it in both situations seemingly equally.

Then today I just left the ball valve to my tm heat exchanger wide open while driving and the van engine maintained a consistent 210 the whole day without a single fluctuation. I'm often worried about the engine overheating when I run the tm for hours..

 

[hogjowl]

I think this is the day for medical advice. You’ll have to wait until after legal advice and tax day. Try Monday or call a mechanic.

 

[Bryce C]

I think this is the day for medical advice. You’ll have to wait until after legal advice and tax day. Try Monday or call a mechanic.

"How long will scoffers delight in their scoffing?"

 

[Nate The Great]

Amazon product
View: https://www.amazon.com/OEMTOOLS-87009-No-Spill-Coolant-Filling/dp/B01A2CQSU6/ref=sr_1_1_sspa?crid=2IRQ1DFOCVNR9&dib=eyJ2IjoiMSJ9.F5nNaC9xMOvmqIn_JRvIH1QfBxk3c9IEnKTvTNpsEE0ApIoMbGRcuo6KKOLMWamcpcZzvYjgY1qCcFa5wYncwBQYiGj2pR-RU8fQVkgPk5Wj-9FP0_4dFe8MSZt9SBpRoYrkLbVhU2a8mWHqoFZKFlUw7tF8lNOw8vOAGJAtQ4ytLb5zOFEMjlBD3Ro2XVnNAq7HZ4JgFqWqiIZu0H44CLJgx603pMGJ5PnYrk2S9ABUrL_o2Bu0SXCGVsGTrOd46Ix3AfUFMNHvqUvnNdpXp0IwdHRFlsGz9JS13FzElgY.AnqCpwteNebqfWx4uCyshgx2YNsKWqRU8ioA7fHMS2s&dib_tag=se&keywords=radiator%2Bfunnel&qid=1758937942&sprefix=radiator%2Bfunnel%2Caps%2C367&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1



I'd use this to burp the system.. You may have to rev your engine and also put the heater on while doing so.. Did you ever put a T or Y on the coolant outlet from the HX?

It takes a while to make sure it's burped.. I don't use a heater core for my climate, so I just hooked the HX directly to the water pump, bypassing the van's heater.. Even with the funnel and my bleeder valve on the HX, it took a while..

Good luck!

 

[Bryce C]

Amazon product
View: https://www.amazon.com/OEMTOOLS-87009-No-Spill-Coolant-Filling/dp/B01A2CQSU6/ref=sr_1_1_sspa?crid=2IRQ1DFOCVNR9&dib=eyJ2IjoiMSJ9.F5nNaC9xMOvmqIn_JRvIH1QfBxk3c9IEnKTvTNpsEE0ApIoMbGRcuo6KKOLMWamcpcZzvYjgY1qCcFa5wYncwBQYiGj2pR-RU8fQVkgPk5Wj-9FP0_4dFe8MSZt9SBpRoYrkLbVhU2a8mWHqoFZKFlUw7tF8lNOw8vOAGJAtQ4ytLb5zOFEMjlBD3Ro2XVnNAq7HZ4JgFqWqiIZu0H44CLJgx603pMGJ5PnYrk2S9ABUrL_o2Bu0SXCGVsGTrOd46Ix3AfUFMNHvqUvnNdpXp0IwdHRFlsGz9JS13FzElgY.AnqCpwteNebqfWx4uCyshgx2YNsKWqRU8ioA7fHMS2s&dib_tag=se&keywords=radiator%2Bfunnel&qid=1758937942&sprefix=radiator%2Bfunnel%2Caps%2C367&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1



I'd use this to burp the system.. You may have to rev your engine and also put the heater on while doing so.. Did you ever put a T or Y on the coolant outlet from the HX?

It takes a while to make sure it's burped.. I don't use a heater core for my climate, so I just hooked the HX directly to the water pump, bypassing the van's heater.. Even with the funnel and my bleeder valve on the HX, it took a while..

Good luck!

Thanks Nate! I did put a T with a bleeder valve on the HX. But I think I need to get one of these funnels and follow the steps you mentioned. My technique wasn't that thorough and went pretty quickly.

 

[Dwain Ray]

Well its like the doctor said, guy goes into the doctor and says every time i bend this way my toe hurts, got any suggestions? Doctor said stop bending like that and it wont hurt i don't know how you have your heat exchanger plumbed and or configured into into your cooling system. And i really don't know why you feel the need to shut off the coolant flow to it?? On frankinstien i dont have a valve to stop the coolant but on my original steamgeni i do but its left always on unless i need to clean with cold water. So in closing if everything works fime with the heat exchanger heating than leave it that way. Your not going to wear it out.if you have any fluctuations while it's open(on) then i would be looking for a pocket of air still in the cooling system. But if it stays normal i would say then its in the plumbing meaning when you close the valve(turn it off) coolant in the system isn't going where it's supposed to.below is a diagram of my coolant flow and heat exchanger taps

 

[Bryce C]

That's a good call, if it works fine open then leave it open!

I didn't read it on Google AI originally, I think it was mentioned briefly on one of Hydramasters maintenance videos. But they recommend leaving the coolant valve closed while driving as to not overtax the engine coolant system. I assumed they meant it would overwork the water pump but I never thought about it much and just closed it every time I drive. Anyways this came up on Shmoogle AI for what it's worth:

"Based on information found in HydraMaster manuals and forum discussions, you should never leave the coolant flow open while driving, as
this is a potential cause of overheating. The HydraMaster CDS (Clutch Drive System) is designed to operate only when the vehicle's parking brake is engaged, and the control system should shut off the unit if the van is put into motion.
Here is a breakdown of why this is important and what can cause it to happen.
Risk of overheating

The HydraMaster CDS uses the host vehicle's engine and coolant system to operate.
When the unit is on and running, it places an extra load on the vehicle's engine and cooling system...."

 

[Dwain Ray]

My engine temp in my van has been fluctuating a bit. 80% of the time it is normal, reading 210 on the gauge on my dashboard. However 20% of the time it fluctuates up to 220 to 225 then comes back down to 210. It isn't a matter of whether I am stopped/idling or cruising at highway speed. It does it in both situations seemingly equally.

Then today I just left the ball valve to my tm heat exchanger wide open while driving and the van engine maintained a consistent 210 the whole day without a single fluctuation. I'm often worried about the engine overheating when I run the tm for hours..

If you look closely at the diagram and can read / picture the flow youll see that my system is paralleled. A paralleled system can be closed off whereas if it were in series it couldn't be shut off without effecting what ever else is up or downstream

 

[Dwain Ray]

That's a good call, if it works fine open then leave it open!

I didn't read it on Google AI originally, I think it was mentioned briefly on one of Hydramasters maintenance videos. But they recommend leaving the coolant valve closed while driving as to not overtax the engine coolant system. I assumed they meant it would overwork the water pump but I never thought about it much and just closed it every time I drive. Anyways this came up on Shmoogle AI for what it's worth:

"Based on information found in HydraMaster manuals and forum discussions, you should never leave the coolant flow open while driving, as
this is a potential cause of overheating. The HydraMaster CDS (Clutch Drive System) is designed to operate only when the vehicle's parking brake is engaged, and the control system should shut off the unit if the van is put into motion.
Here is a breakdown of why this is important and what can cause it to happen.
Risk of overheating

The HydraMaster CDS uses the host vehicle's engine and coolant system to operate.
When the unit is on and running, it places an extra load on the vehicle's engine and cooling system...."

If the valve is open more coolant is flowing thru the system to absorb and distribute the heat. In the old days before fan clutches and shrouds if you drove thru the desert you turned on the heater to have a little extra cooling for your engine. So if you have 2 extra gallons of coolant in the system you now have that much more cooling capacity

 

[Bryce C]

If you look closely at the diagram and can read / picture the flow youll see that my system is paralleled. A paralleled system can be closed off whereas if it were in series it couldn't be shut off without effecting what ever else is up or downstream

From the diagram it looks like one HX in your setup receives coolant from the inlet side of your engine, and the other HX receives coolant from the outlet side of your engine. And yet each HX flows into the other HX directly. Its like a big engine coolant party you have going on there Dwain-o. Forgive me I don't understand the difference between parallel and series setups. I should because I learned about that in DC electrical when I was setting up solar panels on few RVs and a cabin. Maybe that was completely different though...

 

[Bryce C]

If the valve is open more coolant is flowing thru the system to absorb and distribute the heat. In the old days before fan clutches and shrouds if you drove thru the desert you turned on the heater to have a little extra cooling for your engine. So if you have 2 extra gallons of coolant in the system you now have that much more cooling capacity

That makes good sense to me. You build way better truckmounts then them, and your my bud, and that simply makes sense, so I trust your advice on the matter. But this is what Hydramaster says about it...

 

[Dwain Ray]

No it recives heat from the upper radiator hose going from the engine to the radiator and it returns spent coolant back into the engine thru the heater hose in

 

[Dwain Ray]

Like i said i don't know how your system is plumbed. Ive never had to shut off my coolant on any pto ive had. I dont think cleanco or butler even have a valve to shut it off. (The diagram i sent you is cleanco with no valve mentioned)
If they say shut it off id call them and ask how important it is to do that. It seems to me that coolant flow is more critical when the van is stationary that when moving. From what trouble shooting you have explained according to you valve open temp fine valve closed temp varies. And that and how my machines run is all i have to go on to base a recommendation

 

[Dwain Ray]

Amazon product
View: https://www.amazon.com/OEMTOOLS-87009-No-Spill-Coolant-Filling/dp/B01A2CQSU6/ref=sr_1_1_sspa?crid=2IRQ1DFOCVNR9&dib=eyJ2IjoiMSJ9.F5nNaC9xMOvmqIn_JRvIH1QfBxk3c9IEnKTvTNpsEE0ApIoMbGRcuo6KKOLMWamcpcZzvYjgY1qCcFa5wYncwBQYiGj2pR-RU8fQVkgPk5Wj-9FP0_4dFe8MSZt9SBpRoYrkLbVhU2a8mWHqoFZKFlUw7tF8lNOw8vOAGJAtQ4ytLb5zOFEMjlBD3Ro2XVnNAq7HZ4JgFqWqiIZu0H44CLJgx603pMGJ5PnYrk2S9ABUrL_o2Bu0SXCGVsGTrOd46Ix3AfUFMNHvqUvnNdpXp0IwdHRFlsGz9JS13FzElgY.AnqCpwteNebqfWx4uCyshgx2YNsKWqRU8ioA7fHMS2s&dib_tag=se&keywords=radiator%2Bfunnel&qid=1758937942&sprefix=radiator%2Bfunnel%2Caps%2C367&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1



I'd use this to burp the system.. You may have to rev your engine and also put the heater on while doing so.. Did you ever put a T or Y on the coolant outlet from the HX?

It takes a while to make sure it's burped.. I don't use a heater core for my climate, so I just hooked the HX directly to the water pump, bypassing the van's heater.. Even with the funnel and my bleeder valve on the HX, it took a while..

Good luck!

I used a vacuum system to fill my coolant system