M-1009 heater hoses and thermostat

[Greasy]

In the next few days I will be changing out my leaking heater hoses and thermostat (while i'm there). Currently my 09 is at a friends ranch, my question is what size heater hoses and length do I buy? Secondly what temp thermostat do I purchase? Living in the central valley of California it get HOT (102 today) but not much freezing in winter (no snow). On fleebay there are NOS surplus thermostats are 180, the facts page states 190. Which one do I choose? (Yes, I did search this forum and in the facts thread).

Thank you in advance.

 

[cucvrus]

I always buy 3 ft of 5/8" and 3 ft of 3/4" and the 190* thermostat. I also always use an impact to take the thermostat housing off and while in there I change the coolant cross over gaskets on the coolant manifold. Do all 4 2 in the front of the heads and 2 in the back of the heads. Good Luck.

 

[Greasy]

I always buy 3 ft of 5/8" and 3 ft of 3/4" and the 190* thermostat. I also always use an impact to take the thermostat housing off and while in there I change the coolant cross over gaskets on the coolant manifold. Do all 4 2 in the front of the heads and 2 in the back of the heads. Good Luck.

Thank you CUCVRUS for the advice. I will do what you suggested and change all the gaskets while the cooling system is drained. Maybe "Flush" the back of the heads while the covers are off.

 

[cucvrus]

Let me clarify. Take the 2 M10 15MM hex bolts out of the thermostat housing crossover first with an impact. that always makes it easier and I never tore the threads out with an impact. That shock breaks them loose easier and without taking the threads out and breaking the manifold. Be Safe.

 

[Greasy]

Let me clarify. Take the 2 M10 15MM hex bolts out of the thermostat housing crossover first with an impact. that always makes it easier and I never tore the threads out with an impact. That shock breaks them loose easier and without taking the threads out and breaking the manifold. Be Safe.

Makes sense, I will add anti-seize to the threads going back together. Steel bolts in an aluminum housing close to water = No bueno

 

[nyoffroad]

Makes sense, I will add anti-seize to the threads going back together. Steel bolts in an aluminum housing close to water = No bueno

While you have the never seize out make sure you put some on the heater core nipples, that makes it much easier to remove in the future. Also to remove the seized on hose from the brass nipples use a sharp knife or razor blade to slice the hose lengthwise and peel it off the nipple, that keeps the nipple from twisting and leaking inside the truck!
While your doing all this don't stop at just the heater hoses and T-stat go ahead and change the upper and lower rad hoses and the belts too. It's a bit more money and not much more work but will give you years of peace of mind.

 

[cucvrus]

That's what these tools are made for. Once you use them you will never go back to yanking and cutting. Makes stubborn hoses a breeze. Be Safe.
https://www.justparts.com/Auto_Parts/Snap-On-Tools-Radiator-Hose-Remover-2-Piece-Set-Kit-Hook-Pry-SGA1714B---SGA1713B/33517263?BackToUrl=http%3A%2F%2Fwww.justparts.com%2FAuto_Parts%2F90-91-Honda-Prelude-OEM-Left-Side-Bumper-Turn-Signal-Light-Stock-Blinker-Lamp-KA%2F32827237

 

[Greasy]

While you have the never seize out make sure you put some on the heater core nipples, that makes it much easier to remove in the future. Also to remove the seized on hose from the brass nipples use a sharp knife or razor blade to slice the hose lengthwise and peel it off the nipple, that keeps the nipple from twisting and leaking inside the truck!
While your doing all this don't stop at just the heater hoses and T-stat go ahead and change the upper and lower rad hoses and the belts too. It's a bit more money and not much more work but will give you years of peace of mind.

I appreciate the advise nyoffroad, hit a little roadblock with the thermostat. My local parts house (I buy local when I can) could not get a 190 therm, only showed 180, 195, 205 (?), etc. Ended up going through a "South American River" named company to get a AC delco 190 therm. My local parts house had all the gaskets and hoses I needed.

 

[panama]

I always buy 3 ft of 5/8" and 3 ft of 3/4" and the 190* thermostat. I also always use an impact to take the thermostat housing off and while in there I change the coolant cross over gaskets on the coolant manifold. Do all 4 2 in the front of the heads and 2 in the back of the heads. Good Luck.

Does that mean the heater hoses are different sizes? Mine are old and caked with dirt but they look to be the same size.

 

[cucvrus]

Yes one is 5/8" and one is 3/4" you can see the difference on the heater core connections. The 3/4" goes to fitting on the right passengers side of the radiator and the 5/8" goes to the coolant crossover manifold connection. Always use new clamps. Avoid trouble. Take Care and Be Safe.

 

[cucvrus]

Not sure if you can see my heater hose routing. But get them out from under the battery box. That is a poor place for them. It carries over from the civilian models and was just the old standard. This way they are better supported and seem to set nicer.

 

[panama]

Not sure if you can see my heater hose routing. But get them out from under the battery box. That is a poor place for them. It carries over from the civilian models and was just the old standard. This way they are better supported and seem to set nicer. View attachment 808290

I see what you did with them. Mine are still under the battery tray. I will reroute when I replace with the new radiator.

 

[Sharecropper]

Not sure if you can see my heater hose routing. But get them out from under the battery box. That is a poor place for them. It carries over from the civilian models and was just the old standard. This way they are better supported and seem to set nicer. View attachment 808290

Rick - I really like your pegboard set-up on the wall and how neatly you have arranged all your precision tools. I wish I could get mine looking that good.

 

[cucvrus]

GOODFELLAS- Never Bust a Wise Guy's Chops. Now go home and get your shine box Sharecropper.

 

[GreggVA]

Not hijacking but adding content...

Bottom Line Up Front -would a 195 degree thermo make your coolant light stay on

~~~~~~~~~~~~~~~~~~~~~~~~~~

My Engine Coolant Temperature Light (shown as number 4 on page 2-2 of TM 9-2320-289-10) has been lighting up and staying on when running the engine. I ran the engine in the driveway and have got hot heater hoses, hot lower hose and relatively cool top radiator hose when the light comes on. I shut the engine down before seeing if the top hose would eventually get hot with the thermostat opening. I figured it was a stuck thermostat.

I pulled the thermostat housing and tested the thermostat in a pot of water on the stove and it opened in boiling water. It is a 195 degree F thermostat versus the 190 [B]cucvrus[/B] recommends (who I trust explicitly). I do think I heard a tiny click when it opened and it may stick a little bit when manually opened but it certainly opens on its own in boiling water.

Do you think the 5 degree difference could make the light stay on? I am ordering a 190 degree anyway.

Part numbers I have found:

ACDELCO 13255
STANT 14429
GATES 33924
GM Original Equipment #14077122

 

[chevymike]

You likely have a bad sender or wiring issue. I don't think that light comes on until the 220* range. 195 is normal and I wouldn't blink much until it was in the 210+ range.

 

[GreggVA]

You likely have a bad sender or wiring issue. I don't think that light comes on until the 220* range. 195 is normal and I wouldn't blink much until it was in the 210+ range.

Appreciate the response. You don't happen to have a good part number/source for that sender. Thinking this is the one on the front of the engine drivers side next to the first glow plug. I see a

ACDELCO 2134792 {#88865045} Sensor; GM Original Equipment 1/2 Inch x 14 Thread; With Gauge

and then the one below which is I think the one on the passenger side near the firewall lower on the engine.

 

[cucvrus]

That's an expensive temperature sending unit. I have a used one I'll sell for 1/2 that price. Genuine GM. WOW.

 

[GreggVA]

So TM9-2320-289-20P FIGURE 46. ENGINE OIL PRESSURE AND WATER TEMPERATURE SENDING UNITS shows item 1 in the figure to be:

- 1 PAOZZ 11862 25037177 TRANSMITTER,TEMPERA

The 25037177 is the GM part number which converts to an ACDELCO GM D1863B.

This converts to an O'Reilly TS81

 

[cucvrus]

So TM9-2320-289-20P FIGURE 46. ENGINE OIL PRESSURE AND WATER TEMPERATURE SENDING UNITS shows item 1 in the figure to be:

- 1 PAOZZ 11862 25037177 TRANSMITTER,TEMPERA

The 25037177 is the GM part number which converts to an ACDELCO GM D1863B.

This converts to an O'Reilly TS81

View attachment 809433

WOW what a deal. Autozone does price match. HA HA.