Thermostat?

[jmsmith76]

Can anybody tell me what this thermostat is out of?

While flushing coolant today I found this in my 96. looks nothing like the one I bought for a 96 and the 96 thermostat does not fit in the water outlet on my truck. it won't sit all the way down in there. thanks in advance for any help...

 

[jmsmith76]

update. .. a 95 thermostat fits in there fine. still doesn't look like the one that came out of it so I don't know what the deal is. can I safely run the 95 thermostat?

 

[backwoodsboy]

What is the build date of your engine? 1994.5-1995 had a short stem thermostat, while 96-03 had a long stem.
Good news for you is you can run an International 203* t-stat.
Whatever you do, don't run a thermostat from Napa or similar parts house. Stick with OEM.

 

[jmsmith76]

Not sure on the build date of the engine and it's at my buddy's house at the moment so I can't check the serial number. That's where I've been working on it. I know the truck is 11/95 based on the door jamb sticker. I will mention that the belt on there is a 1223 which is the same size as a 2001. Most everything else I've done to the engine, I used 96 parts with no issues.

Right now I'm going to have to put a parts store thermostat in there to get the truck back on the road. I can swap it out soon though. I had ordered the Dieselsite 203* t-stat. After looking at pictures of the 94.5-95 water pump, I'm pretty sure that's what I have. Mine looks just like it. I just don't know about what thermostat was in there. I haven't found a picture of any 7.3L thermostat that looked like it.

 

[jmsmith76]

I'm just a little wary to use a 95 thermostat because of the things dieselsite mentions about the short stem thermostats.

"Although International still uses a 203° thermostat in some applications and that thermostat is available at most auto parts stores, it is the wrong part for the 1996 - 2003 Powerstroke. DO NOT USE THIS! It has a shorter shaft and will not shut off the internal pump bypass. This will cause inaccurate coolant flow direction through the engine. This IH version thermostat mentioned is available by calling us.

The thermostat in the Powerstroke not only controls operating temperatures, but properly directs the flow of coolant through the engine. As the thermostat opens, it proportionally closes the bypass. With the thermostat fully open, the bypass is mostly closed, and vice versa. With the International (Pre-96 Ford) thermostat, this cannot be controlled properly because of the shorter bypass stem. The shorter stem of the IH(pre-96 Ford) thermostat allows the thermostat to be fully open while the bypass is fully open. This means the coolant can travel in any direction available -- whatever direction it chooses. It can either travel through the radiator or simply make the shorter, less restrictive path back through the front of the engine. This will cause uncontrolled overheating in the back cylinders of the block, with absolutely no signs of danger showing on the water temperature gauge in the cab. It is possible that the back of the engine can have no coolant flow at all yet the thermometer in the outlet of the water pump shows all to be normal. Multiple things can happen at this point. Cylinders can seize, freeze plugs can fall out and other normal symptoms of an overheating engine may occur. Worst case is a blown motor and it won't be covered under warranty."

 

[Jennifer@Dieselsite]

It DOES look like a short little guy in your picture... but I can't be too sure. The only way to know which thermostat to use is to identify your water pump. I wouldn't recommend build date because a previous owner could have swapped pumps.

If you have a 94-95 the one you bought from us won't even fit (it'll just be too big).
If you have a 96-03 the one you bought from us will fit perfect!

I believe we measured this recently: on the water pump (96-03) from the edge where the lip of the thermostat would sit down to the bypass it was 2.2 inches. I'm guessing anything less would make it earlier?

 

[jmsmith76]

All I can figure is that it's a 95 water pump. Currently running the 95 thermostat from the parts store and will be ordering an international soon as I find one. Anybody know the part number for it? So far it seems to be running fine. Definitely runs hotter than I'm used to. Gauge sits on the M. ScanGauge says 205* when sitting at idle and when running down the road it gets up to about 212-213*. Does that sound normal?

 

[backwoodsboy]

My old International parts catalog lists it as Part # 1822649C1.
By chance does your water pump have a filter base built into the lower right corner (looking at it from the front of the truck)? I suppose it is possible that a previous owner swapped to an International water pump.

From my experience parts store thermostats aren't worth their weight in scrap. I've had issues with them not opening fully and causing high coolant temp issues. Best to swap it out for an OEM one as soon as possible.

 

[MOE]

Just put one in my 96 350 and it looks like the new one. The new one is different then the one that was in it.

1996 F350 XLT 7.3 CC 8' Bed

 

[jmsmith76]

Thanks for the part number. No filter base built into it. Here is the best pic I could get from under the truck which seemed to be the best angle to take a picture from. This look like a 95 water pump to yall? May not be a good enough picture to tell...

 

[jmsmith76]

Just put one in my 96 350 and it looks like the new one. The new one is different then the one that was in it.

1996 F350 XLT 7.3 CC 8' Bed

My old thermostat looks like your new one? Where did you get it from?

Thanks

 

[trackspeeder]

Thanks for the part number. No filter base built into it. Here is the best pic I could get from under the truck which seemed to be the best angle to take a picture from. This look like a 95 water pump to yall? May not be a good enough picture to tell...

Yes it does look like the 95 pump. Not all of the early pumps had a filter base.

 

[jmsmith76]

Cool, thanks. I'm going to order an international thermostat to replace the parts store thermostat I had to throw in there to get the truck back on the road.

Thanks for the help everyone!

 

[jmsmith76]

Well I guess that 95 thermostat was the wrong one. One of my freeze plugs sprung a bad leak today. Or is there anything else that would cause that? At this point I'm thinking about just changing the water pump out for one that I know is right since nobody knows what my original thermostat came out of.