5.3 LS swap: cooling issue (formerly a kinked upper hose) (2 Viewers)

[Vandy321]

Edit: fixed the upper hose kink, still have a cooling is. Not sure if this is due to calibration of the toyota temp sensor/dash gauge and the actual LS thermostat. The dash guage often gets to 3/4 or slightly higher, but I dont know what temp that is on the toyota gauge. Is mid range 180 deg? Going to IR thermometer the lower hose and see what coolant is actually running on it's way out to radiator and go from there. Maybe as simple as needing to calibrate?


Original post: Anybody have a good way to solve the 5.3L LS swap with the upper radiator hose being kinked as it comes off of the water pump, the intake is sitting right on top of it causing a bend/kink.

Coolant is still flowing, but seems reduced, over 50% going into the radiator. Seems the water pump is working overtime due to thar and temps are slightly higher than they should be. Not overheating, but definately running warm (t-stat is cycling, so it's not that) and want to address it.

I did buy some 2" ID steel braided fuel pump fill tube that I'm going to try and use as a crush proof brace over the radiator hose in that spot...just seeing if anyone had a better idea.

 

[White Stripe]

You can use a piece of exhaust pipe of required diameter and crush a section into a oval if u need to using a vice or press.

 

[Mixelplix]

Back in the day I remember stainless steel springs being inserted into radiator tubes to keep them from collapsing in tight bends.

I'm sure they're still around.

 

[shocktower]

Back in the day I remember stainless steel springs being inserted into radiator tubes to keep them from collapsing in tight bends.

I'm sure they're still around.

I have used a steel spring in a small coolant hose, just find a correct diameter spring and use it to support the hose walls and still get your bend

 

[Eagle80]

I'm a radiator shop owner and agree with a post above- go to an exhaust shop and they can bend whatever you want, whatever diameter you want and much stronger than a spring. Hoses can still collapse with a spring. Also have the shop flange the ends so no leaks occur at the hose clamps.

 

[Vandy321]

I picked up some fuel filler hose, 2"...its some thick/stiff rubber that is steel braided inside. I'm going to try and split it and slide it over the standard molded hose...will report back. Next stop is the muffler shop...this was just the cheaper, DIY version.

I am concerned however that if I get something crush proof that the I take will no longer screw down in place...

 

[Vandy321]

Would ya'll expect that this is the culprit for the truck running hot? It's got a fairly new 4 core alum radiator and a recent t-stat. Havent hooked anything up yet to check temp, but the factory Toyota (180 degree guage) is sitting at 3/4 or higher around town...

Re-routing that upper hose for better flow, but wondering if the original toyota t-stat and guage are 180 degrees, if the LS motor at 200 or 190 degrees explains why its reading hot?

I just dont recall the truck warming up past halfway on the gauge on test drive.

 

[thatcabledude]

What pump is that? Looks like the one with the tall and long neck. If so, swap to a 2010+ truck pump.

 

[thatcabledude]

My truck:

 

[thatcabledude]

A comparison:

 

[Vandy321]

Fixed the kink with a hard 90. Now the hose just has a slight oval, but no real restriction in flow.

Still running hot. Truck has the toyota temp sensor hooked up to the 5.3l motor. Unsure what temp Thermostat is in the 5.3, previous owner swapped it. My temps are rising to about 3/4 or slightly higher on the dash, AC is cutting out at that point. Gauge shows warmup (needle to needle to middle) very quickly, within 2 mins of driving or so. Is this easily fixed with a 180 deg thermostat since thats what the toyota temp sensor thinks is mid range on the guage?

Or do I have a seperate cooling issue? Truck has an aluminum 4 core radiator. I guess I should check the fan for operation as well.

Just curious if the 180 thermostat makes sense and it would show running hot on guage with a 187 deg thermostat reading on a toyota temp gauge.

Temps were in the 40s today, around town driving, seems to just to 1/2 on temp gauge pretty quickly. Then 10-15 min of driving and it goes to 3/4 or slightly higher and wont really recover to mid range. This happens on local trails, around town and on freeway. Never hits overheat line, but def runs 3/4 hot

Do I need to just run an IR gun on the lower hose and find a temp? Then maybe calibrate the dash gauge to the normal operating temp of the LS?

 

[aktundra]

I posted a similar question of translating the OEM gauge to actual temps after my LS swap. (You can probably pull it up with a search, and get some details)

Best advice I received was to get a cheap, simple blue tooth OBD II reader, and the tourque app. I’m still using the free version of the app, since I’m only using the temp & GPS speedo

 

[Vandy321]

Do any of those bluetooth OBD II sensors work with torque? Just on amazon they range from $15 to $100...you mind sharing what you picked up?

 

[White Stripe]

Yes I use a blue tooth reader from amazon, I just got a 15 dollar one that had good reviews and use the torque app and use live data to verify engine temps.

 

[thatcabledude]

Maybe you have a air pocket?

You need to see the what the temps really are. The Toyota gauge ain’t worth a crap for that. When I was burping my system for the first time (it was a pain) I saw 225 with HPTuners on laptop before the cruisers gauge went up to red.

 

[Mark3406e]

Mine is swapped, even in AZ I never get over 1/2 gauge on the Toyota cluster . They run about about 195 consistent which is just under half on the cluster.

I would make sure you don’t have a air bubble they are hard to purge if you didn’t add a surge tank that back fill is. I have swapped two and that was a issue in the first one.

Take the heater line off the valve on the firewall and see if it dumps coolant if not back fill it through there .

 

[Vandy321]

Maybe you have a air pocket?

You need to see the what the temps really are. The Toyota gauge ain’t worth a crap for that. When I was burping my system for the first time (it was a pain) I saw 225 with HPTuners on laptop before the cruisers gauge went up to red.

Just drove for 20 mins, around town, 40 deg outside. Cooling fan was running. Bottom radiator hose (with thermostat in it at bottom of water pump) is cold to the tough.

I understand this water pump sends coolant from bottom hose to radiator? Upper hose reads 134 from radiator to upper inlet of water pump. Bottom hose connected to thermostat reads 84 deg...cold to touch. Assuming my thermostat has failed closed and truck isnt overheating due to outside air temps being low?

 

[thatcabledude]

Water pump outlet is the top.

 

[Vandy321]

Water pump outlet is the top.

Even with thermostat on the bottom?

Pic attached of the water pump. If that lower hose is cold and truck is getting hot...it that a bad thermostat or an air lock or clog in the lower radiator?

Upper hose reads 134 deg. Radiator is a new 4 core aluminum. Fan was running, not sure why the thermostat wouldnt have been open and that lower hose should he hot, no?

 

[thatcabledude]

Even with thermostat on the bottom?

Pic attached of the water pump. If that lower hose is cold and truck is getting hot...it that a bad thermostat or an air lock or clog in the lower radiator?

Upper hose reads 134 deg. Radiator is a new 4 core aluminum. Fan was running, not sure why the thermostat wouldnt have been open and that lower hose should he hot, no?View attachment 2113019

Here’s a good diagram of LS water flow:

Your upper hose. Is it at any point higher than the top tank of the rad?