47-55.1 Lincoln Cooling Fan

[mobileortho]

Originally Posted by leegreen

I'd look for a stuck thermostat or obstruction somewhere. A water pump that is failed so hard as to stop pumping would probably have other issues...like a seized pulley and a large puddle. It is possible the pump spit the impeller off the back, just not likely

That makes sense & is the easiest fix. I'll start with the thermostat this weekend. Thanks Lee!

[leegreen]

I think it said on the Holley site that the water neck could be clocked. It might be as simples as the actual thermostat vent hole being at the bottom so there is a bubble in the housing and is no water flow around the thermostat body to heat it up in time

[mobileortho]

Crossed the thermostat off the list, it works fine. Tested it this weekend.

[dsraven]

the LS engine coolant flows through the rad and butts against the closed thermostat (until it opens) at the engine coolant intake of the water pump then, when the engine heats up, coolant flows. you wouldn't see flow in the rad until this point. the old small block way was flow through the thermostat from the engine outlet side, not the intake side.
either way, no flow through rad until thermostat opens. flow through heater hose all the time.
check out this link for an in depth look at cooling system, steam lines etc. LS specific
http://www.billavista.com/tech/Artic...ble/index.html

[mr48chev]

That link is quite and education in cooling and especially in LS cooling.

[dsraven]

yup, it is a good read for somebody who is building and is unfamiliar with how the LS system works.
hopefully it will help somebody

[Hcb3200]

Pull the thermostat. out leave it out
Put the lower hose back on and stick a garden hose in the fill of radiator.
Take off the top fill hose and leave over top of radiator. (tie it off so does not fall into mechanicals)

Fire it up let it run and see how much flow your actually getting thru the system. it should hardly get up to operating temp with the constant flow of cold water in system.

That will tell you a lot. you can even measure gallons per minute in a five gallon bucket.

[mobileortho]

Originally Posted by Hcb3200

Pull the thermostat. out leave it out
Put the lower hose back on and stick a garden hose in the fill of radiator.
Take off the top fill hose and leave over top of radiator. (tie it off so does not fall into mechanicals)

Fire it up let it run and see how much flow your actually getting thru the system. it should hardly get up to operating temp with the constant flow of cold water in system.

That will tell you a lot. you can even measure gallons per minute in a five gallon bucket.

Great idea. I like the idea of trying small things first & checking them off before tackling the bigger stuff. I plan on running steam port vents on all four corners & moving the hose from the water neck housing on the pump to the upper radiator hose to see if that make a difference as well. Fingers crossed.

[mobileortho]

The saga continues. relocating the steam vent had zero effect. I stumbled onto a Scoggins Dickey video discussing the differences in the thermostat housing and the importance of using the right housing or it could lead to overheating issues. Well...I didn't use the housing that came with the Holley kit because the opening point directly into the fender so I swapped that for a swivel style to improve the angle. I'm wondering if this could be the issue. I can't the one that came with the kit so I ordered a replacement. I'll see if this helps.

[Hcb3200]

Originally Posted by Hcb3200

Pull the thermostat. out leave it out
Put the lower hose back on and stick a garden hose in the fill of radiator.
Take off the top fill hose and leave over top of radiator. (tie it off so does not fall into mechanicals)

Fire it up let it run and see how much flow your actually getting thru the system. it should hardly get up to operating temp with the constant flow of cold water in system.

That will tell you a lot. you can even measure gallons per minute in a five gallon bucket.

DID you do this?

And can you repeat the temp that its running at under normal driving conditions and what temp its getting to idling with everthing hooked up like normal?

[dsraven]

can you post an underhood pic of your set up that shows the hoses connected etc? curious how things are laid out under there, size of hoses, if there are sharp elbows etc.
doing the flow test would help give you an idea of flow capacity without the thermostat
normal to have no coolant flow through rad until thermostat opens
do you have a heater or are you running a bypass loop at the water pump end so there is coolant flow through the block when the thermostat is closed? this helps reduce hot spots around cylinder heads and steam production when the thermostat is closed.

[leegreen]

what DSraven said, you need flow through the heater hoses for LS. If you are running a heater does it have a coolant shutoff and is it open? If one of those old thermostatic flow controls maybe confirm it is open or bypass it.

haven't watched that thermostat housing video, but ignorant of that I'm not sure how a housing could have much impact unless it restricted flow or allowed you to get the thermostat in upside down so it did not heat up properly.

[mobileortho]

Originally Posted by Hcb3200

DID you do this?

And can you repeat the temp that its running at under normal driving conditions and what temp its getting to idling with everthing hooked up like normal?

No, got halfway through & realized I didn't have a gasket to seal it off. Picked up so gasket material so I can make a temporary one & will try again this weekend.

Originally Posted by dsraven

can you post an underhood pic of your set up that shows the hoses connected etc? curious how things are laid out under there, size of hoses, if there are sharp elbows etc.
doing the flow test would help give you an idea of flow capacity without the thermostat
normal to have no coolant flow through rad until thermostat opens
do you have a heater or are you running a bypass loop at the water pump end so there is coolant flow through the block when the thermostat is closed? this helps reduce hot spots around cylinder heads and steam production when the thermostat is closed.

No sharp edges or weird angles, everything flows pretty straight. I am running a heater. I do have a bypass hose that I'm going to hook up when I remove the stat this weekend to check flow as mentioned above by HCB 3200.

[Hcb3200]

since your pulling it to put in a gasket.
Do the flow test with straight water. makes less of a mess and you are not running it long enough to boil over with that cold water it won't over heat.
Run it idling see what flow is and run it about 1500 and see what flow is.

Then drain and hook all up normal and fill with proper fluid mix assuming the flow is normal and has not sent you off in a issue to troubleshoot.

[dsraven]

You can also run it with no stat and see what flow you have through the rad, then pull the upper hose and do the flow test into a bucket. Like said above. When done and sorted pull the block drains to dump as much water out as possible.

[mobileortho]

So I think I figured it out. Took out the stat and used a bypass on the heater hoses as suggested. Got good flow through the water pump, temp held steady around 185ish. Looks like there's a bad valve in the heater that's restricting flow. I'll put the stat back in & leave the bypass hooked up untill i get around to fixing the heater. Dont need it now anyway! I appreciate all the advise! This LS definitely has a learning curve!

[Hcb3200]

And for those of you following along here are some cutaway pics and a flow thru thermostat.
Since the thermostat is located at the bottom of the path and cold fluid flows down. if there is no flow through the thermostat and around it will take longer to open even when the top of the engine is at temp. thus the engineers made the pump flow thru the heater core at all times. Because modern heat and AC in modern cars just changes where the air flows and not the flow of the coolant in the core. So if your using older cores or ones that use a vacume valve to open and close you need to make sure some flow is happening. to solve this when you have no heater core the LS swap guys just put in a loop hose between the pump ports. And others will just cap it and let it get hot and sooner or later open. (in my opinion a bad idea but a lot of guys will swear it works ok) another option is a flow thru type of thermostat the example below has a center opening to allow a slower flow at all time and then opens normally to give full flow. either way its good the OP figured it out.

[dsraven]

yup,without trying to step on anybodies ego, if there isn't a coolant flow loop then you're prolly gonna have issues. whether you know it or not. use those heater hose connections for a simple loop of hose if you don't have a heater/