Roller406Bu

iTrader: (1)

I have no idea what to do, I have a reman water pump, new thermo, on a 02 6.0 lq4 and it won't circulate the coolant any thru the motor....I have all camaro access. on this. I filled the radiator half full with the cap off and it wont go down any....I pulled one the hoses off the the pump where it goes to the heater core and fluid poured out...The motor gets warm very quickly and i shut it off at 210...I have a 186 thermostat on it. heres how i have the belt routed as an example..any ideas???? Could the pump be bad causing this???

LS1MCSS

iTrader: (18)

Pull the top radiator hose off, at the radiator. Fill the block through that hose and it should work. I had problems when I first started messing with the LS engines and thats usually the fix.

Roller406Bu

iTrader: (1)

i'll try that, and the ms4 in this thing sounds wicked!!

andrew69_04

iTrader: (148)

i hear you can bu a vacuum thing from autozone/parts store that works really well for removing the air out of the system. i also had this same problem and never got it fixed. put the ls1 in my 69 camaro stock. kept overheating then finally got a huge airpocket out of it and it worked great. Just swapin a a cam, and i acnt get any more air out and it keeps gettin up around 230ish and the fans wont kick on like they dyd before. ended up putting a maunal fan switch on it and it runs cool now, but it still isnt right.

76LQ9TA

iTrader: (1)

You definitely need to fill the engine through the upper hose. It also helps to have the front of the car on ramps.

67rsss

iTrader: (4)

It took us several days to burp the system. Pull the steam lines that run through the throttle body, and add a long bit of hose and raise it higher than any other point in the system while you are filling the block. This seemed to help with air removal in our build. We just kept topping the rad and off with the steam lines up high until we had coolant in the steam line, which took several days. I am certain there is a better way, because GM doesn't have several days to spend filling the coolant system. I do plan on filling the block through the upper rad hose next time, this should save a lot of time.

BonzoHansen

iTrader: (7)

Uber-N00b question, but I am still learning these motors as I prep for my swap, so bear with me.

With a SBC, all I have ever done is let it run with the rad cap off and everything would be fine. I even have a nifty little Lisle funnel adapter for the rad neck so I don’t spill anything. Would that method not work for an LS motor? I see no bleeders anywhere, so barring packaging issues that leaves the rad neck too low, I don’t see why it wouldn’t.

LS1Z28

iTrader: (18)

I use the UVIEW COOLING SYSTEM EVACUATOR .Works great and only takes 10 minutes to purge the cooling system. You can find them on Ebay.

Rodder

iTrader: (2)

All I did to mine was squeeze/push down the upper house. Then top off the coolant and repeat until it doesn't burp anymore. Pulling loose the top hose and filling through that probably would have been easier.

Oscar Will

The old iron motors had wet intakes and a completely different bunch of passages, much easier to fill & purge. When we got into the first LS1 cooling system repair back in 1997 on a Corvette we really struggled with the air-pocket problem.

G-Body

iTrader: (4)

You cannot fill it through the radiator. If you try to there will be no coolant in the block (the thermostat is in the lower hose and will not open because the only coolant that will touch it is the stuff in the rad which will still be cool while the engine overheats).

The fastest way to fill my car is through the upper hose and then I fill it through the flush T in the heater core hoses (the flush t is the highest point in the system)

Rodder

iTrader: (2)

I wonder if jacking up the side of the car with the radiator filler neck a couple of inches would make it easier to fill through the radiator. My upper radiator hose is about even with the fill neck, so I already get coolant filling the engine through the upper radiator hose when I completely top off the radiator (using one of those snap-in funnels), but it needs help burping (by moving/squeezing the upper hose).

Todd157k

iTrader: (5)

This may sound stupid, but I actually did this on my 32 ford... Is the pump spinning in the right direction?

black98ws6ta

iTrader: (77)

I usually let the motor get alittle warmer then that because if it does have air in the system shutting it down at 210 will usually not be warm enough to open the thermostat. If you get it 220-230 then **** it down it usually opens the thermo and you can fill it the rest of the way.

venomhp

iTrader: (13)

I usually just fil it up from the intake manifold and the radiator, squeezing the upper radiator hose to burp it, then i just spin the water pump pulley for about 10 minutes or until the its not burping anymore. route the belts turn it on and see where your at. its worked twice for me and just check the coolant for the next couple of days to make sure your good to go