Ok guys, I started the new GM LS6 crate engine today, I bought the computer and wiring harness from Turnkey Engines and I have two problems, #1 the engine would not start it sounds like the engine is 180 degrees out, I found the main coil connector that feeds the wire harness for the individial coils is on the opposite sides than where my LS1 is, I swapped the connectors and the engine starts and sounds great, the second problem is it is over heating very quckly, I keep bleeding the steam off and it keeps doing the same thing I have tapped the top of the pressure side of the water pump and feed it to the steam line, no luck!!!!! Here is where i'm lost! could it be the harness on the injectors is backwards? I think the coil harenss is backwards. Currently the injector wiring is Blue on the left and Green on the right, I have the the coil connectors crossed across the motor. Do you think it could be lean? it seams the heat is coming from the left bank of the motor heat temp spikes between the center two cylinders.
I will contact TurnKey Monday, maybe the wiring is causing something?
Any input?
Thanks
Chris

BURP IT, you have air trapped in there!

OK, I have burped it 15 times, I tapped the pump and ran the line to the steam bleed line. I raised the back of the car and took the front tires off and set it on the ground. Still no luck! I drained it and removed the plug in the water pump between high pressure and low pressure sides, still no luck.
What do you reccommend?
Chris

I'm a Honda guy..............

but when I had a similar problem all the LS1 guys said this was common with their engines as well.
Where did YFZ4KT go, he'd know where to burp it at to get all the air out?

Maybe he will chime in here.

The postman goes to bed early...............

Stuck T-stat.......

No, stat opens at about 195 degrees and flows out of the cap.
I will look first thing in the morning.
Thanks for the input tonight.
Chris

Make sure the T-stat is not stuck partially open but if you have overflow coming out of the radiator while cap is off or see bubbling, the system is being pressurized and that most likely means by combustion gases.

If your using a thermostat you have to use the heater hose connections as well or the water will not circulate to warm up the thermostat. Cut the guts out of the center of the thermostat or get a Camero thermostat housing that is not cut for the thermostat. You just can't take out the thermostat the housing is cut for the o-ring and will leak without the thermostat. There is also a mod to block off the heater ducts in the back of the water pump, but the 1/4" hole is commonly forgot.

The LS1 install I'm familier with uses a pressurized burp tank. We cracked all the burb tank connections to bleed them.

You can tell if air is in the system by checking the temp of the upper radiator hose. If its hot its moving water. If its not hot and the engine is hot then you have air in a line or a thermostat issue.

I said overflow what I meant is the ystat opened and the flow started, but i still have steam so maybe combustion gases? it's a new ls6 no little bubbles?

I removed the heater hose connections and threaded in some plugs as recommended by Butch at butches spped shop in Vegas. I installed the plug with a 1/4 hole in the back of the pump when I started this project but removed it today. Are you saying to run it without a t stat? The t stat opens and flows at about 195-200 then stands at 210 then spikes quickly. I have burped the steam lines on the front of the motor more times than I can count today and i get steam evey time.
The fans come on at 180 as designed.
I used an IR thermometer

Should i put the plug back into the pump housing and remove the stat? I have to destroy/cut it out if it's needed I think they are big $
Chris

I am not familiar with your engine but have seen drive belts routed wrong that turn the waterpump backwards or the wrong waterpump was installed and the rotaion needs to be the other way to flow.

I know it sounds goofy but that was the first thing that ran through my mind as well. Don't know anything about the LS series engines but that seems like a logical thing to check...

Make sure you have the freeze plug in the back of the water pump with a 1/4 hole drilled, and take the t-stat and snip the "legs" off it leaving only the portion with the seal left and put it back in, then loosen the bleeders at the front of the engine while you fill it with coolant again, when they start to leak tighten them,fill the system full run it then loosen them again to ensure there is no air left. If you still have problems check your radiator cap

All sounds good, the belt is correct. I will reinstall the freeze plug and snip the t-stat.
Thanks for all the help so far.
Chris

I very well could be wrong but I remember hearing the the LS6 sucks water in the top and pushes it out the bottom and the LS1 sucks it in the bottom and pushes it out the top. Your hoses could be reversed.

I'm confussed are you saying the pressure is on the bottom of the LS6? When I started this project the crank and accessories needed to be replaced with camero stuff to line up the alternator with the crank. I replaced the crank pulley, alternator bracket, idler, and water pump with camero stuff.
So the million dollar question is, I have my pressure from the top of the pump is it correct?
Chris

It's a standard hose arrangement. The lower hose off the radiator connects to the water pump.
Reverse cooling has nothing to do with hose routing.

So am I ok? the camaro pump output is on the top of the pump, right? does the motor have a problem with this?
Chris
If anyone would like to talk I can call them
702-334-1476

i have a friend who bought a car with an ls1 that had just been installed ,(luv2rail) the car originally had i believe an ls6 , his car constantly went into limp mode because it was getting hot , he took it in a nd they said the flow the radiator was backwards . i dont know all the details but this sounds similar .something about ls1 and l26 flowing the opposite , i am no expert and dont remeber the details but i would look into it. tim

i just called john , (luv2rail) he said lopers here in phoenix fixed it by reversing the hoses to the radiator , his had an ls6 before he bought it and the guy kept the ls6 and installed an ls1 , the car did overheat constantly , lopers told him that they flow the opposite direction and he was trying to push the water up the radiator in stead of flowing down and out the botom or something to that affect , i bet you have the same problem only the reverse as you went from ls1 to ls6 . john said mike kelly from lopers is who he worked with , you could call them tomorrrow . hope this helps and remember it is worth what you paid for it . lol . tim

The outlet where the T-stat is, goes to the upper part of the radiator, the inlet to the pump goes to the bottom of the radiator.

I'm confussed are you saying the pressure is on the bottom of the LS6? When I started this project the crank and accessories needed to be replaced with camero stuff to line up the alternator with the crank. I replaced the crank pulley, alternator bracket, idler, and water pump with camero stuff.
So the million dollar question is, I have my pressure from the top of the pump is it correct?
Chris

sounds like you have it backwards , tim

Here's an ls6 with hoses routed.
T-stat line goes to top of radiator.

I agree, it sound like i have it backwards. I looked at a LS1 rail to get the output/pressure side of the pump to go to the top of the radiator.

Like I said i'm using a new camaro water pump 2002 on the LS6 engine so pressure side on the t-stat or the top?
Chris

I'm the opposite of your? What water pump are you using? are you open on the t-stat (clipped out)? are you running the freeze plug wiht the 1/4 hole in the pump behind the t-stat opening?
Your picture sure helps my brain, Thanks Very Much!!!
Chris

Not my car, Ima honda guy who is gunna whoop up all over your ls6..

I just thought I would find a picture of the hose routing on a Ls6. It does appear the Ls1's are routed opposite.
In my mind the inlet to the water pump should always feed from the bottom of the radiator..If coolant gets semi-low how is the pump going to grab water off the top of the radiator, it would be air??

I beleive your correct the radiator is gravity feed coolant sould from from the top to the bottom.

Now for thw whoopin, my best friend has a turbo'd VTEC 3.5 but he's afraid of the thin pedel on the right, do you have the same problem? but seriously weight to power ratio favors you.
Chris
Looking forward to a nice run with ya.

Keep us posted on what you find out, I am very curious.

I am sure we will cross paths this upcoming season. I'll show ya what a Turbo'd 3.5 can really do...

As long as the "inlet" (if its the water pump or the tstat) goes to the bottom of the radiator then you will be OK. I hope that on of the builders jumps in here and confirms what I was saying.

Something else to check too. I had problems with my motor over heating. I thought I had the radiator full as everytime I would pull the cap off it was full. Until I did it with the motor running and found the coolant almost at the bottom of the radiator. Filled it while it was running. never had the problem again.

Are you running a t-stat or is it clipped out? are you running the freeze plug with the 1/4 hole in the pump behind the t-stat opening?
Thanks for your help
Chris

Another thing to check... The crossover head tube should be installed at the top or high side of the motor !. I installed a little bleeder valve on my ls1 crossover tube also. Ls1's are a biatch to bleed !!. need a overflow res. tank ??.

.

As far as the T-stat goes... I would clip it out or drill some holes in it. (about four 1/4" holes)
That 195 stat should be changed to a 160 at the very least.
My buddies Ls1 is clipped out and the builder of my motor clips all his out as well.

Check the timing.

Not enough advance, on setting the ititial timing could cause overheating.

Timing? it's an LS6 all computer controlled, no way to adjust it.

Call me tomorrow, we can talk 909-390-9130 Bruce

Thanks, Bruce

Ive heard about some LS motors where the only fix was to flip the radiator lines...

Ive also seen a post or two on here where a motor reseller had the head gasket backwards on one side.

But Im just a Honda guy too...

So I talked to Cory at Turnkey this morning and he said to use the freeze plug with the 1/4" hole in the water pump, not to use a t-stat and to bleed the steam from the heads.

He believes the problem was most likely I was using the T-stat and the freeze plug in combo.
I went ahead and called bruce at CMB and he agreed with Cory completely.

Both guys agree that the LS1 and the LS6 are both normal routing for the radiator line NOT reverse flow i.e. the top radiator line goes to the top of the water pump and the bottom radiator line goes to the bottom of the water pump.

Hope this help all in the future..

Thanks
Chris

Did this take care of your trouble ^^^^^^^???

Just finished testing and it seams the over heat problem is solved!
Thanks to all
Chris

BURP IT, SLAP IT, DRILL IT....WHAT THE HELL??????
TRADE IT FOR A NICE TWO SEATER JACKSON MID TRAVEL WITH A VERY DEPENDABLE 3.5 SHORTSTAR.

ORRRR YOU COULD BE BLESSED WITH A BROTHER WHO IS A MECHANICAL WIZARD......ORRRRR YOU COULD BE BLESSED WITH A BROTHER WHO"S NOT A MECHANICAL WIZARD, BUT WILL COOK.


TIMTIMTIMTIMTIMTIMTIMTIMTIMTIM

Going to start my motor this weekend and this was a great read. Good Information, I was not even aware of a freeze plug. I hope all goes well


Joe