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Coolant Crossover line is leaking. Part has been DISCONTINUED.. .Suggestions?

redheadedrod

SM 2017
PM 2015
Full Member
Joined
May 15, 2011
Messages
3,187
Location
Muskegon, MI
So it looks like the problem that was loosing me all of my coolant wasn't the cracked heads although those did certainly need to be changed...

From the look of coolant all over the top of the motor behind the throttle body I have a pin hole in the cross over pipe. The pipe is very rusted and the gaskets were changed when the rebuilt heads were installed. When looking for the replacement apparently Dorman has discontinued making the part and no one has it in stock that I have checked with.

Performance shops have replacements for them but apparently each LSx engine is a little different.

Has anyone here had to change these lines on their trucks? If so what did you use?

I am in process of changing out all of the rubber hoses too but from what I have seen so far these lines are important to make sure the heads are fully free of air and prevent hot spots in the heads. Some have tied the rear ports to the front ports to help balance the coolant flow between heads even further but I don't fancy pulling the intake manifold off again to do this.

So does anyone have a solution they have tried and works?

Thanks!

If I find one I will share the information here.

Rodney
 
Make it up with 1/4 in. copper and fittings.  (y)
 
Look here, they have the fittings to make up your own or kits that may fit yours..



https://www.summitracing.com/search?SortBy=BestKeywordMatch&SortOrder=Ascending&keyword=LS%20coolent%20crossover
 
Thanks, I did end up ordering a kit. They had a front kit with block off blocks for the back part for $99 and free shipping or buy a kit that doesn't have the adapters then buy two adapters which was $88 with shipping... Since I would loose the back block offs and would never use them I went the $88 route. If I decided to pull the intake to redo the rears I would go with the 4 corners kit.


So one of these:
https://www.summitracing.com/parts/tfs-306sb600k          $39.97 at the time of this posting

and Two of these:
https://www.summitracing.com/parts/tfs-30600611          $18.97 each at the time of this posting

We will see how well this works...  Could have gotten a cheaper kit that just connects the two sides but from what I have read the venting is an important part.
Will still replace the remaining hoses to prevent other issues but hopefully this will stop the coolant leak on top of the engine. When looking at the tubing configuration you could really see the coolant standing out on the top of the engine. With some liquid coolant still there along with the gooey green stuff left behind after drying. (Using Peak high mileage coolant which is green but has similar specs to dexcool)

Again thanks for the responses.

Rodney
 
Well frustrated so gave up for the day. Pulled off the 4 coolant lines I have ordered to replace and found something interesting.

Looks like the coolant lines that go to the TB go there for no reason. The TB connection is just a pass through connection...
Will bypass the TB when I get the chance.

And think I found the reason for the leak. Looks like these rebuilt heads must have had a stripped or broken bolt in the coolant cross over line as there is a helicoil in the head and it is sticking out slightly. It looks like it is sticking out enough to block the bolt from pulling the line in all of the way.

These trickflow adapters appear to be crap. They are not sealing up against the heads on either side. Going to try blowing out the hole to insure no crude is preventing the bolts from going all the way down but not sure how to deal with the helicoil yet.

Rodney
 
The coolant line going to the TB is mostly for cold weather operation, summer time it's not really needed.

The first thread of the helicoil may be able to be pried up a little and a small bit cut off.

Yes, make sure the bolts aren't bottoming out so the adapters can seat properly.


Good luck
 
Hard to believe that the coolant just going through that line will do much to heat up anything. The engine would be warm on its own much quicker than that little coolant line would do anything.

The Trick Flow fittings don't seal very well but going to see if it is because I didn't push the Oring on all the way. I just got it on there and figured installing it would push the Oring further. Will try blowing out the hole and see what that does. If not then I think I have some washers small enough to raise the bolt so it will tighten down.

We shall see... Ordered the rest of the hoses from Rockauto and will take a week to get here... May ditch this trick flow stuff and grab a different type of crossover now that I know it doesn't really need to go to the TB. Reminded me that I did a similar bypass on my Caprice and saw no ill effects even starting up in -30F weather.

Rodney
 
So the Trickflow adapter pieces were junk. I bought some from R&C racing I believe? Earls fittings would also work but the Trickflow kit came with 4AN fittings where the Earl fitting came with 3AN fittings. 

The Helicoil on the drivers side was very loose and I ended up pulling it out.
Ordered a Big-Sert kit which is a more solid repair setup but on the front drivers side head I have little room to stick my drill in there...

In process of removing the Bracket for the alternator and power steering pump. I have the alternator removed and three of the bolts holding the bracket in place. Looks like there is one more bolt under the steering pump I need to get to. If I can just unbolt the bracket and let it move forward slightly I should have enough room to work on the steam vent thread hole. I already installed the adapter and some of the plumbing on the passenger side. The threads looked a little rough but they held fine.

Hoping that there are only 3 bolts holding on this bracket? Looks like I might have to remove something to get to that bottom bolt...

What a PITA... This thread repair piece looks like it should be easy to use though. I just have to insure I don't go too deep and drill through into the head. A piece of tape on the drill bit as a guide hopefully will do it...

Anyone know for sure since I removed the alternator already if there are just 4 bolts I need to remove then I can move this bracket? I don't need to remove the bracket completely to get to the hold but if I wanted to remove it completely it looks like I have to pull the steering pump pulley and unbolt it from the bracket which means pulling the fan shroud and fan...

 
Unfortunately you have to remove the power steering pulley to get to one of the bracket bolts.
 
Well I was able to remove the bottom bolt and wedge the bracket out far enough to get the drill in and get my stuff done.

I measured the hole first to insure I wasn't going to drill too deep. The hole was 3/4" deep so I taped off the drill bit to insure I didn't go too far.

First step was to drill out the hole. The Big-sert is setup to replace a bad helicoil and made the hole slightly bigger.

Then they have a countersink cutter, You use this to create a small indentation to accept the top of the insert which doesn't go the whole length of the hole.

I used an air blower I use for my computer to blow out the hole when necessary.

Next step was to use the thread cutter and cut the threads. I only went a couple threads deep before I backed it out, cleaned off the tool and blew out the hole. Then by hand screwed it back in and cut a few more threads, backed it out etc... I used some WD40 as my cutting "Lubricant" and it worked ok.

The last step you screw the insert onto the applicator and slowly screw it into the hole. Once it goes all the way in you keep screwing the tool down a little further. The end of the insert has a pin that binds against the side to insure it doesn't back out. I also applied some locktite blue. I thought I grabbed red but blue should work better than nothing. Once I bottomed out the insertion tool I slowly backed it back out.

I blew out the hole again to insure no shavings were still in the hole and installed my "adapter". It bolted right down and held well so hopefully it will seal up.

Biggest issue I am having now is trying to get the bracket to lineup for all of the bolts. Got dark so put it away for now... Will get back to it tomorrow. I think when I wedged the bracket away from the engine I also pushed it down. I was able to get 3 of the 4 bolts into place but still working on the fourth. What a pain in the butt. If I could get the pully off the power steering pump it might make things easier but haven't had much luck with it. After removing the upper and lower shroud and the fan I was able to get to the bottom bolt.

I did buy a pulley puller but the pulley did NOT come off. Luckily I didn't need to pull it off at this point. I suspect if I ever need to replace my power steering pump I may have to try something different but for now not going to worry about it.

Was thinking about trying to pressurize the coolant system before I get everything back together to insure this fixed the leak but not sure how to do so. I do have a compressor but guessing I would have to get some sort of fitting for it or something.

Rodney

 
  If you do not have all new antifreeze in yet and still have any of your old hoses.
You could take barbed garden hose end in one and use your garden hose to pressure the system.  
They do have the screw on end repair kits in 5/8 and 3/4. Just do not know your water city or well.
May need to neutralize.
With all the sensors and added things that are on vehicles would this work?  

 
Actually do have most of the old hoses and I looked online. people have done different things to pressure test their systems. I still have about 15 gallons of high purity water I picked up for flushing out and refilling my coolant system last year. I have seen videos where people have modified coolant lines with a T and have also modified their caps.

May try something with that stuff... I do need to readjust my steam lines and try to get the bracket back on.

If I had been able to pull the power steering pulley I would be able to get this stupid bracket back on much easier. I suspect I bent a hard line slightly when I moved the bracket out without removing the power steering pump. I MAY go ahead and remove the power steering lines and drain out the fluid. That should allow me to move the bracket much easier and the fluid hasn't been changed since I owned it anyhow. (About 80-90k miles and 7 years)

Becoming much more of a pain in the butt that I figured it would be..

Getting the coolant line the right length is harder than I would have imagined too... My first attempt was too long so I kept shortening it until I made it too short... So I used some of the spare tubing and made a new one... Slightly longer than the old one... Of course too long... So going to try cutting 1/8 inch off and trying again.  Did I mention what a pain? I have probably about 20 hours into this project... And still not done...

If I would have been able to just replace the piping I had it would have been maybe a half hour job.. But then again the helicoil failing was the bigger issue.
 
What year and engine do you have?

If you have a pre 2008 5.3 check the heads on the passenger side. You should find a 3 digit number either 706 or 862 if I remember correctly. The 706 heads are prone to cracking.

I had numerous issues.. Water pump was leaking, replaced and was still loosing coolant. pulled valve covers and noticed BOTH heads had caramel color in them and standing coolant in them. Replaced heads and still was loosing coolant. Ended up being a bad helicoil on the driver side "steam vent" connection. The Tubing was also very corroded and could have had a pin hole in it the whole time so I tried to replace it but other than used ones did not find a good replacement.

Ended up going after market. I would NOT go Trickflow. Was not cheap and was not engineered well.

I would check for any sign of coolant loss. If you have to you may end up power washing your engine compartment to look for it. be careful not to directly spray electrical connections but otherwise should be safe. Then look for goey areas. On my truck the top of the engine was black and goey 2,000 miles after the head swap. The mechanic that worked on my engine had power washed the whole engine top and bottom before he worked on it so it was obvious where it was leaking...

But again if you suspect your heads because of them being the 706 heads I have a thread on my journey on those too... So far truck runs almost as well as my gf's 2013 silverado which has about 240,000 less miles...

Rodney
 
03 5.3. Basically I suspect heads are cracked, but hold out hope it's something simpler. I lose coolant at a rate of about a gallon every week and a half to two weeks. Nothing showing in the oil or anything, so just trying to track it down.
 
If you don't have wet carpet and no puddles under the truck pull both of the valve covers and check. Was a pain to pull the passengers side because I couldn't get to one of the bolts on the coil mount.

As I mentioned check my thread about the head cracks I had. if you fix it now you can save the engine if it is cracked heads. I got a good deal on some rebuilt heads and no complaints other than the bad helicoil. And if you have that issue I can sell you the remainder of my big-sert repair kit for cheap...

If your loosing that much coolant it is well worth the 2 hours of time to pull the valve covers.

Here is the thread on my ordeal...

http://www.chevyavalanchefanclub.com/cafcna/index.php/topic,150622.0.html

I never did really see it in my oil but certainly was there...


 
Will do!  Thanks for the info, I may ask more later! Got it at a buddy's shop with lots of tools, so we shall see!
 
My engine has almost 270k miles and runs great with the "new" heads. The mechanic warned me it could force the bottom end to wear out faster but lets be real... If I get 300,000 miles out of this engine I am thinking the $1300 I got into the heads were worth it...

Gets me to when I can upgrade to a bigger engine with SC... ;)


Rodney
 
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