Coolant leak,
Thread Starter
Staging Lane
Joined: Aug 2013
Posts: 63
Likes: 2
Coolant leak, Hi guys,
I have a 1985 S10 pickup with a 2003 5.3 I got from a Suburban. It wasn't running for three years because of the build. It runs good but after I drive it awhile and return there is a coolant leak at both cylinder heads at a few head bolts about a teaspoon amount. I added a few of those GM tablets, the ones Cadillac used for the Northstar engines for the their head gasket problems. I drove about my truck about 200 miles and no visible leaks and no coolant lose. My question is should I replace the head gaskets and maybe have the heads checked or just let it go and watch for leaks. I also worry if I remove the heads what is the chance of breaking a head bolt in the block and really be screwed. The 5.3 has a cast iron block and aluminum heads. Should I use metal head gaskets and ARP head bolts (reusable bolts) if I go that route. Any suggestions or help would be apreciated. Thank you.
I have a 1985 S10 pickup with a 2003 5.3 I got from a Suburban. It wasn't running for three years because of the build. It runs good but after I drive it awhile and return there is a coolant leak at both cylinder heads at a few head bolts about a teaspoon amount. I added a few of those GM tablets, the ones Cadillac used for the Northstar engines for the their head gasket problems. I drove about my truck about 200 miles and no visible leaks and no coolant lose. My question is should I replace the head gaskets and maybe have the heads checked or just let it go and watch for leaks. I also worry if I remove the heads what is the chance of breaking a head bolt in the block and really be screwed. The 5.3 has a cast iron block and aluminum heads. Should I use metal head gaskets and ARP head bolts (reusable bolts) if I go that route. Any suggestions or help would be apreciated. Thank you.
The tablets are designed to seal minor imperfections in the cooling system. GM drops one in every new vehicle in the assembly plant, not just NorthStars. I put one in every build I do here at the shop, if it gets a water pump on it. If not, I tell the client to drop one in the radiator before adding coolant. Your fine here with your truck.
I’d run it until the problem arises again, and if it never does, then good on you sir. However…it’s a 2003, which I believe was in the Castech years for crack-prone head castings. So there’s a good chance that the heads are cracked anyway. If it were mine, I’d run it until the leaks re-develop and then I’d pull the heads and see what’s going on. Until then, enjoy that little hot-rod.
TECH Senior Member
Joined: Jun 2016
Posts: 22,308
Likes: 3,625
From: Central Cal.
"No thank you please, it only makes me sneeze, and then it makes it hard to find the door....."
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?
Pouria Savadkouei
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
When I built my Darton sleeved LS1, a company some may remember, Wheel to Wheel, used a pack of them, what I called GM "seal tabs," in my block, which was very slightly seeping coolant. Kurt Urban ran W2W then. He said he didn't care who sleeved the blocks, they all seeped a bit without the tabs. Mine stopped after adding them. If it were me, I'd make a few strip passes after adding them to your coolant, and if it's still not losing any, run it until it's junk. My opinion.....