Smoke After Head Gasket Replacement - 01 WJ
 

So radiator blew and the engine got a little warm causing my passenger side head gasket blew out and puked coolant down the block. Ended up changing both head gaskets, timing chains, thermostat, radiator, and water pump.

The guys at AutoZone think it is blow by from cleaning the mating surfaces with brake clean - which was my mechanic buddy's go to choice. Uses it every time he said. AutoZone thinks it is the cylinder walls being dry and one of the staff said it will self lubricate and the other said to drop a half ounce to an ounce of oil in the cylinder, run it for a while, then replace the spark plugs.

My temp sensor in the top of the block is broken - just got a new one. Only have had it started for about 5-10 minutes total (3 minutes intervals or so) since reassembling it. Oil is not milky and reads in the regular range. Coolant levels normal, seems to not be boiling like it was before when the coolant system couldn't be bled.

Anyone run into an issue like this? Let me know if you need further clarification.

After you change Head Gasket and removed Cylinder Head etc oil, coolant, etc will drip onto manifolds, rear bell housing and probably drip onto exhaust. When I put everything back together my XJ probably smoked for about 10-15 min. If you only did it in 3 min intervals, maybe you didn't let it get hot enough to burn off all the oil etc. If everything reads fine, coolant seems to be flowing etc let it run.

My dad had the same experience when swapping out one. He said the smoke went away after 20 minutes and just things it was any oil going down the exhaust.

Okay, I will put my new temp sensor in and hopefully that will clear my CEL and I will just let it run for a while.

Thank you both!

Put the new temp sensor in and started it up. about 2 minutes in it started to smoke a little and the temp gauge was at 25%. At about 5 minutes there was the same amount of smoke as the video above and gauge was at 50%. Around the 7 minute mark it shut it off because I was at the 75% on the gauge. I suspect it is because I didn't bleed the coolant system so I tossed it on jack stands while it cools down and I'll bleed it and my power steering tomorrow.

Any other suggestions are welcome!

Usually bleeding is not really really needed to get going. How did you refill it after the part replacements? Did you make sure block was nice and clean for the head gasket? Did you torque bolts down correctly?

Sometimes exhaust gaskets take a little heat to seal fully.

So, this is an 01, right?

I'm an idiot. I just saw this was for a V8 lol.

I poured it into the radiator, squeezed the upper rad tube to get some of the bubbles out then poured some more into the overflow. Ran it for a few minutes and the overflow was empty so I added more, repeated until it was at low when warmer. It cooled off and is at full.

I had cleaned the block with brake cleaner and used a snap on scraper my buddy had shown me how to use to clean the block, the heads were resurfaced professionally.

The head bolts were torqued down by my friend who is a mechanic. He had talked about torque specs so I can only assume they are to spec.

So I should run it up to temp another go or what does that mean for the overheating issue?

Correct, this is a 2001 Jeep Grand Cherokee with the 4.7 V8. 165k miles.

I don't get it. Are you saying you think there is a problem because after 7 mins of idling the temp gauge on the dash shows you are too hot? What temp does that mean? Have you read it with a scan tool to see what the cts is reading? If it is too hot, have you slapped the radiator pressure gauge on it to see if there is a leak, such as in the head or gasket?

When you took the head off did you have it checked by a machine shop to see if its straight or not cracked ?

He said they were resurfaced professionally. Not sure what else they would have done or checked

The temp that went high was the coolant temp. I plan on bleeding it and running the hot air to try and get the bubbles out, those are hopefully causing the sensor to read high. I have not read it on a scan tool unfortunately, I will see if that is needed after I bleed it tomorrow. Same with the pressure test. Thanks!!

The shop did not specifically MagnaFlux test it or anything, but my friend works at a shop and they have inspected every head they have brought to them prior to doing anything any work to make sure they aren't spending their time on a lost cause. Thank you both!

So I have been working on this with the end goal of selling it and a friend just offered to trade a Lincoln 185 TIG and a Double Star AR-15 with a scope, mags, collapsable stock etc.. Thoughts?