What ft pounds are you torquing the head bolts too? I think I read that you are re-using your bolts.

I always swap to arp studs / nuts which allow 60 ft pounds of torque. I wonder whether that would impact your leak results?

I torqued to 61 ft lbs.

more testing, nothing changed, but did not seem to have the same change in color. I have attached a pic from the latest video, comparing the colors before (bottom) and after test(top)

Not very good with paint, here is the video

 

Edited June 27, 20195 yr by Dave WM

final run, come and get it Jeff!

 

 

So it seems that whatever was going on that made the chemical change color has been fixed, right?

Did you find a smoking gun as to what was going on? Did you do anything other than replace the head gasket?

  On 6/29/2019 at 1:56 AM, Captain Obvious said:

So it seems that whatever was going on that made the chemical change color has been fixed, right?

Did you find a smoking gun as to what was going on? Did you do anything other than replace the head gasket?

color change seems to be fixed, I did nothing between when it was changing to now. Never found a smoking gun.

orig check out of the engine before any work showed color change repeatable.

replaced HG used orig N42 head (the one on the bench), still color changed repeatable. The orig HG looked fine, it looked OE, used a felpro. I did what I consider a good job of cleaning the block deck and the head before reinstalling with the new gasket. No smoking gun.

replaced HG AND head (to the MN47) still color changed on several tries days apart, then tried some more after a few more days, no more color change, repeatable.

It bothers me since I have no event between color change and no color change, hence my gift horse comment in the video. I would of course much preferred something I could attribute the no color change to directly.

Perhaps it would be prudent to try it a few more times before I tear down the setup, just to confirm the no color change. This video is pretty short but the stat was def open and in the previous no color change test runs the engine had been running for at least 20 min maybe longer (fully warmed up).

 

 

 

Edited June 29, 20195 yr by Dave WM

Ok one thing I forgot, I did have some exhaust manifold leakage, and some valve cover gasket leakage (oil dripping on manifold). I tightened up the exhaust manifold stud nuts and replaced the valve cover with a new OE gasket. Zero leaks from either of those now. I failed to mention as I could not see how that could effect a gas in coolant test. It did happen between the bad and good results, So it was an event, just something I don't see as a cause of the effect.

I Like the video.  Mine starts like that after it's warmed up, but when it's cold it takes a few more revolutions and stumbles for about 2 seconds until it evens out to cold idle.  It's good to see a benchmark for normal cold start.