Head leak down

[202mphbusa]

#1 less than 1%
#2 about 4%. Exhaust port leak
#3 less than 1%
#4. About 2%. Exhaust port

 

[4g63rc]

#1 less than 1%
#2 about 4%. Exhaust port leak
#3 less than 1%
#4. About 2%. Exhaust port
View attachment 1670190

Looks like a pretty tight motor to me. Did you do a compression test. ? I compare both, numbers. I had recently did a leak down test on mine and was 1% on 1 -2 & 3 and 3% on 4. Was 145 psi on 1-2-3 and 142 on 4.

 

[202mphbusa]

Looks like a pretty tight motor to me. Did you do a compression test. ? I compare both, numbers. I had recently did a leak down test on mine and was 1% on 1 -2 & 3 and 3% on 4. Was 145 psi on 1-2-3 and 142 on 4.

not a huge believer in compression test
leak down was much higher on assembled motor
Thinking it pushed the head gasket between 2-3
and a coolant jacket as she was overheating

 

[4g63rc]

But was it pushing coolant?

 

[202mphbusa]

But was it pushing coolant?

It pushed into the overflow
was running rough and temp was overheating

 

[jellyrug]

History of the motor? Root cause for valve leaks, overheating and head gasket going poof?

 

[greg3852]

History of the motor? Root cause for valve leaks, overheating and head gasket going poof?

He likes to push the limits.

 

[202mphbusa]

Had a O2 sensor go bad at Loring
overnighted one,,,,,BUT I had made changes based off the failing unit
First run the next day I made a run when I should have double checked the changes, instead I wrongly figured it would be okay on low boost
40 seconds WOT at 5PSI she gave up the ghost

Motor had been together sine the HUGE meltdown at Loring in 2017
probably 20 Landspeed runs
100 trips to Mexico