Jeep Cherokee / Liberty 2004 3.7 Crank but no Start

[Chris French]

Way to go Chris on this success story.
It was great to follow along and see that you succeeded.
The last question I have is how and the heck did the tappets fall off and case this mess.
How did you prevent them from ever falling off again.

An excellent question! I can only speculate but I'll have a go.

There were 3 things I think were contributing
1. The lifters were gummed up, so the retaining spring was not doing its job when the engine was switched off
2. There was water in the oil from HGF and there was even creamy oil inside the lifters
3. I am speculating by both the lack of water in the engine and a faulty thermostat that the engine was over heated on its last journey, boiling any water in the oil

So could be an overheat causing boiling water in the lifters giving them and extra reason to collapse when the engine cooled down. So when it was started with several loose rockers, they were thrown.

Interesting that all 3 rockers were exhaust side. Also interesting that 3 rockers were thrown at the same time and it did no permanent damage.

In terms of prevention, I have renewed all the lifters, fixed the HG and replaced thermostat and oil. Time will tell I suppose whether it is a permeant fix, but the top end of the engine sound very quiet at the moment.

Thanks again for your support.