2.5t timing belt broken need help with leakdown test

[RickHaleParker]

How do you do a compression test if the intake valve won't open to let air in?

Move the piston to the bottom before installing the gauge. That will fill the cylinder with air.

[atikovi]

Maybe I should have worded my post differently. Instead of ASKING how you can do a compression test with the valves disabled, I should have replied to the poster that you CAN'T do a compression test with the valves disabled, but pointing out someone's error like that seems rude.

[cn90]

For those who are short of budget, go to junk yard to get a water pump and TB for cheap.
Install them (don't even need antifreeze, just add distilled water for now).
Do a compression test and go from there.

PS: I wonder what brand of WP or TB that failed at 50K (the O.P. said the WP and TB were replaced 50K prior to the event).
Most local repair shops use parts from Autozone, Advance Auto etc. and you can guarantee that they use Chinese WP etc.

[RickHaleParker]

Jeepers! Guess some people will miss the dead obvious even after a spell out.
All the valves must be closed to do a compression.

[atikovi]

HAHA. Not sure if you’re deliberately being obtuse or just don’t understand the point. A compression test requires numerous revolutions of the crank and numerous compression events in the cylinder to get an accurate result. Why do you think the gauge needle keeps bumping up 5 or 6 times as you crank? If the valves were always closed, the piston would just bounce up and down compressing and expanding the same amount of air resulting in an inaccurate reading.

[MoVolvos]

Pulling the upper cam cover would close all the valves as the pressure holding them down is relieved. But a compression test would not work and could not be performed in this state. Only a leak down test as the cams are not moving.

I assume you already know this.

Hi atikovi,

SuperHerman qualified what it took to do a compression test if you can't turn the engine because of the potential of having stuck or bent valves.

EDIT: Not a real compression test in the since but at least whether the cylinder can hold pressure.

[cn90]

O.P.

I have the following set with only 90K miles on them, if you want, you can have them for the cost of shipping. These are factory items, still have a long way to go as they only have 90K miles:
- TB
- WP
- 2 TB pulleys


This way you can use them for the purposes of compression testing.

[jonesg]

I would pull the head and take it to an auto machinist shop . They will tell you what it needs.
I've seen numbers around $600.