No compression

Hi I just put a new engine in my mp5. Tried to start up didn’t start. I checked the compression. It said 5,5,35,20 psi in the cylinders. I’m working on taking off the head and seeing what’s going on. But before I continue can it being out of time cause such low compression?
 

pcb

The Diagram Dude
:
2002 MP5
But before I continue can it being out of time cause such low compression?
Yes!

Your valve timing is probably off.
Check that first...

If your valves are open during the compression stroke, you will have no compression...
 

pcb

The Diagram Dude
:
2002 MP5
The two small notches have to face each other correct? And if that is correct if the crank was off would it cause 0 compression?

Yes it could.

Check and look for this...


Screenshot_20220106-170721_Acrobat for Samsung.jpg




Thread 'Protege Timing Belt Change (How-To)' Guide - Protege Timing Belt Change (How-To)
 

pcb

The Diagram Dude
:
2002 MP5
Ok thank you. And that could cause the compression to be at zero? People were telling me no times can’t cause compression to fall that low.


If your intake valves happen to be open for most of the compression stroke, then you could definitely have no compression.

A quick look at your timing will show you.

Being off by a single tooth on the T-belt is enough to have the engine not run.
 
If your intake valves happen to be open for most of the compression stroke, then you could definitely have no compression.

A quick look at your timing will show you.

Being off by a single tooth on the T-belt is enough to have the engine not run.
Ok thank you so much I’ll take a look before I keep going.
 
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pcb

The Diagram Dude
:
2002 MP5
Check your toothed ring while your in there...

They are glued to the crankshaft and can break free and slip or even fall off...
EDIT: They are glued to the crank pully.

It should look like this...


Screenshot_20220106-172349_DuckDuckGo.jpg



The keyway notch should be allinged properly with the missing tooth on the timing ring...
 
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I had the same issue and got my head machined and just a couple minutes ago I finished everything and tried to turn it on but it didn’t, so I went ahead and tested for compression and mine got roughly 75-100 psi in all cylinders and I was looking through the manual to see which is the range it should be at but couldn’t find anything, do someone know what it should be?
 
I swapped back to my old head and it’s running and driving with problems here and there. I’m very excited/stressed lol. Is there anybody who knows a Machanic for protégés in central Florida?
 

pcb

The Diagram Dude
:
2002 MP5
I swapped back to my old head and it’s running and driving with problems here and there. I’m very excited/stressed lol. Is there anybody who knows a Machanic for protégés in central Florida?

Did you reuse your head gasket and head bolts when you swapped the head?
 

pcb

The Diagram Dude
:
2002 MP5
Do you have any codes?

Your used engine probably had a warped head.
A lot of our P5's ended up at the wrecker after the engine overheated.
 
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