Compression

[Crisjr14]

Ok so I bought a compression tester to check my '53 and front front to back front being # 1 and last one being # 6 so 1 thru 4 all reading at around 120 5 & 6 I get no reading but when I put a rag in each and turn car over they both shoot out like rockets so any advice as to what is going on or what I need to do please and thank you 

[Los_Control]

Ghost

[Crisjr14]

Los Control???? 

[Los_Control]

No way to explain it .... you must have ghost.

 

Obvious you must have compression in those 2 rear cylinders if the compression is blowing the rag out of the spark plug hole.

Seems your new gauge is working correctly if it measures the first 4 cylinders.

 

If by chance you had a blown head gasket between 5 & 6 it is possible that when you install the gauge on one of the cylinders, it all escapes out of the adjoining cylinder.

Usually it would just show a low reading though ...... Unless the head gasket is so blown it has a Interstate opened up to allow free passage of compression.

 

So put a plug in one hole while you check the other and see if you get a reading. Then swap plug and gauge to check other .... If you get a low reading from them both at this time .... at bare minimum you have a blown head gasket ..... you will need to pull head and investigate further.

[Crisjr14]

Ok thank you going to try that now will give update later

[Hickory]

I would go with a blown head gasket, the gauge says your not making pressure, you remove the restriction aka gauge and you will still move air. Pressurize a cylinder at tdc firing and listen for air in the adjoining cylinder.

[Hickory]

If you don't own a leak down tester you could use a rubber tipped blow gun