Engine issues

H

hayjoesam

Member

Posts

11

• Saturday at 17:27

• #1

Hello, I've been trying to get my 2.25 petrol engine running sweet. However when using a strobe to check the timing, it will only run when advanced past the timing marks. Ive fitted an electronic ignition and a new distributor as well as a new coil. I put the advanced timing down to better fuel and the refreshed ignition system.

I put the compression tester on just for peace of mind.

Cylinder 1 50 psi
Cylinder 2 50 psi
Cylinder 3 50 psi
Cylinder 4 0 psi.

So with all the above information where to start.

 

tottot

Well-Known Member

Posts

8,632

Location

west wales coast

• Saturday at 18:24

• #2

A psi of 50 on first stroke is not great and zero is well bad. How did you conduct the test. Run us through how you did it.

 

H

hayjoesam

Member

Posts

11

• Saturday at 20:29

• #3

All sp

tottot said:

A psi of 50 on first stroke is not great and zero is well bad. How did you conduct the test. Run us through how you did it.

Click to expand...

All spark plugs removed, compression tester screwed into spark plug hole. No choke and wide open throttle.

 

L

lynall

Well-Known Member

Full Member

Posts

27,261

Location

Kent

• Saturday at 20:44

• #4

I would say someone has stolen your piston rings.

 

tottot

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Posts

8,632

Location

west wales coast

• Saturday at 21:23

• #5

Turned over with starter? And did you not get any improvement after 3/4 strokes?
As lynal above and/or valve seals gone walkabout.

 

H

hayjoesam

Member

Posts

11

• Today at 09:41

• #6

 

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H

hayjoesam

Member

Posts

11

• Today at 10:43

• #7

tottot said:

Turned over with starter? And did you not get any improvement after 3/4 strokes?
As lynal above and/or valve seals gone walkabout.

Click to expand...

I have found a cracked intake valve on cylinder 4, and possibly a cracked valve seat.

 

steve2286w

Well-Known Member

Posts

5,215

Location

monkeyangerland

• Today at 11:01

• #8

Book values are 145psi for 7:1 and 160 psi for 8:1 head, 50 seems well low but it’s consistent in 3 anyway I would guess your tester not reading correct too.
If you have a cracked valve seat , these can be replaced to suit unleaded petrol

 

H

hayjoesam

Member

Posts

11

• Today at 12:41

• #9

.

 

H

hayjoesam

Member

Posts

11

• Today at 12:42

• #10

Whats

steve2286w said:

Book values are 145psi for 7:1 and 160 psi for 8:1 head, 50 seems well low but it’s consistent in 3 anyway I would guess your tester not reading correct too.
If you have a cracked valve seat , these can be replaced to suit unleaded petrol

Click to expand...

what is the best way to tell if its the higher compression head? I can't make out if there is a 8 on the head. The push rods measure 182mm

 

tottot

Well-Known Member

Posts

8,632

Location

west wales coast

• Today at 13:21

• #11

The compression number is on the head NS near the rocker box in the middle.