PDA

View Full Version : trouble shoot sr20det no compression


porkfriedrice
12-16-2010, 10:42 PM
red top s13 with no compression. head gasket was blown but car ran before. 1 cam broke after removing head other had stress fractures so got new cams from a black top s13 (i was told) and new steel headgasket. head was taken to shop and is straight and block was straight edged, head torqued to spec. now it has 0 compression on all 4 cyl. could it be the cams? what difference is there with blacktop cams? need help thanks.

nismoman
12-17-2010, 08:37 AM
hmm weird, is the timing chain on correctly allowing the valves to close completely?

Sileighty_85
12-17-2010, 03:29 PM
Mechanical timing is probably set incorrectly,

codyace
12-17-2010, 05:33 PM
Check your valvetrain. If you broke a cam you could have damaged a valve, which would lead to 0 compression.

Also check mechanical timign as described above.


0 Compression is obviously a huge air leak. Even a bad headgasket will show some compression.

porkfriedrice
12-18-2010, 02:11 PM
double checked timing chain is correct. Head was checked by machine shop and cams did not break until they were removed so no valves are messed up. it is all 4 cyl that have no compression.

codyace
12-18-2010, 07:24 PM
Again, to have zero (and pure zero) compression in a cylinder you need something drastically wrong with the engine.

Valve train
Valves

I can't see a 'fresh' block and 'new' headgasket ever giving zero. Heck even on motors that have known bad HG's, they are simply low...not ever zero.

eklips3
12-18-2010, 10:08 PM
try another compression tester.

i would say mechanical timing as well though

nismoman
12-19-2010, 09:00 AM
Can you feel or hear air rushing out of the plug holes when you turn it over?

japslapsilvia
12-20-2010, 09:08 AM
just do a leak down test to determine where n why you have zero compression.