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View Full Version : SR20det Redtop no compression in 3 cylinders


hdhype
10-25-2012, 04:53 AM
I recently put in a redtop into my s13. I got it started and running this past weekend for the first time. I was having an issue were once I hit positive boost pressure (around 2000 RPM) my engine would lose power much like if I had taken my foot off the gas pedal.

Today I go to crank up my engine so I could troubleshoot some more. It started rough, going back and forth between 800 - 1500 RPM. Then it just stops. I tried cranking it to no avail. I decided to check compression, and only cylinder 2 was able to show anything at all (8 Bar). Cylinders 1,3,4 don't show a thing.

When I look down the spark plug holes I can see each cylinder move when cranked. Another thing I remember noticing is that when it cranked up, every once-in-a-while I would hear something that kinda sounds like grinding for 1/6th of a second then go away.

Edit*
Another thing I want to add is that it was idling just fine yesterday. Also My oil light kept flickering on and off even though I have plenty of oil in it.

Sileighty_85
10-25-2012, 05:03 AM
Wiring/ MAFS issues for the running/driving issues
or Fouled out plugs

Compression: bad gauge/ incorrect testing procedure

Get an Oil pressure tester to make sure your oil pump is not failing

hdhype
10-25-2012, 05:18 AM
First I want to say thanks for the quick reply Sileighty_85, looking at your build threads have been an inspiration.

For the compression test we used 2 gauges (and 2 different people testing) just to make sure it was reading correctly. I even felt air coming out of cyl 2 when I put my hand above it. But I felt nothing coming from the others.

Will do with the oil Pressure tester.

fliprayzin240sx
10-25-2012, 08:31 AM
Take the valve cover off, look in the FSM and double check to make sure your mechanical timing is good. It sounds like its off, hard to show 3 dead 0 compression cylinders on one sitting. I'm willing to bet that its off and the valves arent closing properly

hdhype
10-25-2012, 11:19 AM
I checked under the valve cover, and I have good news and bad news.

Good news is that it was easily identifiable that the timing was off...

The bad news is that it was easily identifiable that the timing.. was off

http://i.imgur.com/sWQpS.jpg
http://i.imgur.com/KCNlF.jpg
http://i.imgur.com/Gxu74.jpg
http://i.imgur.com/2P6Gk.jpg

Now I would imagine that since these are interference engines....

I appreciate Sleighty_85 and fliprayzin240sx for helping me out.

I'm going to go re-evaluate my life.

future
10-25-2012, 11:26 AM
Damn. Well at least you didn't have to go to into depth. Good luck on the rebuild

Davidna2fi
10-30-2012, 11:30 AM
$10 says you used an impact on that bolt....

Did you use an impact to put the camshaft bolt on? If so that's probably why it broke like it did since it had cracks already in it and just over time the tension cracked it even more until it broke off.