A couple cylinders fire, then nothing...
Thread Starter
On The Tree
Joined: May 2005
Posts: 189
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From: Utah
A couple cylinders fire, then nothing... I got my car correctly setup now, with the correct valve lash so the valves aren't hanging open now. Once my buddy and I got that done, we hooked everything back up and tried to fire the engine. It sounded like it fired on a couple of cylinders, and then nothing but the sound of cylinder compression, but no firing of the cylinders. We did notice that gas had leaked out of the passenger side header and made a small pool under the car. We tried it again just after the first time, but nothing tried to fire this time. We worked on his car for maybe 20-30 minutes, and then went back to mine and tried to start it again, and again a couple cylinders fired right off the bat, but then nothing again but the rotation of the engine and compression sounds. We checked spark from a few of the spark plug wires, and it's sparking without a problem on the ones we checked.
Any ideas on what could be the problem? Could the timing be off that much that it wouldn't even start the engine, or am I missing spark on most of the cylinders, like the spark plugs are bad?
Any ideas on what could be the problem? Could the timing be off that much that it wouldn't even start the engine, or am I missing spark on most of the cylinders, like the spark plugs are bad?
TECH Enthusiast
Joined: Jul 2003
Posts: 697
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From: Evansville, IN
If it is putting that much gas in and is not firing, I would be careful. You can wash out the cylinder walls and you wont get ring seal. This will cause low compression. Are you getting good spark on all the plugs? Are you sure you have the firing order correct with the wires? Are you sure the opti is timed correctly?
Thread Starter
On The Tree
Joined: May 2005
Posts: 189
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From: Utah
I'm not sure about the opti timing, as I wasn't the person who setup the timing chain. I had a shop work over the block to make sure everything was alright, and then put the bottom end back together. I'd assume they'd at least think to set that correctly, but i'll double check with them. The wires were hooked up exactly as the haynes manual shows a stock opti should be. I'll double check those wires, as well as replace all the spark plugs with new ones. I'm just hoping I don't have to tear off the front again and replace the opti, or worse, do the timing chain stuff.
Thread Starter
On The Tree
Joined: May 2005
Posts: 189
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From: Utah
Just a quick question about valve lash, when doing the valve lash to a certain measurement, say like .022, should there be play between the roller tip of the rocker and the top of the valve? I tried that, but the play between the roller tip and the end of the valve stem just didn't sit right with me, I felt it needed to be tight. Is this correct, or should I go back through and put them to that clearance and let them be a little bit sloppy like it feels?
Originally Posted by Azthrei
We did notice that gas had leaked out of the passenger side header and made a small pool under the car.
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On The Tree
Joined: May 2005
Posts: 189
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From: Utah
I don't have something for reading the codes, and many are going to come up because i've got lots of things removed. The custom oil pan didn't allow for the oil level sensor, no AIR, EGR, or CATs, but i've had those programmed out. No EVAP as well, pretty much nothing for emissions stuff. I'll be double checking the wires tonight and make sure they're all connected up properly and tightly. If that doesn't let it fire up, i'll go buy some new spark plugs, i'm using TR6's right now, but I think i'll be fine with some TR55's. I think I might redo the valve lash as well, with the feeler gauges I have, although I don't like the feeling of the rocker sitting loose when I use those feeler gauges on it.
Thread Starter
On The Tree
Joined: May 2005
Posts: 189
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From: Utah
I am running a solid roller cam, so going anything tighter then zero lash will leave the valves hangin open. I had my buddy pretty much do zero lash while I was turning the rotating assembly, but i'm not sure he got them right, and might have tightened them too tight. I really think I should do them over then.
Then I retract my statement. Regardless though, I messed up the valves on mine after cam install (yeah I did the whole install and couldn't setup the valves, lol). It still ran, very sloppily, you could hear the rockers banging around, but ran nonetheless. I don't know if I would pin the valves even though it would be a good idea to check (for later).
Thread Starter
On The Tree
Joined: May 2005
Posts: 189
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From: Utah
So it's down to this, should I try and set the rockers to zero lash with a solid roller cam? Or should I use the feeler gauges to set them to a different lash, but then possibly run into issues with them being kinda sloppy from that gap?
Thread Starter
On The Tree
Joined: May 2005
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From: Utah
Ya, just trying to rotate the engine while there is compression was a bitch while I was under the car. The only problem is I only trust myself to adjust the rockers, but my buddy wasn't strong enough to rotate it under there with the compression makin it hard as hell.
Originally Posted by Azthrei
Ya, just trying to rotate the engine while there is compression was a bitch while I was under the car. The only problem is I only trust myself to adjust the rockers, but my buddy wasn't strong enough to rotate it under there with the compression makin it hard as hell.
Thread Starter
On The Tree
Joined: May 2005
Posts: 189
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From: Utah
Using the starter to do it wouldn't be accurate enough to stop it in the right spots, but pullin the plugs would be a good idea, then I could replace the plugs so I know for sure i've got some new good plugs in there.