THe NAC Lots-O-BFG KO2 Thread

Re: THe NAC Lots-O-Post Thread aka North America Home Owners Association Thread

Just pulled the heads off the j10. Did the light and water test for a suspected bad valve seat. And they test out fine.

I swapped out plugs and coils, swapped injectors, and did everything I could before tearing into the engine.

Put air in the cylinder at tdc and it whistled out the exhaust.

Unless these is some stupid honkin' issue with these that makes cylinder 3 misfire like a bastid and a handful of other cylinders have a dozen random misfires every minute or so when under a load Idk what to do. I can't imagine valve timing is off as it is impossible to screw it up on these, and it idles and runs just fine until you really put a load on it.

Gonna give them a valve job anyway while they are out, but it is really discouraging when you don't know if its surely the issue while its all apart.
 
Re: THe NAC Lots-O-Post Thread aka North America Home Owners Association Thread

Is it actually impossible to screw up the valve timing? Did you check to see if it leaks just before/after TDC? Try the free things first.

You are one patient sumbit.
 
Re: THe NAC Lots-O-Post Thread aka North America Home Owners Association Thread

Whateva. It's chopped up now anyway. And just do racecar gauges.

I don't wanna!!! I wanna keep the stock dash in there for some odd reason.
 
THe NAC Lots-O-Post Thread aka North America Home Owners Association Thread

Just pulled the heads off the j10. Did the light and water test for a suspected bad valve seat. And they test out fine.

I swapped out plugs and coils, swapped injectors, and did everything I could before tearing into the engine.

Put air in the cylinder at tdc and it whistled out the exhaust.

Unless these is some stupid honkin' issue with these that makes cylinder 3 misfire like a bastid and a handful of other cylinders have a dozen random misfires every minute or so when under a load Idk what to do. I can't imagine valve timing is off as it is impossible to screw it up on these, and it idles and runs just fine until you really put a load on it.

Gonna give them a valve job anyway while they are out, but it is really discouraging when you don't know if its surely the issue while its all apart.


You should put the 305 back in
 
Re: THe NAC Lots-O-Post Thread aka North America Home Owners Association Thread

Just pulled the heads off the j10. Did the light and water test for a suspected bad valve seat. And they test out fine.

I swapped out plugs and coils, swapped injectors, and did everything I could before tearing into the engine.

Put air in the cylinder at tdc and it whistled out the exhaust.

Unless these is some stupid honkin' issue with these that makes cylinder 3 misfire like a bastid and a handful of other cylinders have a dozen random misfires every minute or so when under a load Idk what to do. I can't imagine valve timing is off as it is impossible to screw it up on these, and it idles and runs just fine until you really put a load on it.

Gonna give them a valve job anyway while they are out, but it is really discouraging when you don't know if its surely the issue while its all apart.

Know anyone with a real scan tool to see what all the sensor outputs are when this happens? Assuming you've checked fuel pressure? Was it idling high? The plastic intake gaskets are known to crack and cause vac leaks. A bad valve or seat would be noticeable anytime, not just under load. Are you sure you were on tdc #3 during compression and not exhaust? Only way to verify is to make sure both valves are closed or back off the rockers
 
Re: THe NAC Lots-O-Post Thread aka North America Home Owners Association Thread

If the valve timing was off, everything on the motor would be off. Not just one or a few, occasionally.

When I was testing the heads on the SHO motor I had a few with some slight leakdown; I just knocked on the top of the valve a few times and the leaks went away. It was because of carbon buildup not letting the valve seat nicely (which will also affect valve lash etc).

I pulled the heads and dropped all 24 valves, cleaned and lapped each one, and have 5% or less leakdown on all cylinders now. That alone brought every valve back into proper adjustment without actually having to adjust anything. Wasn't difficult, just time consuming.
 
Re: THe NAC Lots-O-Post Thread aka North America Home Owners Association Thread

Beat you Adam
 
Re: THe NAC Lots-O-Post Thread aka North America Home Owners Association Thread

80hp
120 ft. lbs.
 
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