Lt1 Loud Knock Won't Start Banging
 

My LT1 won't start at this point. After I installed a new pressure plate this all happened. Not sure if its just coincidence. After I reinstalled the tranny and a new poly mount I took it for a ride. It ran mint for about an hour and two 10mph launches. After another 100mph pass It started to hesitate or miss for a second and then pull again while driving home. So I thought it was a rocker too tight or something. After checking the rockers I put it back together and drove it last night for about 10 minutes before I started to get a loud banging when under a load. So I brought it home and left it to look at this morning. I just went out to start it and it just cranks over and bangs A LOT. Could this be a spun bearing, rod knock, broken crank or is something binding with the tranny?

Pull the trans and see if anything came apart in the bellhousing. If nothing there pull the oil pan. You'll find your problem :)

probably the trans do what he says then do this

drain the oil from the pan and check for metal shavings a lot of shaving if any.

well i really hope its the tranny, anyone else have any ideas?

If it was the tranny, why would the engine not continue running?

How many miles? Is it knocking consistant with RPM's, or is it sparratic? Does it sound like it's in the Engine and is it on a specific side..

motor has less then 10k miles, im not sure the car will only start and run while giving it gas

also i want to add when putting the tranny back in it went in till about 5 inches away, then I popped the fork into place then push it in another 3 inches. at this point i was about 1-2 inches from the tranny touching the bellhousing so I put the bolts in and tightened down to snug the tranny up...this was probably stupid but the car ran fine for a 30 minute trip like that. also if the clucth is all the way to the floor on startup and held there how could the tranny have any effect on the motor?

also i here A LOT of ypipe banging on the floor

Is the Engine rocking around like it wants to jump out?

yea i would say so

Probably a Spun Bearing.. mine did that when I spun it. It was screetching too..sounded like it was going to explode..lol

Check that oil pan, see if the engine left you any shiney gifts....

drain the oil already

Check that tranny, you probably fried your T/O bearing or your pilot bearing if the tranny was not properly seated. You NEVER NEVER NEVER want to use the tranny bolts to pull it together, it should always slide completely together and then tighten down. If the input shaft did not seat properly this probably your problem, and when you have the tranny back out check that input shaft as well to see if the end is chewed up. Let us know what you find.

ok I will drain the oil today then let you know...i hope its still the tranny but I will start with the easiest first

just drained oil...dont see anything yet...im going to run it through a coffee filter

I'd have just used a magnet (if you throw away speakers, not bad to rip the magnet off), but that should work good.

I'd say it's trans related due to the issues you had with installing.

Try putting the car in neutral then push the switch under the clutch pedal and try to start. By starting this way, you eliminate the fork contacting the pressure plate issue. If it starts right up and sounds decent, shut it back off and pull the slave and the alumium cover so you can get to the fork. Look at the bolt that holds the fork in (fulcrum point) and see if it looks like it's backed out. If so, that's your problem. If it is this, you can use a LONG wrench to get in there and tighten it without pulling the trans. If the engine still makes noise, I'd suspect the engine has issues; what's your oil pressure now?

This is the only real trans related thing I can think of that would cause this right after R&Ring the trans. I've seen it a couple times and it definitely makes a TON of noise.

Ryan

Whats the results with the magnet/coffe filter? Anything come up?