Start up problem 408
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From: Bakersfield, Ca
Start up problem 408 (broken PRC head) I just got the 408 into my car, hooked everything up and tried to prime the engine, it cranks over once and looses power to the entire car, but power comes back immediately, then it cranks again and looses power and so on. The battery is fully charged, all of the grounds are hooked up. I tried adding another ground from the block to the body, and the block to the battery, and hooked up another hot wire from the battery to the starter. Im running out of ideas on what it could be. Any thoughts?
Last edited by dragon93308; Sep 19, 2006 at 10:51 PM.
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From: Detroit, MI - Camp Pendleton, CA
Make sure all of your grounds are clean. Its definately high resistance somewhere in a main cable. Make sure your starter draw isnt too much. Second, how long did the battery sit? It may need to trickle charge over night if it sat too long. Tighten up that ground at the battery.
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From: Bakersfield, Ca
Battery was working in another car until i put it in the vette today. I tried putting the charger on it for an hour and nothing happend. Il try cleaning up the grounds.
Maybe a stupid question but the car isnt just dying after start up is it? I mean on a H/C tune in my car with the 408 it would start then die, then restart then die until I sorted out a good tune... Its prolly not your issue but I was just checking.... Good luck
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From: Nebraska City,Nebraska
I just finished installing a 408 in my vett. It's sounds like the wires on the starter are not hooked up right. Make sure that they are in the right place because it will cause the problem you are having. Second any wiring in the install that is not hooked up right or has a problem will cause feed back in these cars. I have found out the hard way on more than once. There are three important hook ups that can cause the car to not to turn over. One the crank position sensor, two the cam positions sensor, and one that most do not think of (me) oil level sensor. I had the wire to this sensor get to hot from the headers and the car would not start and would not turn over at one point when they where grounded together. So check these and hope you find your poblem soon. 
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From: Bakersfield, Ca
Well i figured out what the starting problem was, it was just a ground on the starter.
I started the motor and it sounded sweet, for about 30 secconds, then a horrible clacking sound. Thinking the worst i took off the passenger side valve cover and found this
Those are TSP PRC stage 1 heads with the valve job. Brand new heads. I feel sick.
I started the motor and it sounded sweet, for about 30 secconds, then a horrible clacking sound. Thinking the worst i took off the passenger side valve cover and found this
Those are TSP PRC stage 1 heads with the valve job. Brand new heads. I feel sick.
Last edited by dragon93308; Sep 19, 2006 at 09:52 PM.
WOW. That's some sickening stuff right there. I'm sure you've contacted them already. Let us know how it goes. Hopefully nothing got down into the chambers and scarred anything up 
Damn, that makes me sick just looking at that picture. Never seen that before. At least it didn't run long. I would send them back and go buy another brand head better suited for a 408.
Last edited by DrkPhx; Sep 19, 2006 at 11:24 PM.
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From: Bakersfield, Ca
Originally Posted by Pro Mouse
Ouchie ,that sucks ,look like a bad casting
You may want to double check that your pushrods are not too long. Did you verify PV clearance? Only reason I ask is because either will put too much stress on the rocker and break the rocker or the head as what happened to you.
