help - i screwed up on my v8 - advice needed |
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help - i screwed up on my v8 - advice needed |
jimkelly |
Feb 9 2016, 01:31 PM
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#1
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Delaware USA Group: Members Posts: 4,969 Joined: 5-August 04 From: Delaware, USA Member No.: 2,460 Region Association: MidAtlantic Region |
last week we determined that some of my oil leak problem was 4 bolts holding my carb intake to the heads, so we applied sealant and 3 stopped leaking. on Saturday I thought i'd address the last one that did not stop leaking, so not only did I add sealant to it again, I decided to use a longer bolt because the other 3 were longer. I used a 1.5" bolt but it turns out the other were probably 1.25", the max that should be used. so anyway, monday go for a drive but power is weird, I figured it had to do with engine being cold and I just changed the fuel filter and thought maybe there was some starving going on, but 30 minutes later I decided to go back home and figure out what was wrong. anyway, yesterday I pull the valve cover off to find a cracked valve rod that I retrieved from the head with a magnet on a stick but I had to remove the intake to put the lifter back in the head. anyway, it is all back together but it revs ok in neutral but under load it is either valves or knocking. what you think? anyway, why does a guy with so little mechanical prowess own a 914, who the hell knows. i'd like to think the noise is due mostly to timing cause I of course had to pull the distributor. and I never put a tdc mark on my flywheel or crank balancer, need to, asap. I first thought it was vacuum advance problem but vacuum is pulling thru hose.
https://www.youtube.com/watch?v=tfKEa1-W0XQ video is being loaded, pls check back and comment. pls pls. Attached thumbnail(s) Attached image(s) |
Bulldog9 |
Feb 9 2016, 07:55 PM
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#2
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Senior Member Group: Members Posts: 705 Joined: 21-August 13 From: United States Member No.: 16,283 Region Association: MidAtlantic Region |
If the intake manifold bolt put enough pressure on the pushrod to cause it to break, there will likely be some sort of problem, damaged lifter/cam lobe, or bent valve because the valve couldn't close, or both.... As far as 'wiped cam' that means the cam lobe is worn out or will give less lift. You can run on that for a while. Not optimum, but not unacceptable either. You could have also destroyed/collapsed the lifter which I assume is hydraulic or bent the rocker arm . THIS is your best hope.
I agree with the comments above, check/replace the lifter, replace the pushrod, and do a compression check. IMO, if its a damaged cam lobe, DRIVE it..... Take your time, Save your $$ plan a build, do it right. If a bent valve well..... (IMG:style_emoticons/default/mad.gif) |
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