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Old 09-09-2010, 06:44 PM
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Possible valve issue

Driving and started hearing a knocking type sound pulled over and lifted hood and sound was coming out of carb? I was told it could be valve or timing ? Motor is still fresh less then 100 miles pulled valve cover only found one rocker loose, tried to turn motor on but it pops out carb and will only crack over? Any place to start

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Old 09-10-2010, 01:44 PM
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sounds like your distributor decided to go for a little bit of a spin, reset it to base line and try again and see if it is still popping trough the intake. I'd go from there.
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Old 09-10-2010, 03:53 PM
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Quote:
Originally Posted by truckboy61
Driving and started hearing a knocking type sound pulled over and lifted hood and sound was coming out of carb? I was told it could be valve or timing ? Motor is still fresh less then 100 miles pulled valve cover only found one rocker loose, tried to turn motor on but it pops out carb and will only crack over? Any place to start
I would start with a compression test if it will turn over but not start. If it will start, put a vacuum gage on it and note what you see.

You may have a wiped cam lobe, the valve(s) may be adjusted incorrectly, broken spring, bent pushrod, pulled rocker stud, broken rocker arm, bad vacuum leak, ignition or cam timing incorrect, sheared distributor gear roll pin, etc, etc.
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Old 09-10-2010, 05:23 PM
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Found lifter was completely rounded on bottom was that because they were to tight ? What are chances fragments will damage bottom end ? I plan on changing cam and going solid lifters how do I clean out any fragments?
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Old 09-10-2010, 06:00 PM
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Quote:
Originally Posted by truckboy61
Found lifter was completely rounded on bottom was that because they were to tight ? What are chances fragments will damage bottom end ? I plan on changing cam and going solid lifters how do I clean out any fragments?
Unless you want to be repeating this routine in a few weeks, disassemble the motor down to the bare block and clean out all the shrapnel from all the nooks and crannies (oil galleys). Get yourself a brush kit from Summit that has all the rifle bore brushes and such so you can clean the crank oiling holes. Then install a retro-fit hydraulic roller camshaft and forget it.

If you intend to be hard-headed and try another flat tappet cam after you get it all cleaned out, read through this checklist.....
http://www.crankshaftcoalition.com/w...ips_and_tricks
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Old 09-10-2010, 07:04 PM
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No I plan on using a mechanical roller cam
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Old 09-10-2010, 07:15 PM
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Lifter rounded over because you failed to do the break-in correctly, either in initial set-up or during/after starting, or in not using the correct oil and additives for flat tappets. Look over and follow the link to the checklist TechInspector posted, its all there.

It had nothing to do with valve adjustment.

You're going to need to tear it down and clean it out or you greatly increase the risk of doing it again. There is no easy button fix for this.

When you go back to assembly after cleaning, install the cam and lifters only into the block, rotate cam by hand and make sure that all the lifters rotate while doing this. If some are slow and some are faster, swap those with each other to try to get similar rotation from all. If you have one or more that stay slow or don't really rotate at all, find out why. You may need to hone one or more lifter bores to make things right, that is why I suggest this check before you put any other parts in the block - so you can re-clean it again if you have to hone a lifter bore.
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Old 09-10-2010, 07:20 PM
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Quote:
Originally Posted by truckboy61
No I plan on using a mechanical roller cam
Even if you go to a roller you still need to clean out all the trash from the bad lobe and lifter. A roller lifter will not live long if a piece of left over grit gets into the needle assembly.
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