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RIP (12/27/60-7/18/15)
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767 Posts
Discussion Starter #1
: I had a clanking noise in my motor and was told I needed to figure out what was going on before it blew up...:Scottwax1:
I got the pan and windage tray off and see nothing bad as of yet. I need to pull the plugs and rotate it and look about......
But......uh.........then what?
At a loss here :banghead:
thanks as always
Tk
ps aint never took this beast apart....just built it 1/2 donkeyed (?)
:nopity:
 

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Super Moderator
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5,782 Posts
After you get the pan and tray off, turn it crank side up, see if you can wiggle any of the rods side to side with your hands (you shouldn't be able to, at least not perceptibly). Wiggle the crank back and forth just a little while feeling each rod cap with your fingers. You shouldn't be able to feel anything "hitting", no discernible slack anywhere. Turn it so that one bank of cylinders is "sideways" - turn the crank so that each piston is at the top of the bore, then **GENTLY** tap it on top of the piston will a rubber mallet while feeling the other end. Again you shouldn't be able to feel any slack at all. Turn each one 180 and repeat, tapping **GENTLY** this time on the rod cap. (If you whack too hard on it in either direction, you risk "flat spotting" and ruining the bearing.) If you find one or more that seems to have some "give" in it, that's likely to be where your problem is.
Look inside the windage tray for any evidence that the crank has been hitting it.

If it's still a mystery after all that, then the next step will be to take the bottom end apart and inspect (and measure) all the bearings, also see if you've got a piston pin problem, but don't go down that road just yet until you know you have to. If you DO remove any rod caps, make double-dang sure that you mark everything first so you can put them back exactly where they came from.

Bear
 

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RIP (12/27/60-7/18/15)
Joined
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767 Posts
Discussion Starter #3
Thank you Bear....:cheers. There was no evidence of anything on the windage tray. Kinda thought it might have been the short piece of dipstick tube that the w.tray holds....nope :(

to be continued.......
 

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RIP (12/27/60-7/18/15)
Joined
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767 Posts
Discussion Starter #4 (Edited)
I have the plugs out and am able to wiggle all the rods, by the caps....
I did notice that I can "press down" on all of the pushrods at some point in the cranks rotation and feel the "springiness" of all the lifters.......except the 5th from the front on the right side!......as I rotate the crank that pushrod and valve are moving but theres no springiness felt... got the heads off, the #5 bore and piston top is realy oily.......#1 a little. (would the lifter being "stuck" ruin the cam?)
something tells me a complete dissemble and taking the pistons block and crank into the machine shop is in my future.( when I first built it he looked at the block and heads but not the crank)
:cryin::cryin:
:nopity:
 

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RIP (12/27/60-7/18/15)
Joined
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767 Posts
Discussion Starter #5
Got the heads off and the #5 bore and piston top is really oily.... # 1 a little. Just gonna take the block crank and pistons intact to my machine shop. wondering if they need the lifters? If the one lifter is bad as mentioned above....can I just replace 1 lifter?
thanks as always :)
 

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Super Moderator
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5,782 Posts
Just replacing one lifter traditionally isn't something that's recommended, because the lifter, corresponding cam lobe, pushrod ends, and rocker arm all develop wear patterns at the contact points. Putting in new parts mean those areas have to wear in and mate up with each other again, and that can result it too much wear at those points. That's the "standard answer". Actually (disclaimer: this is just my opinion) I think it kinda depends on the situation. If you're running a "big" cam with "heavy" springs, yeah, I'd probably have to think pretty hard about it. With a more or less factory cam and springs, that were still relatively "fresh", it's probably pretty safe to just replace only the damaged parts --- if that's what it turns out to be.

Being able to move the rods side to side on the crank isn't bad (unless the side clearances are too wide because that can cause low oil pressure), but being able to move them "the other way" (visualize someone ringing a chuckwagon dinner triangle with a metal bar) is.

Bear
 

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Premium Member
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73 Posts
Did you do a compression check prior to pulling it apart? The stiff lifter you describe may be your problem but maybe not. Lifters do not all act the same for example soaking a new set of lifters in oil before you install them you can find one or more that do not have the same resistance when you pump them. That does not mean they are bad but it does mean that you have to pay attention when you are adjusting the preload. Some folks think that you simply keep tightening the rocker till you feel resistance twisting the push rod. It is easy to get too much preload on a soft lifter. They will pump-up when you run the engine but you don't want them too tight. An old drag racing trick is to over tighten the rockers to increase rpm problem for a street car is that will wipe your cam pretty quick.
 

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RIP (12/27/60-7/18/15)
Joined
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767 Posts
Discussion Starter #8
Only have 400 miles on the car and it ran great............block and pistons ccrank and cam (intact are in wifeys jeep. off the the machine shop. gonna take the heads in too.... seems a couple springs arnt the same height as the others :(
this cant happen again
 
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