5.7GLI slight vibration at idle and knocks 2500-3300 rpm

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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by TexasCobaltGuy »

Big Block Power wrote: Sat Apr 18, 2020 6:43 pm That's great news on the engine. I would pull the engine to replace the pwr str line it's much easier that way.
Without seeing how those lines are ran I can't help much. It could just be a loose hose clamp. But sure of that system has a pwr str cooler but mine leaked at that fitting and I just added a second clamp to help it out. Keep us up to date and congrats on getting back out on the water.
It does appear to be that exact issue. Made the mistake of removing it entirely to inspect it And now in the process of reassembling it but man what a nightmare it is so tight back there.

The issue appears to be the plastic hose clamp was stripped out so it didn’t squeeze it tight enough on the hose from the pump. In the process of adding stainless steel hose clamps to replace the plastic ones.
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by Big Block Power »

TexasCobaltGuy wrote: Mon Apr 20, 2020 7:08 am
Big Block Power wrote: Sat Apr 18, 2020 6:43 pm That's great news on the engine. I would pull the engine to replace the pwr str line it's much easier that way.
Without seeing how those lines are ran I can't help much. It could just be a loose hose clamp. But sure of that system has a pwr str cooler but mine leaked at that fitting and I just added a second clamp to help it out. Keep us up to date and congrats on getting back out on the water.
It does appear to be that exact issue. Made the mistake of removing it entirely to inspect it And now in the process of reassembling it but man what a nightmare it is so tight back there.

The issue appears to be the plastic hose clamp was stripped out so it didn’t squeeze it tight enough on the hose from the pump. In the process of adding stainless steel hose clamps to replace the plastic ones.
I double clamped mine. No need to remove anything. Just loosen the clamp all the way and slide it on then tighten it down.
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by TexasCobaltGuy »

got new stainless steel clamps on it they are nice and tight... while I got that area opened up I am going to kick off the addition of a battery switch and ACR. Want to get things ready to redo my stereo system in the near future, want to upgrade the entire system so that is going to be a big job as well!
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1997 Cobalt 200 5.7GLI DP
“Alexica Jean”
White with Hunter Green stripe
Mt Vernon, Texas
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by Big Block Power »

Good job. Nice easy fix.
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by AsLan7 »

.
Easy fix and great pics documenting it. Thanks TCG. 8-)

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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by okielaker »

Good documentation. Good pics. One question:

WTH was Cobalt thinking... plastic clamps...? Compromise something?
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by Big Block Power »

okielaker wrote: Wed Apr 22, 2020 11:59 am Good documentation. Good pics. One question:

WTH was Cobalt thinking... plastic clamps...? Compromise something?
I'm not l sure they are plastic clamps. Mine were a factory crimp style. You couldn't tighten them up.
Plus that might be a Volvo thing more than Cobalt. Or blame Malibu!!
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