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

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

Post by Big Block Power »

akorcovelos wrote: Sat Apr 04, 2020 9:35 pm Don’t put those manifolds back on that engine. Does it look like it was leaking inside the water jacket? Is that the same side as the low cylinder?
Yea I think both sides were low if I remember correctly from the middle 2 cyl.
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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 04, 2020 10:33 pm
akorcovelos wrote: Sat Apr 04, 2020 9:35 pm Don’t put those manifolds back on that engine. Does it look like it was leaking inside the water jacket? Is that the same side as the low cylinder?
Yea I think both sides were low if I remember correctly from the middle 2 cyl.
Yes the side that both had 30psi that exhaust gasket was blown out between the 2 exhausts for 3 and 5.


I will post many more pictures Sunday as I get the intake and heads off. If the cylinders have signs of damage and wear. I will
Have to figure out how to pull the engine and take the whole thing to the shop on Monday. Fingers crossed that isn’t the case.
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by TexasCobaltGuy »

The 4-6 cylinders one was 90 and other was like 40
If my memory is correct.
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by TexasCobaltGuy »

Researching and I found a riser kit. Anyone know if this riser kit will fit with these manifolds I got a quote from dealer for replacing mine. Manifold PN 3847501. Riser kit PN 3862907 which includes these risers PN 3862627
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by akorcovelos »

TexasCobaltGuy wrote: Sun Apr 05, 2020 10:07 am Researching and I found a riser kit. Anyone know if this riser kit will fit with these manifolds I got a quote from dealer for replacing mine. Manifold PN 3847501. Riser kit PN 3862907 which includes these risers PN 3862627
Replace the riser and manifold.
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by Big Block Power »

TexasCobaltGuy wrote: Sun Apr 05, 2020 10:07 am Researching and I found a riser kit. Anyone know if this riser kit will fit with these manifolds I got a quote from dealer for replacing mine. Manifold PN 3847501. Riser kit PN 3862907 which includes these risers PN 3862627
I guess compare the prices to the internet. There is plenty out there.
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by TexasCobaltGuy »

Intake off. Starting on the heads next. Creating a board to keep track of order for rods and rockers
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by TexasCobaltGuy »

akorcovelos wrote: Sun Apr 05, 2020 11:03 am
TexasCobaltGuy wrote: Sun Apr 05, 2020 10:07 am Researching and I found a riser kit. Anyone know if this riser kit will fit with these manifolds I got a quote from dealer for replacing mine. Manifold PN 3847501. Riser kit PN 3862907 which includes these risers PN 3862627
Replace the riser and manifold.
Looks like the new riser is much taller ~3 inches. Is there a kit to extend the exhaust tubes to match up to the new height?
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by akorcovelos »

TexasCobaltGuy wrote: Sun Apr 05, 2020 12:01 pm
akorcovelos wrote: Sun Apr 05, 2020 11:03 am
TexasCobaltGuy wrote: Sun Apr 05, 2020 10:07 am Researching and I found a riser kit. Anyone know if this riser kit will fit with these manifolds I got a quote from dealer for replacing mine. Manifold PN 3847501. Riser kit PN 3862907 which includes these risers PN 3862627
Replace the riser and manifold.
Looks like the new riser is much taller ~3 inches. Is there a kit to extend the exhaust tubes to match up to the new height?
I don’t know a ton about VP specific stuff, but I do recall a thread here that talked about a redesign on the manifold/riser and I believe the new risers when paired with the new manifold align the exhaust tubes to stock location. One of VP folks here should be able to confirm.
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by Big Block Power »

The rockers should be able to stay on. Just loosen them up to get the push rods out. The risers would only be taller to prevent reversion. You want them to be at least 14 inches above the water line. Taller is fine if they all match up. Other wise no.
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by TexasCobaltGuy »

One of the articles I read recommend removing them so I went ahead and created a box to hold them with numbering.

Also I created a similar board for the 17 screws in the head. One video I watched recommended new screws for the heads when I reassemble. Any opinions on that as a good practice? Thx
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by TexasCobaltGuy »

1 3 5 7 head is out and sure enough the head gasket blew between 3 and 5. The bear was getting the power Steering cable retainer that is screwed on to the back of the head. What a nightmare that was to get off.

Anyway, all things considered the cylinders look great in my opinion. To keep them from rusting I wiped them down with some old oil from the engine. And covered with an old shirt with oil on it.

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

Post by Big Block Power »

No you don't have to replace the head bolts. They are not torque to yield bolts. Also get some liquid Teflon pipe thread compound. I know you will put that on the intake bolts. So wire wheel all of the bolts first. It's been awhile but I think I used it on all of the head bolts as well. Matt and akro can confirm that.
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by cmattj »

Yep white liquid Teflon with PFTE is what I use.
Doesn’t effect torque specs, and seals threads great. Especially if antifreeze is used. ( this is fresh cooled so no worries)

Permatex and LocTight is a local brand. Auto zone.
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Re: 5.7GLI slight vibration at idle and knocks 2500-3300 rpm

Post by Big Block Power »

cmattj wrote: Sun Apr 05, 2020 3:35 pm Yep white liquid Teflon with PFTE is what I use.
Doesn’t effect torque specs, and seals threads great. Especially if antifreeze is used. ( this is fresh cooled so no worries)

Permatex and LocTight is a local brand. Auto zone.
Yea I thought so. I can picture it in my head. I think it's obvious once you take out the bolts as it's on the bolts that you have to clean off.
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