Help Diagnose Quad 4 Knock?
Help Diagnose Quad 4 Knock?
So here it is, just purchased this Quad 4 Beretta. Hoping this is just a simple fix, took it to some people and some say rod bearings, main bearings, lifters, and even loose flywheel bolts. So it can be anything to that nature.
I'll probably end up taking this motor apart and plastigauging the bearings. Hoping that is the issue.
So heres the video, sounds kind of distroted the car has no muffler, previous owner had a fartcannon, cut that off as soon as I got home.
http://youtu.be/rxZyFjzsLJY
Engines idles normal oil pressure is good and engine light is not on.
So what do you think?
Thanks.
I'll probably end up taking this motor apart and plastigauging the bearings. Hoping that is the issue.
So heres the video, sounds kind of distroted the car has no muffler, previous owner had a fartcannon, cut that off as soon as I got home.
http://youtu.be/rxZyFjzsLJY
Engines idles normal oil pressure is good and engine light is not on.
So what do you think?
Thanks.

1of 896 Quad4 Z26's....now 3500 5spd swapped!-sold
'14 C7 Z51 7SPD
- SuzukiGhostRider
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Re: Help Diagnose Quad 4 Knock?
There will be no need to bust out the plasti-gauges. That's a spun rod bearing. Probably from improper oiling/no oiling or excessive revving under operating temp.

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Re: Help Diagnose Quad 4 Knock?
I have a quad 4 Z26 too as you can see, and I purchased mine with a couple spun rod bearings... Ick! I fixed mine with junkyard parts for cheap, (but the junkyard quad 4 donor I found had only 19,000 miles, lol)! I used the rods and crank and head from that engine, bought new bearings and a gasket set, new head bolts, etc. and rebuilt it. 10,000 miles later it's still happy! I don't think I've seen another white quad Z26! Welcome! Pics? Where ya from?
'94 Quad 4 H.O. 5 speed Z26, Red & Rare! 1 of 896 Quad Z26's and of those it's 1 of 167 red paint/gray interior!
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Re: Help Diagnose Quad 4 Knock?
Thanks for the help, my thinking as well.
You think I can just put new bearings on it and bandaid it?
Im not going to beat on it, I want to rebuild the engine but want to drive it while I gather all the parts. Its not my daily driver just like 2 days out of the week 5 mile commute round trip...lol I've got my little Colorado for daily driving.
Heres a pic if the car, im more than sure the previous owner neglected the car and beat on it.

You think I can just put new bearings on it and bandaid it?
Im not going to beat on it, I want to rebuild the engine but want to drive it while I gather all the parts. Its not my daily driver just like 2 days out of the week 5 mile commute round trip...lol I've got my little Colorado for daily driving.
Heres a pic if the car, im more than sure the previous owner neglected the car and beat on it.

Last edited by Quad4Z26 on Fri Sep 09, 2011 6:34 pm, edited 1 time in total.

1of 896 Quad4 Z26's....now 3500 5spd swapped!-sold
'14 C7 Z51 7SPD
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Re: Help Diagnose Quad 4 Knock?
You can't just put new bearings in and expect them to last at all... Nothing about the crank or rod will be in spec unless you plan on replacing that rod and having the crank turned properly to accept an oversized bearing. When something like that goes out, it wears all the other parts so a replacement bearing will just spin as well unless you fix all of those other issues and then use an oversized bearing.
Re: Help Diagnose Quad 4 Knock?
This is how the oil looked when I changed it out. Moving it with my finger.



1of 896 Quad4 Z26's....now 3500 5spd swapped!-sold
'14 C7 Z51 7SPD
Re: Help Diagnose Quad 4 Knock?
peanut butter? you need a complete rebuild. If you continue to drive it you are going to put a rod through the block.
Beat it or not the Quad cruises highway speed at 3 grand.
Beat it or not the Quad cruises highway speed at 3 grand.

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Re: Help Diagnose Quad 4 Knock?
Im not driving it, its currenlty parked. I intended to drive it a couple cays during the week, thats not gonna happen. Ill just start buying parts for the rebuild and save myself a headache. I bought this car to restore it, but it was in my plans until next year, I came across this quad4 Z26 and couldn't pass it up, got it for $500. Ill just take it easy on the rebuild.
Thanks.
Thanks.

1of 896 Quad4 Z26's....now 3500 5spd swapped!-sold
'14 C7 Z51 7SPD
Re: Help Diagnose Quad 4 Knock?
Nice buy for 500..

My Motortopia
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Re: Help Diagnose Quad 4 Knock?
As stated, that crank WILL need to be turned. So, no , you will just blow it up hardcore continuing to press your luck.
Biting the bullet and waiting to rebuild, as you seem to be intent on doing, is the correct course of action.
Nice looking Z and the Arctic White is holding up much better than most I've seen.

Biting the bullet and waiting to rebuild, as you seem to be intent on doing, is the correct course of action.
Nice looking Z and the Arctic White is holding up much better than most I've seen.
Re: Help Diagnose Quad 4 Knock?
So dropped the oil pan and was a worn out rod bearing, not spun. The first rod on the passenger side.
I think the rod is out of round, going to buy another rod and have my crankshaft machined.....hope it can be salvaged.
No one within 200miles has this motor or parts!!
Sent from my SGH-T959 using Tapatalk
I think the rod is out of round, going to buy another rod and have my crankshaft machined.....hope it can be salvaged.
No one within 200miles has this motor or parts!!
Sent from my SGH-T959 using Tapatalk

1of 896 Quad4 Z26's....now 3500 5spd swapped!-sold
'14 C7 Z51 7SPD