KA24DE ring gap question, should I pull my engine apart?

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Akuhyo
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Car: 1990 Nissan 240SX Hatch

KA24DE ring gap question, should I pull my engine apart?

Postby Akuhyo » Tue Mar 02, 2021 7:02 am

I recently built my KA but I did something kind of stupid- I didn't check the ring gap when installing the piston rings. Should I be okay? This is gonna be an NA motor.

I have no idea if my rings came pre-gapped or not, they were DNJ piston rings. They went in without a problem- no trouble installing them. Should I be worried about this? I emailed them and tried calling them but no answer. I did a light honing of the cylinder walls prior to installation. People are telling me I'll be fine since rings usually come pre-gapped for their application, and others say regardless of the gap I should be fine since it's gonna be an NA motor.

Will I be fine?


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VStar650CL
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2004 Nissan Altima 2.5 S

Re: KA24DE ring gap question, should I pull my engine apart?

Postby VStar650CL » Tue Mar 02, 2021 7:56 am

Akuhyo wrote:
Tue Mar 02, 2021 7:02 am
Will I be fine?
Very likely. Machine tolerances are way better than they were in the bad old days, and that goes for reputable aftermarket parts too, not just OE. If the rings were the right ones for your application, the chances of getting a tight one are someplace between slim and none. Tight clearance is what can really hurt you in terms of wear or failure. Loose tolerances can hurt too, but generally only in high-compression or boosted applications. For an NA application, the effect of loose clearance will generally be minimal-to-none.

Akuhyo
Posts: 15
Joined: Fri Jan 08, 2021 7:43 am
Car: 1990 Nissan 240SX Hatch

Re: KA24DE ring gap question, should I pull my engine apart?

Postby Akuhyo » Tue Mar 02, 2021 8:41 am

VStar650CL wrote:
Tue Mar 02, 2021 7:56 am
Very likely. Machine tolerances are way better than they were in the bad old days, and that goes for reputable aftermarket parts too, not just OE. If the rings were the right ones for your application, the chances of getting a tight one are someplace between slim and none. Tight clearance is what can really hurt you in terms of wear or failure. Loose tolerances can hurt too, but generally only in high-compression or boosted applications. For an NA application, the effect of loose clearance will generally be minimal-to-none.
Yeah I'm mainly worried for tight clearances, thinking on buying an ISR rad to help with cooling so nothing heats up too much in there. (running stock rad)

I'm just hoping the gap is either stock or at least big enough to where the ends wont butt when heated up. This is my first car & first engine I've ever rebuilt which is why I'm so worried.

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VStar650CL
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2004 Nissan Altima 2.5 S

Re: KA24DE ring gap question, should I pull my engine apart?

Postby VStar650CL » Tue Mar 02, 2021 9:27 am

Akuhyo wrote:
Tue Mar 02, 2021 8:41 am
Yeah I'm mainly worried for tight clearances, thinking on buying an ISR rad to help with cooling so nothing heats up too much in there. (running stock rad)

I'm just hoping the gap is either stock or at least big enough to where the ends wont butt when heated up. This is my first car & first engine I've ever rebuilt which is why I'm so worried.
If you want to take precautions, an oil cooler will serve you better than a bigger radiator. The pistons, especially the crown areas, are cooled primarily by oil coming out the spit-holes.

Akuhyo
Posts: 15
Joined: Fri Jan 08, 2021 7:43 am
Car: 1990 Nissan 240SX Hatch

Re: KA24DE ring gap question, should I pull my engine apart?

Postby Akuhyo » Wed Mar 03, 2021 5:24 am

VStar650CL wrote:
Tue Mar 02, 2021 9:27 am
If you want to take precautions, an oil cooler will serve you better than a bigger radiator. The pistons, especially the crown areas, are cooled primarily by oil coming out the spit-holes.
Hmm yeah I will probably get an oil cooler now.

Kind of relieved at the fact that the chances of getting tight rings are low, just hoping nothing bad happens.

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VStar650CL
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Re: KA24DE ring gap question, should I pull my engine apart?

Postby VStar650CL » Wed Mar 03, 2021 5:34 am

Akuhyo wrote:
Wed Mar 03, 2021 5:24 am
Kind of relieved at the fact that the chances of getting tight rings are low, just hoping nothing bad happens.
The chances are lower than low if the rings were the right p/n, tolerances on rings from any reputable source these days are in ten-thousandths. The primary risk is of a mis-packed product that was oversize.

Akuhyo
Posts: 15
Joined: Fri Jan 08, 2021 7:43 am
Car: 1990 Nissan 240SX Hatch

Re: KA24DE ring gap question, should I pull my engine apart?

Postby Akuhyo » Wed Mar 31, 2021 2:19 pm

VStar650CL wrote:
Wed Mar 03, 2021 5:34 am
Akuhyo wrote:
Wed Mar 03, 2021 5:24 am
Kind of relieved at the fact that the chances of getting tight rings are low, just hoping nothing bad happens.
The chances are lower than low if the rings were the right p/n, tolerances on rings from any reputable source these days are in ten-thousandths. The primary risk is of a mis-packed product that was oversize.
This is a late reply but by p/n do you mean part number? I didn't get the rings from an OEM nissan supplier but the rings were from DNJ rock. It's starting to become time to finally start my KA, I'm just afraid those rings are gonna butt ends.

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VStar650CL
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2004 Nissan Altima 2.5 S

Re: KA24DE ring gap question, should I pull my engine apart?

Postby VStar650CL » Wed Mar 31, 2021 3:41 pm

Akuhyo wrote:
Wed Mar 31, 2021 2:19 pm
This is a late reply but by p/n do you mean part number? I didn't get the rings from an OEM nissan supplier but the rings were from DNJ rock. It's starting to become time to finally start my KA, I'm just afraid those rings are gonna butt ends.
Yep, p/n is part number.


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