97 hardbody excessive blow by

Forum for the Xterra, Frontier and Hardbody, the smaller workhorses of the Nissan lineup!
727G35
Posts: 60
Joined: Mon May 20, 2019 6:38 pm
Car: 03 5at g35 sedan

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I bought a 97 hardbody with a ka24e and a 5 speed transmission.
It has heavy blow by, I'm going to compression test it tomorrow, but it wouldn't surprise me if it had piston ring issues.
I figure if there is, I'd be better off(cheaper and less work) getting a new engine rather then fixing this one.
If I put in a ka24de, will I only have to being the fuse box with the harness, and it will drop right in?
Will a ka24e from a 240sx drop in and work on the original harness?
I'm pretty sure its rings, there is a lack of power, but it does need a tune up, which I might as well skip.
All help is appreciated!!


727G35
Posts: 60
Joined: Mon May 20, 2019 6:38 pm
Car: 03 5at g35 sedan

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Also what about a ka24de from a frontier? Or is the 240sx a better start?

whomadewho
Posts: 523
Joined: Mon Aug 02, 2010 9:32 pm
Car: 1997 Nissan pickup

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Possibly the PCV valve is bad or the hose is clogged which can cause excess blow by? The valve is located (passenger side) between the the alternator/oil filter area. Did you check for stored engine codes? Also if the exhaust system is restricted this could also cause excessive blow by and a lack of power? Check the swirl valve located in the intake manifold could be stuck or sticking?

727G35
Posts: 60
Joined: Mon May 20, 2019 6:38 pm
Car: 03 5at g35 sedan

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Awesome thank you I will go check that now!
Now if it is the piston rings or valve seals that's causing the problem is there a way to see if it's the valve seals vs the piston rings? A head would be much easier to change.

whomadewho
Posts: 523
Joined: Mon Aug 02, 2010 9:32 pm
Car: 1997 Nissan pickup

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Try doing a dry compression. If you get a low reading put 1 teaspoon of oil in that particular cylinder and recheck the compression (wet check) the compression should rise but if it’s an excessive amount this would indicate bad rings.

727G35
Posts: 60
Joined: Mon May 20, 2019 6:38 pm
Car: 03 5at g35 sedan

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145
130
140
145
That's my compression.
Not sure why theres so much air coming out.
3 out of 4 plug wires broke when removing them for the test. I'm going to replace plugs and wires now.

whomadewho
Posts: 523
Joined: Mon Aug 02, 2010 9:32 pm
Car: 1997 Nissan pickup

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The numbers are just ok. Given the year I would leave it alone. You mentioned air coming out if this is when the oil filer cap is removed this is perfectly normal. Usually after removing it with the engine running after cleaning up the mess you won’t try it again.

727G35
Posts: 60
Joined: Mon May 20, 2019 6:38 pm
Car: 03 5at g35 sedan

Post

That was on a cold engine without squirting any oil in it.
What's great numbers for this engine?
I'm going to test tomorrow after waming up and doing the 2 quirts of oil

whomadewho
Posts: 523
Joined: Mon Aug 02, 2010 9:32 pm
Car: 1997 Nissan pickup

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Might want to disconnect the fuel pump relay located under the hood passenger side before taking compression. The relay is clearly marked on the cover. Run engine before checking compression.

727G35
Posts: 60
Joined: Mon May 20, 2019 6:38 pm
Car: 03 5at g35 sedan

Post

whomadewho wrote:
Tue Mar 17, 2020 3:56 am
Might want to disconnect the fuel pump relay located under the hood passenger side before taking compression. The relay is clearly marked on the cover. Run engine before checking compression.
howcome? will the fuel sitting damage it?
i already tested it but for now on ill start doing that.


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