Jump to content

KA24DE from a 1999 Nissan Frontier -- Stuck intake valves, WTF!?


mhub91

Recommended Posts

So I ended up getting a KA24DE from my friend for free. He got it from a guy who said it was a "$100 junkyard engine that has been laying around for a while".

 

Tonight, I decided to begin disassembling it to see what i'm getting into. 

 

Spark plugs removed, I placed my thumb over each tube and cranked it over with a ratchet - no compression in any of the cylinders. 

 

I decided to pull the intake off to take a look down in the cylinders and at the valves to see what was the possible cause. I found that all 8 of the intake valves are stuck 3/4 of the way open. The cam also only makes contact at the tip of the lobe.

 

What the hell causes ALL of the intake valves to stick?! 

 

I'm thinkin 1 of 2 things happened. 

 

1 - rust, corrosion, or some other buildup has caused the valves to stick, but this makes me wonder why only the intake and not exhaust, too? Note that the valve cover is missing. Who knows how long it's been missing?

 

2 - the KA is an interference engine; have all the intake valves struck a pistion, bending them? :confused:

 

 

Look like I'll be pulling the head on this one soon. :thumbup:

Link to comment
  • Replies 11
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Probably stored outside on it's side in the rain. Take the intake cam off and turn to TDC #1 so the valves would normally be open on #2 and #3 cylinders. Tap #2 and #3 intake valves with a hammer and block of wood. This should dislodge them and make them pop back up. Now rotate the engine ONE turn and do #1 and #4 intake valves.

 

Might want to tap these valves many times to knock of any rust on the valve a seat faces and get a good seal. Truth is if the stems were that rusty the valve faces are probably toast..

Link to comment

Probably stored outside on it's side in the rain. Take the intake cam off and turn to TDC #1 so the valves would normally be open on #2 and #3 cylinders. Tap #2 and #3 intake valves with a hammer and block of wood. This should dislodge them and make them pop back up. Now rotate the engine ONE turn and do #1 and #4 intake valves.

 

Might want to tap these valves many times to knock of any rust on the valve a seat faces and get a good seal. Truth is if the stems were that rusty the valve faces are probably toast..

 

Well, to tell you the truth, I planned on rebuilding this engine. I got it for free, so putting a few dollars into it isn't too big of a deal. 

 

I made this post to get an idea of what could have happend.

 

I completely agree that if the guides / valves are corroded enough to make them stick this bad, they are toast. 

Link to comment

If you turned it by hand you're ok. Piston only tops out at TDC and cam lobe has passed and not holding valve open. The piston would push the valve closed to where it can pass below it.

 

You're obsessing.... take it apart. :lol:

  • Like 1
Link to comment

hahaha, I'm pretty bad about automatically going to "worst case scenario", it's in my nature.

 

 

Mike, I have a few things to pick your brain about.....

 

I've always wanted to build a "frankenstein engine" with various L, Z, KA parts. Here's what I have right now:

 

KA24E pistons, rods (slight dish pistons, 1990/91 S13 engine)

KA24DE engine (Frontier engine, single row timing chain) 

Z24i engine

Z22 block

Z22 crank

L20 block

L20 pitons, rods.

 

Also have some CRAZY domed 11.5:1 KA24 pistons!!! Venolia brand.

 

I've referred to Jason Gray(?) info and seems like 2.3L big bore LZ23 would be easiest.

Link to comment

2.3 yes. Z22 bored 2mm or L20B block bored 4mm, Z22 crank, Z22 or L20B rods (are the same if early Z22)

 

Keep only the Z22 block/crank/rods//KA pistons for everything else put L20B parts on.... timing cover/oil pan/head/engine brackets/manifolds... everything.

 

S13 or D21 pistons will work. Press piston pins onto the L20B/Z22 rods.

 

Byron on The Realm has one with cam and side drafts makes 135RWHP. Stock 2.3 should be good for 115-120hp with down draft 32/36.  

Link to comment

Unfortunately, my Z22 block has the infamous crack across the head bolt / water passage near cyl 2 and 3. Can this be repaired? OR - can I use an ARP stud kit to ensure I don't damage the area even further?

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.