D21 with a KA24E intake removal

Forum for the Xterra, Frontier and Hardbody, the smaller workhorses of the Nissan lineup!
SolowKaver
Posts: 18
Joined: Sat Mar 07, 2020 4:19 pm
Car: 97 Hardbody 4X4

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Getting ready to pull the head off my '96 D21. Head gasket is shot after overheating. Head is probably warped too. I'm also going to replace the timing chain and gears while it's apart. I've got all the intake bolts and nuts off and it moves a bit but I can't pull it off the head studs. I have disconnected some coolant hoses to the intake. Is there a brace under the intake that I can't see? I left most of the wiring etc. on so far except for the injectors and the connections to the distributor. I'm trying to disassemble and unplug as little as possible. Any advice? TIA


SolowKaver
Posts: 18
Joined: Sat Mar 07, 2020 4:19 pm
Car: 97 Hardbody 4X4

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Found the bracket next to the oil filter. Two 13mm bolts holds it firmly in place. Hard to spot from above. At least I can pull the intake off the head now....

SolowKaver
Posts: 18
Joined: Sat Mar 07, 2020 4:19 pm
Car: 97 Hardbody 4X4

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Update: after wrestling with loosening the EGR tube, the exhaust manifold, the dipstick mount, and the rather stiff intake manifold I finally yanked the head. As suspected the head gasket was toast - the two center webs had 1/2" of missing gasket material. The head is warped upwards by about 0.005" near the middle of the casting. I may try to have it surfaced and slap it back on with a new head gasket.

Question: the warp in the head likely affects the straightness of the cam towers/bearings causing a slight bend in the rotating cam. Is this a problem and if so how can it be fixed?

NCSlagle
Posts: 4
Joined: Wed Jan 15, 2020 8:04 am
Car: 1997 Hardbody, KA24E, 2wd automatic

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I would imagine it would be a problem for anything to be crooked or warped, sounds like something that would cause rods to bend or break. I have taken the cylinder head from a civic and had it resurfaced and it worked fine. I do not know about Nissan.
Hopefully, someone that knows more than I will chime in.
Best of luck!

SolowKaver
Posts: 18
Joined: Sat Mar 07, 2020 4:19 pm
Car: 97 Hardbody 4X4

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I was able to easily rotate the cam after removing the rocker shafts/rockers with no apparent binding or tight spots. This should indicate that the portion of the head mounting the cam towers did not warp too much to cause an issue so I am convinced I am OK on that. I resurfaced the gasket surface and eliminated the warpage using a technique of employing a very flat surface with several lengths of 80 grit sand paper contact cemented on it. The weight of the head allowed me to sand the surface flat checking with a long precision straight edge and feeler gages from time to time. After the surface was flat I switched to 120 grit to get a better surface finish. Looks great and it's flat to 0.001" in every direction. There's a youtube video of a guy doing this that was helpful but having worked with machinists and engineers for decades I knew what to look for and how to check for flatness etc.

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AZhitman
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Joined: Mon Apr 29, 2002 2:04 am
Car: 58 L210, 63 Bluebird RHD, 64 NL320, 65 SPL310, 66 411 RHD, 67 WRL411, 68 510 SR20, 75 280Z RB25, 77 620 SR20, 79 B310, 90 S13, 92 SE-R, 92 Silvia Qs, 98 S14.
Location: Surprise, Arizona
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Sounds like it's coming along!

Since checking compression now isn't happening, might not be a bad idea to re-ring it. You're already tearing it down...

Remember, can't get things too clean - take your time and it'll be good for 200k more miles!

SolowKaver
Posts: 18
Joined: Sat Mar 07, 2020 4:19 pm
Car: 97 Hardbody 4X4

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Thanks AZ... I might do that as well. Looked into new valve stem seals too but they're kinda pricey and I don't think the old ones are leaking (no signs of oil on valves or combustion chamber etc.).

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AZhitman
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Posts: 71061
Joined: Mon Apr 29, 2002 2:04 am
Car: 58 L210, 63 Bluebird RHD, 64 NL320, 65 SPL310, 66 411 RHD, 67 WRL411, 68 510 SR20, 75 280Z RB25, 77 620 SR20, 79 B310, 90 S13, 92 SE-R, 92 Silvia Qs, 98 S14.
Location: Surprise, Arizona
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Excellent. If you do, i think i have a set, as well as some spare gaskets that i didn't use.

SolowKaver
Posts: 18
Joined: Sat Mar 07, 2020 4:19 pm
Car: 97 Hardbody 4X4

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Getting ready to pull the short block for a new clutch. Any tricks to maneuvering it off the transmission (manual) with that really deep oil pan? It looks like it's kinda tightly packed around the front axle to me. When I get it out I'll do some other work on it and bolt on the head prior to slapping it back in.

SolowKaver
Posts: 18
Joined: Sat Mar 07, 2020 4:19 pm
Car: 97 Hardbody 4X4

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The short block was horrible to remove. I had to disassemble nearly all of the mounts, drive shafts, and anything attached to the front axle as well as remove the bolts on the tranny cross-member. It was almost miraculous that there was just enough clearance to jerk the engine loose (it took all day long). I feel like I abused the input shaft bushing in the process (will replace of course). I found some rust on the flywheel and rust particles in the bell-housing. The 220,000 miles on the original clutch was apparent but it still had some surface material left. I fear trying to reinstall the engine once I'm ready. It's going to be an epic battle... Why would anyone design things this way? Terrible design for maintenance for sure!

SolowKaver
Posts: 18
Joined: Sat Mar 07, 2020 4:19 pm
Car: 97 Hardbody 4X4

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I ended up popping the drivers side steering idle arm bar loose from the Pittman arm to help get a few inches more room to pull the front axle forward. This would have helped on engine removal as well. I bolted on the "machined" head, installed a new timing chain etc., clutch - pressure plate - flywheel and managed to slip it back in without destroying anything. The clutch assembly was all rusty (still had friction material left!) and the flywheel had lots of surface cracks so they were replaced along with the throw out bearing. The sealant on the bell housing must have caused moisture to remain inside rusting everything inside. I made sure the drain slot was clear of factory sealant on assembly. Spent a day reassembling everything underneath and bolting up the intake, attaching coolant hoses and snapping all the sensor connectors back on. I shot some light oil in each cylinder and turned the engine over to prime the oil pump since it was out for awhile. Popped in the plugs and turned it over without the cap and wires for a bit. Sounds healthy on the compression - about like it used to (I may do a compression check later for the grins). I need to finish MIG welding up the crack on the exhaust manifold (welding in very short bursts skipping an inch or two etc. until it gets all covered up) before I install it and fire it up for several seconds to see how she runs. Then I'll bolt on all the accessories on the front of the motor and slap in the new radiator to finish up. It's been a long journey - glad I'm not in a hurry. Thanks for all the help guys!

SolowKaver
Posts: 18
Joined: Sat Mar 07, 2020 4:19 pm
Car: 97 Hardbody 4X4

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Engine is in and running. I managed to fry a fusible link after leaving the battery connected and installing the alternator (right after starting it for the first time to see if it would run and before I put all the accessories on etc.) so I still have to fix that before a test drive. After installing everything I filled it full of coolant and ran it awhile. White steam was blowing out the tailpipe! I soon realized it was from left over water in the exhaust system from when the head gasket blew. What a relief when it all cleared up. I noticed some heavy valve rocker noise on one valve though. It had some noise before I warped everything but it seems worse now. As far as I can determine there is no rocker arm adjustment for this issue. New rocker arm(s) maybe? The cam looked fine when I inspected it on disassembly so it likely isn't that. Need to set the timing as well but it sounds pretty smooth so far.

SolowKaver
Posts: 18
Joined: Sat Mar 07, 2020 4:19 pm
Car: 97 Hardbody 4X4

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Fixed the fusible link, tweaked the timing and test drove her around the neighborhood. So far the engine performs well and seems to be OK. The rocker arm is still making lots of noise. After finding some replacement parts online I realize it has built in hydraulic lifters (duh). Does anyone have advice on un-sticking the lifter or do I find the culprit and replace it?


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