# Nissan Hardbody skipping new timing assembly constantly



## LowkeySebs (12 mo ago)

Hello everyone! This is actually my first ever written forum so apologies if I mistakenly mess anything up  

here’s my problem. So I have a 1996 Nissan Hardbody KA24E RWD. I rebuilt the top end. Removed inches thick of carbon build up on the head, ported and polished it but to do so I had to remove the valves and retainers, along with put a 240sx intake manifold and deleted emissions. Before buttoning it all together I decided to redo the timing assembly as it always rattled, I opened it up and the guide to the right was broken and sitting in the oil pan with only the metal back remaining bolted on. I bought a cheap eBay kit to fix it and it looked perfect. Lines everything up at top dead center, put the marks on the chain to the crank and cam sprocket marks correctly. Everything was decently firm but I tried rotating the crank by hand with a ratchet and immediately it skipped it at the bottom right of the crank as it’s tight on the tensioner side but the other is extremlyyyyy ridiculously loose. I tried even undoing the cams rockers and moving the fan slightly back in to which got that slack out but once I tried to hand tighten the rocker bolts it then turned super loose yet again. Torqued it back down and moved on to try something else. I figured it’s just cheap parts so I ordered from OEM Nissan the chain and tensioner, replaced the crank sprocket and cam sprocket but kept the cheap eBay guides as I see no problem with that how it could be an issue when it ran on pure metal before. I put the oem tensioner in oil first then placed it on and it’s even worse now. It skips 2 teeth at a time for every quarter turn on the motor by hand. Does anyone know the possible answer as to why it is doing this? No valves seem bent at all and by touch it feels like it has a-lot of compression still. I’ve been trying to get this thing running for 3 years now as I’m a junior in high school and need it to be my cool daily driver since I’m getting my license in a few weeks. Any help I’d really appreciate!


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## jp2code (Jun 2, 2011)

Let me start by saying that I don't have the KA24e in my truck. It has the V6. But, I've seen several posts about people doing this.

There should be a spring behind the chain guides that keeps tension on the chain. You might want to check that it is in there.

Here is my favorite write-up on the timing chain for the KA24e because of all the pictures he took. He did all of it, but you can skip to the part that means something to you:





__





Timing Chain replacement on KA24E - Infamous Nissan - Hardbody / Frontier Forums


Timing Chain replacement on KA24E Engine and Drivetrain



www.infamousnissan.com





Now I want to address the part where you removed all of the emissions. Your 1996 is an OBD2 vehicle. If it doesn't see the readings from the emissions sensors, it will always run in limp mode. But, you don't need to worry about that until you get the timing chain issue resolved.


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## LowkeySebs (12 mo ago)

jp2code said:


> Let me start by saying that I don't have the KA24e in my truck. It has the V6. But, I've seen several posts about people doing this.
> 
> There should be a spring behind the chain guides that keeps tension on the chain. You might want to check that it is in there.
> 
> ...


*
I checked the guide and honestly, I didn't really see a spring. All I saw was the guide plated to the metal backing on the timing guide. Could it be that I got a faulty guide and needs to be replaced? I looked up the link you gave me which I very much appreciate by the way! But I did that as is already step by step and had this as my outcome still so quite frankly I'm not quite sure as to why it's skipping teeth still.

As for the emissions, yes, it is a OB2 so deleting the emissions will probably put it in limp mode but I bought a 89 240sx ECU, would installing that get rid of the limp mode? *


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## jp2code (Jun 2, 2011)

The spring is shown in the schematic above. Do you see it? Passengers side, about the middle. 

If you are using the 89 ECU from a 240, you won't need to worry about OBD2 anymore. That ECU isn't OBD2.


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## rogoman (Dec 16, 2004)

LowkeySebs said:


> *I checked the guide and honestly, I didn't really see a spring. All I saw was the guide plated to the metal backing on the timing guide. Could it be that I got a faulty guide and needs to be replaced? I looked up the link you gave me which I very much appreciate by the way! But I did that as is already step by step and had this as my outcome still so quite frankly I'm not quite sure as to why it's skipping teeth still.
> 
> As for the emissions, yes, it is a OB2 so deleting the emissions will probably put it in limp mode but I bought a 89 240sx ECU, would installing that get rid of the limp mode? *


If the chain tensioner does not have a shoe retainer (early KA24DE engines), it must be locked by inserting a locking pin made from a piece of wire that fits in the pin hole on the front of the tensioner. The shoe may pop out and have to be reinserted if this is not done.


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## Harri1 (12 mo ago)

jp2code said:


> Let me start by saying that I don't have the KA24e in my truck. It has the V6. But, I've seen several posts about people doing this.
> 
> There should be a spring behind the chain guides that keeps tension on the chain. You might want to check that it is in there.
> 
> ...


Is it safe to work in limp mode?


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## jp2code (Jun 2, 2011)

Harri1 said:


> Is it safe to work in limp mode?


Yes. It is mostly emissions-related when you are in limp mode, so your engine will be more polluting and less fuel-efficient, but it will not hurt the engine.


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## LowkeySebs (12 mo ago)

jp2code said:


> The spring is shown in the schematic above. Do you see it? Passengers side, about the middle.
> 
> If you are using the 89 ECU from a 240, you won't need to worry about OBD2 anymore. That ECU isn't OBD2.


Ohhhh the spring you’re referring to the spring inside the tensioner? Yes the spring is in there, saw it myself when I ordered it from Nissan and I put it in bucket of oil so it gets pressure since it’s hydraulic. There is 0 slack on the passenger side where the tensioner pushes out, it’s always firm no matter how many times you rotate the motor. The issue is on the other side on the driver side, that’s where it’s completely loose and skip around two teeth per half rotation. I’ve tried everything to get the slack out but I haven’t found any method that works. Also perfect, I was worried the motor wouldn’t run correctly due to emissions and sensors not being plugged in. Good to know the ECU will take care of that.


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## jp2code (Jun 2, 2011)

Something sounds off. The side with the tensioner should take up the slack in the chain.

I see pictures showing a link that marks a starting point on the crankshaft sprocket. If you have the link lined up and you still have slack, try turning the chain around. Maybe it is on backwards. 

I don't know. I have the V6.


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## LowkeySebs (12 mo ago)

jp2code said:


> Something sounds off. The side with the tensioner should take up the slack in the chain.
> 
> I see pictures showing a link that marks a starting point on the crankshaft sprocket. If you have the link lined up and you still have slack, try turning the chain around. Maybe it is on backwards.
> 
> I don't know. I have the V6.


Something is definitely off but I’m not understanding what exactly because I put the chain to the marking on the cam sprocket and crank sprocket correctly along with at top dead center then pull the pin on the tensioner but it just doesn’t fix the issue. It gets super stiff on both sides then for some reason it gets super loose like a soft spot then it skips the chain and after it does skip it gets stiff once more and repeats. At this point I’m chasing my tail because I have no idea what exactly is wrong with it anymore. Chain isn’t backwards either, I made sure of that. When I get home I’ll send some pictures


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## jp2code (Jun 2, 2011)

Something comes to mind: I _think_ that tensioner is activated by oil pressure. So when the engine isn't running, the tensioner is not pressing the slack out of the chain.

In the installation instructions, does it mention anywhere about applying extra tension on the "tensioner side" (like with a chock-block or a prybar) until the rest of the assembly is put together?

You might also want to search YouTube for some videos of people installing the chain on the KA engine. It's a popular engine, so I'm sure there are thousands out there. Maybe watching a video will allow you to see something that you didn't catch during your install.


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## VStar650CL (Nov 12, 2020)

I'm no KA expert, but the tensioner is definitely hydraulic with a preloading spring. Some new ones come compressed with a "grenade pin" holding the plunger back, you pull the pin to allow the spring to load the plunger once the chain is lined up. None of the preloading springs exert very much tension, so it's always a good idea to disable fuel and "dry crank" the engine for about 30 seconds to pump-up hydraulic pressure before allowing it to start. That will preclude the chain from jumping teeth when the crank first accelerates it.


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## gannawaydogma1 (2 mo ago)

I am having that same issue currently but it jumps timing as I drive. 96 nissan with a KA24e


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## jp2code (Jun 2, 2011)

gannawaydogma1 said:


> I am having that same issue currently but it jumps timing as I drive. 96 nissan with a KA24e


Sounds like your timing chain is loose. You need to get a timing chain kit with new guides and a new tensioner.


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## jimcasada (9 mo ago)

One of the long side chain guides was broken on my 1996 KA24E D21. It wasn't jumping time, but it would make a lot of noise whenever you first started it up. Below is the kit I used about a year ago (it was $69 back then). It includes a new water pump and oil pump too, and everything fit perfectly. I would suggest changing all that stuff out, since you'll have to have it all opened up anyway.








Timing Chain Kit Water Pump Oil Pump for 89-97 Nissan 240SX D21 Pickup KA24E | eBay


Find many great new & used options and get the best deals for Timing Chain Kit Water Pump Oil Pump for 89-97 Nissan 240SX D21 Pickup KA24E at the best online prices at eBay! Free shipping for many products!



www.ebay.com


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## racerbob911 (1 mo ago)

The links that are marked on the new chain will only line up once when you install the kit. They will align again after so many rotations of the crank. That is not meant as a way of checking cam timing because there is no way you can accurately predict when they will line up in the original, installed positions again.

As to the tight spot during manual rotation, maybe there is a tight guide or valve spring interference of some sort. Rotate the engine by hand till you reach the tight spot and check to see which valves are moving to their highest opening position. You will need to resolve any physical binding before starting that engine. It could be almost anything, but look at the things that likely changed when you did the valve job. 

Did you have any machine work done by a shop? Did you pull the pistons and change rings or rod bearings? You can connect an external pressure oiler (using compressed air as power source) and pressurize the tensioner to see if that tight spot goes away with good tension on the moveable chain guide. It most likely won't change anything, from my experience.


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