# Intermittent timing chain rattle



## fsglover (Jan 14, 2011)

I have a 93 hardbody with the KA24E with about 276K on it. Every once in a while if the truck has been run for a while and restarted the timing chain will rattle like hell for a few seconds and then quit. It only does this when the engine is hot. The oil light stays on longer when hot also. I realize that the engine has alot of miles but would it be worth replacing the oil pump or tensioner (i think it works off oil pressure). I also realize that i can buy an engine with 150k for about $350. I only paid $1300 two years ago and it has never given me a problem. Just thought I would see if anyone had a thought/ Thanks


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## SPEEDO (Jun 9, 2003)

when was the last time the tensioner, chain etc was replaced?


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## fsglover (Jan 14, 2011)

To my knowledge is it original. The previous owner had a detailed maintenance book. My first opinion was to replace all the timing chain components because of the mileage but it does not make the noise very often. I figured replacing the oil pump was a band-aid but just wanted some advice. Thanks


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## rogoman (Dec 16, 2004)

If the oil pressure idiot light comes on at all, you most likely have low oil pressure which could be caused by several factors. Worn rod/main bearings. Plugged up oil filter. Dirty oil pickup. Most of the time it's the oil pump which may be worn and not producing the proper oil pressure/volume.

You can check the pressure very easily by installing a temporary mechanical oil pressure gauge. You would remove the oil sensor which is located next to the oil filter and install the mechanical oil pressure gauge in it's place; you may need to get an 1/8 BSPT to 1/8 NPT adapter to hook up the gauge.

With the engine fully warmed up, the pressure should be as follows:
idle - at least 11 psi
3000 RPM - 60 to 70 psi

If the oil pump needs to be replaced, it's easy to do so as it bolts on externally.


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## fsglover (Jan 14, 2011)

I appreciate the feedback. I will try to check it out this week or weekend and reply back for the sake of others. There is absolutely no timing chain noise any other time except for the startup sometimes when the light stays on longer and i guess the tensioner does not function properly. I know there are alot of these trucks with a lot of miles on them. Mine is a daily driver.


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## Grug (Aug 20, 2009)

Hey fsglover. My '97, 2.4 has the same symptom. Sometimes I get no rattle on cold starts and other times I get the worst rattle on warm starts. All the research I did suggested the rattle should only be occurring on cold start-ups...after the tensioner has lost it's pressure. So, I would be inclined to think your problem is not necessarily tensioner related. Might in fact be your oil pump (or a related component). Do you use good oil filters (Nissan, Wix...)? 

However, that's a lotta' miles on your beast. Might be time for a timing chain job anyway...if you plan on keeping the truck for a long time.


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## fsglover (Jan 14, 2011)

I am just trying to keep this bad boy running good for the time being - which it does except for those time it rattles. I believe it is the oil pump also. It never rattles at cold startup only when it is hot and the oil is thin i guess. I know alot of people think Lucas is snake oil and i kind of agree. would it be of any help to the viscosity at startup? My buddy i work with used lucas every oil change but used the cheapest Sams oil he could get and never turned a bolt on his 93 hardbody and sold it for $1700 with 341,000 miles.


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## Grug (Aug 20, 2009)

I don't have any experience with Lucas...sorry. I had a '93 HB with the 2.4 and it was the same as your buddy's. The engine never had a problem. My '97 however has the rattle and I keep saying I'm gonna' fix it, but haven't got to it yet.

I run conventional 5W30 in my truck. Used to run 100% synthetic in my '93.

I'm not trying to pass along advice, but I've read that some guys just live with the rattle on start-up...for years. It's when the rattle persists after start-up that you need to be concerned...or so I've read (not speaking from experience).

Good luck, man.


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## azaware (Aug 25, 2011)

You might try a compression test to get an idea if the eng is worth messin with.


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