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Discussion Starter · #1 ·
ok. i dont know if you guys know but when the KA24de is low on oil the lifters and cam start to make a rattling noise. well mine is making that noise, kinda sounds like the chain rattling.

anyway, i check the oil its full, i check the oil pressure and is normal, i pull the valve cover off hoping that none of the shims or lifters has come out and are floating the motor and nothing. I checked all the bolts to see if any where loose yet again normal. I checked the timing chain and guides to see if they where loose and you guessed it NOTHING.

Any ideas on what might be making this thing rattle? the only thing i can think of that i cant test at the moment is that after the motor rebuild the valves have just set into place and the clearence on the shims is off. but i cant check it right now cause i dont have my feeler guage.

If anyone can scratch there heads and com up with something Please let me know cause i cant thinkof anything. the car is parked untill i figure it out cause i dont want to cause any more damage then might allready be done. and i need the car ASAP so if you can help i would apreciate it.

the car is NA btw
 

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i know alot of KA's have the timing chain rattle, the lower tensioners crap out
 

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9sec240 said:
The KA doesnt have lifters.

WRONG!

then why does it have a big ass sticker under the hood that shows you valve lash specs for adjusting the solid lifters?

and i wonder what that magical space that is inbetween the camshaft lobe and the valve? magic valve mover uper/downers i guess. or maybe my FSM wrong.

but I guess you want proof...
 

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Discussion Starter · #6 ·
LOL damn

BTW everything is new except: oil pump, valves, lifters, some of the shims, springs, and power stearing pump. lol everything else is BRand new with like 10k miles on it. no forged pistons, yes i still have the guides but it is WAY to loud for that. and yes the valve clearence was set in rebuild.
 

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240°Heat said:
LOL damn

BTW everything is new except: oil pump, valves, lifters, some of the shims, springs, and power stearing pump. lol everything else is BRand new with like 10k miles on it. no forged pistons, yes i still have the guides but it is WAY to loud for that. and yes the valve clearence was set in rebuild.
i was gunna say check the valve clearence or at least double check it.
 

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Fidelity lol i wish i woulda saw this one earlier. but your answer is great!

also you all have listed everything to check i think. I'll just list some other crazy stuff that can make noises , heat shields injectors ticking, stuff hitting the steering rack, butterfly valves getting ready to grenade your engine :) just the usual stuff. goodluck though, let us know what it is.
 

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Discussion Starter · #9 ·
i checked the valve clearence and some of them are way off but only on the "too much clearence" side. i think one of them is .021 which is about .006 to much. the funny thing is that they were all in clearence when the motor was done. and i think some of the valves are not closing all the way cause when i rotate it by hand with the plugs still in it it is easy and i can hear air leaking out. GOD i hope the valves arent bent
 

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uno said:
Fidelity lol i wish i woulda saw this one earlier. but your answer is great!

also you all have listed everything to check i think. I'll just list some other crazy stuff that can make noises , heat shields injectors ticking, stuff hitting the steering rack, butterfly valves getting ready to grenade your engine :) just the usual stuff. goodluck though, let us know what it is.
I was in a bad mood an I had too much time on my hands, you never know what that will equate. lol


yeah I had a crazy ratling noise for the EGR pipe, the bracket kept wacking my heatshield, some plies and a bit of force, the bitch still wobbles with engine movement but it doesnt hit the exhaust heat shield.

and you would know if the valves were bent.
 

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Discussion Starter · #11 ·
a friend of mine told be that when i was at the track that it might have floated a valve due to using the old 130k mile springs and that it could have taped them a lil but hardly at all. all i know is that some of the vavles are open slighty. but the non of the clearences are to tight which would cause them to be sticking open. so it would have to be a very slightly bent valve.

the car runs with no problems other then a rattle. so if they are bent it cant be to bad at all. this might also explain the lowering in power as of late. but it hasnt been much.
 

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if you float a valve, your just lacking oil pressure in the cylinder head area of the valves. so drive it around for a bit and it should quiet down after a solid 20 minute drive.

OR it could be a valve guide clearance issue or try a different weight oil it may be too thick for the clearance and its not getting up to the rest of the head.

if we had hydraulic lifters, i'd say just replace the fuckers for like 15 bucks, you probably got a bad ball check valve or more, but thats not the case.
 

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Discussion Starter · #13 ·
i htink its the clearence and the possibly soft springs. either way i dont know what i will do yet. but i do have some ideas.

the things i know for FACT:

the springs have 130+miles

the clearence on the valves that are out of clearence are WAY out of clearence

the vlaves leak when i rotate the motor with the spark plugs still installed




all this looks like either bent valves or just spft springs.
 

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Fidelity101 said:
WRONG!

then why does it have a big ass sticker under the hood that shows you valve lash specs for adjusting the solid lifters?

and i wonder what that magical space that is inbetween the camshaft lobe and the valve? magic valve mover uper/downers i guess. or maybe my FSM wrong.

but I guess you want proof...
Wow.. that was kind of rude...

The KA doesnt have what you would normally refer to as a "lifter" and I assumed what the original poster was asking was if the KA would make noise if the oil pressure was not up enough to pump up a hydrolic lifter ie push rod motors... I mearly stated that the valvetrain doesnt need oil pressure to take up slack in the valve clearance...

Your FSM may call it a lifter, but its actually known as a cam bucket... That diagram also calls the cam cover a "rocker cover" and there are CLEARLY no rocker arms in the KA motor.. Maybe something went wrong with the translation from Japaneese to English...

People call the 4G63 hydrolic lash compensators "lifters" all the time and "lifter tick" is quite comon on older DSMs... When I answered his question, I was mearly stating that this is NOT the case in a KA motor...

Have a nice day...
 
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