skinnadoor

Hey everyone...


We adjusted the engine valve clearances, 4 intake, and 4 exhuast valves. I think we may have adjusted them too much instead of .008 it may be .010 and same for exhuast, .012 but we may have put them larger, around .014......


My friend said loose valves, "Through adjustment" can cause the rocker arms to be loose and knock like it is in the video.....

Can anyone confirm this for me,? i'm ajusting them in the morning, "Tighter" to try and stop the knocking diesil sound. Truck is fine though, runs wicked, better accelleration since the adjustment, just this knocking,

heres the video... remember, loose valves..... sounding like this.... would love to hear from someone that did the same thing then corrected it.

Video .....

http://www.youtube.com/watch?v=AoHv9H5WBTY

[YOUTUBE]AoHv9H5WBTY[/YOUTUBE]

foot0069

Wow! I'd check the valves, could be loose. Did you have the exhaust off? Possible leak? Maybe one of the water pump bolts in the wrong place hitting something? Pull the cover and have a good look see.
Jim

skinnadoor

Your right man, it looks like the valves... being loose....

foot0069

Yeah saw that you said that but thought I had one right a while ago and it sounded scary as well, even made me think I had shaved the head to far and was getting piston knocking the top. But it was loose valves. I,d open that thing back up and take a look.

Four Runner

Do you have the oil baffle, above the rockers on that engine??

1. There's an older TSB about using caution when filling the oil, and the possibility of slightly bending the oil baffle. The baffle contacts the rocker, making a similar noise. The niose gets transmitted through the baffle/bolts/head. (Kinda like knocking on a long 2x4 and hearing it at the other end.)

*Pull your cover, and see if the baffle is getting contacted.

2. Also, did you do your valves with it cold or hot?? That's also a possibility.

Run it 'til warm and check the valve clearance.

3. New Chain, Older Gears/Etc?

*Things take a bit to bed in.

skinnadoor

The chain and kit, are all new. My buddy that did the job was thinking it's the rocker arms, but he's not sure. I'm not sure about the oil baffle or not......... A new oil pump and water pump were installed too.

Don't get me wrong, the truck works fricken wicked...... faster accelleration.. after this sound showed up, he double checked the valve clearance, he did it both hot and cold, by the book, with my manual.

Hey maybe your right and it just needs the kinks worked out, as soon as you give her any gass at all, the sound is gone. Engine sounds sweet all the way up to 65mph. Idleing at 750rpm when she's warm.

It's comming from somwhere at the front, below the valve cover, but above the timing chain cover....

I'm trying not to stress over this.... but the sound wasn't there before the job..... perhaps it was, but just softer sounding.....

skinnadoor

Ok , an update.

I just took it over a co-workers hous, Ex Gm mechanic. He said for certain, that it's the valves, Too loose. My buddy adjusted them, but he adjusted them too loose. 8 thou for intake valves, 12 thou for the exhast is what they should be.

In short, The rocker arms are not tight enough causeing her to sound like a diesil.

Tommorow we are adjusting them, i will for sure post a video of the results of the valve adjustment.

drews4rnnr

Let me know how you make out . I did the same job & mine is a little quiter than your . I adjusted the valves 4 times if I remember right .

foot0069

Remember it,s a fine line to tight and you'll burn a valve, be sure the engine is warm thermostat has to be open.
Jim

skinnadoor

Ok... we popped off the valve cover again, and double checked all the valves... all of which are right on the money, .008 for intatke and .012 for exhaust. This has me stumped. Still. The oil pump and water pump were also changed in this job, we have ruled out the timing chain, everything looks good.


Are intial valve clearances before we touched anything were too tight, that is, the exhuast side valves were all to tight, .012 feeler wouldn't even go in.

It's after our adjustment of these tight ass valves that the noise started..... But puttin them in spec should be a good thing. the cam shaft and rocker arms, lobes, are all in great shape.

1 more important thing ........ When the truck was dead cold, there was no noise, only after 2 min of warming up, did this sound re-appear...

Thoughts?

TORTIS

iTrader: (1)

The plot thickens. I can't wait to see what gremlin is living in your motor.

drew303

distributor gear?

you said its coming from the distributor. pull it and check it out? retime it.

kahn

Ive seen something similer on one of these engines. sounds like low oil pressure. you said you replaced the oil pump? is that when it started? also, if I am not misstaken, the timing chain tenssioner runs on oil pressure, and thats what they sound like with no tenssion. also I beleve said tenssioner is behind the T-cover right below the distributer.
well a cupple of ideas anyway, hope you get it figured out.

mr toytech

how tight are you torguing the valve cover nuts? if you overtighten them it can sound like that. with it running loosen them until the noise stops but dont leak.

skinnadoor

Can you start the engine with the valve cover off?????? is that what you mean?

ovrrdrive

If you overtighten the valve cover nuts the rockers can hit on the valvecover. That's what he's referring to.

I don't think that's your problem though as your noise is near the distributor.

And no, don't try to start the engine with the valve cover off unless you want an oil bath. We did that once to locate a noise and it probably slung a quart of oil off the timing chain in 2 seconds.

Still no luck on this problem?

skinnadoor

VALVE COVER NUTS.... !!!! I haven't tried that....... looseing the valve cover. it's worth a shot though. I had a huge brainfart there.

If the valve cover is overtightend, does it give off that diesil sound???? i'm giving it a shot righ now...

skinnadoor

Well, i did what you guy's said... i backed off the valve cover bolts, and sure enough , the sound started to go away, the nuts were torqued so much the rubber bushings were sqwished almost flat.

So after backing them off... and letting it run a bit, the sound dissapeared.
When i restarted the 4Runner, the sound was there, but quickly went away.

As well, when i would be pulling up to a stop, before i would hear the disiel sound like in the video, now i can barely hear it.

How tight do i have to have the valve cover???? i backed off the bolts, and just brought them so they were just snugg.

Let me know and thank you so much for the good tip you guys.... My engine sounds nothing like the video now... very quiet.

I still hear the knocking a touch after start up, so perhaps the cover is still a bit too tight.

My thanks to Mr. Toyota and Overdrive. After all the work, timing chain kit, oil pump, water pump, valve adjustment..... the horible noise was comming from the damn valve cover being too tight... i can't help but feel a little baked....