ev13wt

Here is a pic. You want to move in with the long screwdriver, close to the chain above the guide.
A pic for reference from https://www.pirate4x4.com/forum/toyo...m-misfire.html

Mason Edmison

I used the ITM HD (with metal guides) kit from rock auto(https://www.rockauto.com/en/moreinfo...278042&jsn=437). When I pulled the vc before, the chain seemed good and tight but I'll take a look again.

ev13wt

I am terribly confused. Could you adjust all valves (half at tdc number 1, next half after one rotation of the crank) or just the ones from the number 1 piston?

Are they all adjusted?

Mason Edmison

yep. FSM http://htftp.offroadsz.com/marinhake...nce/2maint.pdf

Under hot engine operations...

So pulled the vc to take another look at things nothing too out of the ordinary but I did notice more marks on the camshaft (see video). Not sure if that would cause this sound or not.

Also pulled each spark plug and revved it up a bit. No change. This sucks - at this point I just wish it were something obvious so I knew for sure.

I do hear a rattling from the timing chain cover but I also hear distinct sounds from the VC area just as loud.

On cold start, when I first turn the truck on I hear a real brief timing chain rattle then it goes away (like within a second).

video :

ev13wt

Chain tension looks fine from here. Kinda running out of ideas here too.

Remove belts. Start it up for 10 seconds. Takes all accessories out of the equation.

Reattach belts and swear at it.

ev13wt

You could always run it hard till something breaks, then you will know what it is.
In typical Toyota fashion, it will be fine, then it will go away. Or something will happen.

A side tip, in a bigger job mark each bolt you torqued down with a tiny dab of paint. Keeps you sane.

Another idea is: sure the chain guides are down tight? Forget a bolt?

Co_94_PU

iTrader: (-1)

I expect if you drain the oil, do so into a very clean pan incase it is reusable, you are going to find metal. In if so you should pull the pan and reinspect the bottom end.

The spring tensioning the rocker arm, while it may not be its primary purpose, allows you to use your inspection mirror to check the wear pattern. This pattern is best if it is mirror like, even side edge to edge and doesn't reach the trailing edge indicating it's lost its bevel. If it's worn to the trailing edge they need replaced. If it's pointy to one side or the other it needs replaced. If it's gouged or has stripes, it needs replaced. If you have to replace a rocker the cam needs checked.

EW, oil and water most certainly mix. This is the milky honey looking stuff you'll find under your oil fill cap due to the PCV system sucking moist air thru the intake, it's normal here it forms.due to the cap cooling and causing condensation of the oil and water vapors. The PG in antifreeze may actually accelerate this and act as a homogenizer, like acid (lemon or vinegar) when making mayonnaise. Ever seen the white stuff they use when machining aluminium, that is an oil and water mixture, it keeps the bit cool and the chips from sticking, but it has very little suspension characteristics good for machining bad for keeping two parts from touching.

Mason Edmison

I did find strip like marks and itty bitty scratch marks (could just barely feel with my finger nail) on my cam but I did not think to use an inspection mirror to check the rockers. I will have to do that.

snippits

My 92 22RE was doing the exact same thing on cold start, but no rattling after that.

Head gasket was bad, so I installed a new timing kit too. No start up rattle with the new chain kit, but I did use a new Enginetech complete cylinder head. Just bolt it on and go.

Did you have cylinder head milled, or do you know if the cylinder head has been milled?

When I installed the timing kit with new cylinder head, it was a pain in the ass to get the cam sprocket on. It was a very tight fit. No more rattle on cold start, and new timing kit was installed 16 months ago.

Mason Edmison

yeah took the head to the machine shop where it was pressure tested, machined, and new valve seals installed. I used the LCE engineering trick to get the cam on. Apply upward pressure to the cam with screwdriver while rocking the crank back and forth.

Co_94_PU

iTrader: (-1)

This maybe metal bypassing the oil filter, it maybe from dry start ups (oil film runs off the cam lobes). Dry start wear is increased by not having an anti drain back style filter (it should have a rubber gasket you will see when you look into the openings).

Since you have a new timing set, with a new tensioner I'll assume, you either don't have the proper filter or its running out the crank bearings. So I would count that as another sign (strike) on pulling the pan back off.

Compressing my tensioner takes my biggest pry bar and a few swear words, sometimes.a blood sacrifice.

Mason Edmison

If it were the crank bearings wouldn't the noise have gone away when I pulled the spark plug or quieted down? There was no effect when pulling the plug wires.

er yeah I guess I dont mean when you say running out the crank bearings. I adjusted the valves COLD at 007 and 011. It seemed to help a little but I might be making that up.

By pulling the pan, I would essentially be yanking and feeling for play, yeah?

ev13wt

^^ In theory, yes.

I still think the tensioner is stuck "inside". Chain tension is great, new, hard to place on camshaft.
Try it with a really long flathead screwdriver.
(edit: I have had this issue)

Co_94_PU

iTrader: (-1)

I find it the most odd that your loudest noise location is on the valve cover bolt/nut. There is a lot of odd geometry there for sound to travel along..

What did the cover under side look like, no indication of contact? If you dab grease on the tappet ends does it transfer to the cover?

Any noticeable wear on the chain guides that would indicate maybe the tensioner isn't functioning as it should?

With the pan removed.. Yes you would do a feel test, if it made any sort of clacking or notable movement it's bad. You would also want to do visual inspection, do the rods look straight, if you rotate the engine over are there clearances between the crank and piston lobes.

How certain are you of the timing cover bolts, there is atleast one I know you can put in the wrong place and have contact issues there.

Mason Edmison

Yeah, this is extremely aggravating. I bet I have stood around with a stethoscope for a total of 5 hours and nothing.

Inside of valve cover looked fine. Did not look like there was any contact with anything.

Couldn't tell of any odd wear on timing guides. I used the old timing cover as a 'template' as to not mix anything up. Seems like it is really loud coming from the oil pump area?

Again no change when I pull plug wires (one by one).

I did notice something strange this evening. It doesn't seem to do it when it's cold. I can't tell if the fan drowns it out or what but it does not make the chatter/rattle/ knock (whatever you want to call it) right away.

What could this mean?

Mason Edmison

another update:

removed both belts and ran it (briefly) - noise still there.

Also took a long screw driver and depressed the tensioner a few times in case it was stuck (oil pump bolt is not obstructing tensioner). Noise still there.

I really thought I had found it as one of my exhaust manifold studs loose but upon tightening it down the noise is still there.

It definitely does not do it right on start up. For the first minute or two I rev it up and it sounds fine. After that it starts rattling. Also - seems like I am getting oil pressure up top, i.e. even with the cover loose it's peeing oil out all over.

could this all be then tensioner not getting enough oil pressure (dirty ports)? Wouldn't the oil pressure be higher on startup than when it warms up accounting for it being fine for the first few minutes of running?

I don't know. I am really pulling my hair out. any ideas?

Mason Edmison

bump bump

Co_94_PU

iTrader: (-1)

You could be sucking up debris into oil pump pick up. This would cause the pressure to drop, then the bits drop after its shut off. A semi obstructed oil galley could have the same behavior.

​​​​put an analog guage on it and check the pressure.

Did you ever inspect the oil for particles?

RJR

You could have a cracked exhaust manifold that only leaks when it gets hot and expands. Some exhaust leaks can sound very "mechanical" in nature. Get a piece of rubber hose about 3 feet long and use it to listen to various points around the exhaust system.

Mason Edmison

I see. Cool - i'll pick up a oil pressure tester gauge.

Did not drain the oil yet and check for particles, though I am quite sure I will find some as there is still probably bits from the chewed up timing guide.

Going to spend some time with it this weekend. I'm thinking I may be pulling the pan and/or timing cover to inspect at this point.

Any quick and dirties to clear out possible gunky oil galleys? sea foam?