Two part question 2008 Toyota Landcruiser. Strange noise at first start up of the day & low coolant levels (hopefully reservoir will remain full now).

[BondJamesBond]

I’ve got a newly purchased 2008 Toyota Landcruiser with 160,000 miles and a strange noise on start up, goes away after probably less than a minute. From what I can tell it’s coming from the front of the engine area around the pulleys.. It’s a somewhat light sounding but fast rattle/ticking noise then it’s gone. Oil levels and pressure are good. It doesn’t happen every time I start it, but usually at first start up of the day. Temps haven’t been cold, and I’ve only owned it less than a week. Previous owner says he’s never heard that sound before. I tried posting a video but don’t know how to or if I even can here.

Also when I bought it, the coolant reservoir was very low, I filled it that same day and a couple days after our 400 mile trip home I checked and it was empty again. I’ve refilled in again and it seems to be staying full. Engine temp is right in the lower middle position. The radiator and water pump were both replaced in 2017.

 

[BondJamesBond]

So I went to start it this morning and battery was dead. It’s a fairly new battery, so I’m thinking the sound I was hearing may have been the alternator and it may have finally but the dust. I jump started it and the lights came on and systems were coming all on in the engine (I have no idea which ones), threw a bunch of codes because I tried starting it with low voltage I think. Any thoughts?

 

[Rigger]

Moved to 200 section.

 

[zoned]

The sound you are hearing is tensioner noise. Mine used to do it until I switched to 5w-30 oil.
Search the forum for it and you’ll find a couple of different ways people have cured it.
Search valley plate leak for the missing coolant.
Look for pink residue on the front and back of the engine.depending on the severity it may be a need to fix now or later thing. If you say it’s not leaking after you filled it, it could have just been poor maintenance from the previous owner I’m not checking it since the radiator replacement.

 

[bloc]

What is the voltmeter on the dash saying once it is running? That should indicate a bad alternator. I will say unless it was fouled with mud it is unlikely to go bad so soon.. these things usually last a very long time.

The rattling can be the cam chain tensioners, but that is usually quite loud.

This explains the issue, though I’m not sure I agree with 100k limit on chains. Many 5.7s are on the road with multiples of that mileage doing just fine.

 

[BondJamesBond]

The sound you are hearing is tensioner noise. Mine used to do it until I switched to 5w-30 oil.
Search the forum for it and you’ll find a couple of different ways people have cured it.
Search valley plate leak for the missing coolant.
Look for pink residue on the front and back of the engine.depending on the severity it may be a need to fix now or later thing. If you say it’s not leaking after you filled it, it could have just been poor maintenance from the previous owner I’m not checking it since the radiator replacement.

Thanks for the useful information man, much appreciated!

 

[linuxgod]

What is the voltmeter on the dash saying once it is running? That should indicate a bad alternator. I will say unless it was fouled with mud it is unlikely to go bad so soon.. these things usually last a very long time.

The rattling can be the cam chain tensioners, but that is usually quite loud.

This explains the issue, though I’m not sure I agree with 100k limit on chains. Many 5.7s are on the road with multiples of that mileage doing just fine.

I'm not 100% clear on how the tensioner works but I'm assuming it only goes in one direction (tighter, as the chain slowly stretches over time). If that's the case then I'm also assuming the wear on the teeth is what happens as the chain slowly stretches and the tensioner is working it's way up to the next tooth? One last assumption is that all chains will stretch and the stretching isn't necessarily a problem so long as you can keep tension on them... thus if your tensioner teeth aren't "mostly worn" then no need to replace the chain until the tensioner is fully extended (though admittedly "once you're in there" it's not a very expensive part).

Ok now that I've probably incorrectly explained how this doesn't actually work, it'd be cool if someone with deeper knowledge could explain that.

 

[linuxgod]

FYI low coolant could be air in the system, particularly if the PO had any cooling system work done and the mechanic didn't "burp" the system sufficiently. Top it off a few times and see if it eventually settles between the L/H marks on the expansion tank or if you need to keep adding coolant after several days.

 

[bloc]

I'm not 100% clear on how the tensioner works but I'm assuming it only goes in one direction (tighter, as the chain slowly stretches over time). If that's the case then I'm also assuming the wear on the teeth is what happens as the chain slowly stretches and the tensioner is working it's way up to the next tooth? One last assumption is that all chains will stretch and the stretching isn't necessarily a problem so long as you can keep tension on them... thus if your tensioner teeth aren't "mostly worn" then no need to replace the chain until the tensioner is fully extended (though admittedly "once you're in there" it's not a very expensive part).

Ok now that I've probably incorrectly explained how this doesn't actually work, it'd be cool if someone with deeper knowledge could explain that.

There are instances where when you shut the engine down the cam lobes working against the valve springs will try to turn the cams slightly past their intended indexing and this puts tension on the non-drive side of the chain. But without the engine running the hydraulic part of the tensioner doesn’t hold tension. So the ratcheting pawl system takes over, keeping too much slack from developing.

If those teeth flatten out, the tensioner can retract in the above condition, and when you go to start the engine the chain can slap around like crazy until it builds oil pressure and that protrudes the tensioner. In extreme cases like mentioned in the video it can make the cam or crank jump a tooth.

Plus it is easy to find videos of tundras with ongoing chain slap well after oil pressure is built, though not nearly as intense as before.. so I’m not sure what is going on there.

Yes it is more of an issue on an engine with stretched chains, but technically even a new engine has the tensioners extended some. It’s just that even if the pawl doesn’t work there isn’t enough slack in the chain yet to let it jump a tooth.

 

[BondJamesBond]

I'm not 100% clear on how the tensioner works but I'm assuming it only goes in one direction (tighter, as the chain slowly stretches over time). If that's the case then I'm also assuming the wear on the teeth is what happens as the chain slowly stretches and the tensioner is working it's way up to the next tooth? One last assumption is that all chains will stretch and the stretching isn't necessarily a problem so long as you can keep tension on them... thus if your tensioner teeth aren't "mostly worn" then no need to replace the chain until the tensioner is fully extended (though admittedly "once you're in there" it's not a very expensive part).

Ok now that I've probably incorrectly explained how this doesn't actually work, it'd be cool if someone with deeper knowledge could explain that.

 

[BondJamesBond]

Great explanation man! Seems to make sense to me, I appreciate the time and effort you put into explaining that one. Now if someone has better info than that I’d be super happy to hear anything further on the subject. All and all it’s a pretty amazing rig that I’m thoroughly enjoying. It’s got a nice set of 2.5 inch Dobinson MRA suspension with added upper control arms too! Thanks for the reply.

 

[bloc]

I forgot to mention toyota apparently updated the tensioners so there may be a real fix for the problem. But as you see in the video, getting in there is quite involved.

I have 170k on mine and have had maybe a half dozen instances of chain slap, but since switching to 5w-30 over a year ago it hasn’t happened once. Which is ironic because that should slow down oil pressure build on start.. but I wonder if the thicker oil prevents the tensioners from retracting in the first place.

 

[BondJamesBond]

I forgot to mention toyota apparently updated the tensioners so there may be a real fix for the problem. But as you see in the video, getting in there is quite involved.

I have 170k on mine and have had maybe a half dozen instances of chain slap, but since switching to 5w-30 over a year ago it hasn’t happened once. Which is ironic because that should slow down oil pressure build on start.. but I wonder if the thicker oil prevents the tensioners from retracting in the first place.

Possibly? I guess I’ll give the thicker oil a try next.

 

[bloc]

Possibly? I guess I’ll give the thicker oil a try next.

It was specified in other markets in this engine so should be perfectly safe, just stick with a synthetic as the manual requests. Lots of people here and on tundra forums have had good luck with it. Quiets down the harmless but noisy valve train noise nicely as well.

Definitely worth a look vs tearing into the engine.

 

[BondJamesBond]

It was specified in other markets in this engine so should be perfectly safe, just stick with a synthetic as the manual requests. Lots of people here and on tundra forums have had good luck with it. Quiets down the harmless but noisy valve train noise nicely as well.

Definitely worth a look vs tearing into the engine.

Yes definitely! I’ve used a

I'm not 100% clear on how the tensioner works but I'm assuming it only goes in one direction (tighter, as the chain slowly stretches over time). If that's the case then I'm also assuming the wear on the teeth is what happens as the chain slowly stretches and the tensioner is working it's way up to the next tooth? One last assumption is that all chains will stretch and the stretching isn't necessarily a problem so long as you can keep tension on them... thus if your tensioner teeth aren't "mostly worn" then no need to replace the chain until the tensioner is fully extended (though admittedly "once you're in there" it's not a very expensive part).

Ok now that I've probably incorrectly explained how this doesn't actually work, it'd be cool if someone with deeper knowledge could explain that.

Oh, to answer your question about the voltage meter.. The alternator test we did was good, battery checks out too. We narrowed it down to the #1 possible cause being corrosion on the battery terminal causing a poor connection. Fingers crossed. Lol

 

[BondJamesBond]

It was specified in other markets in this engine so should be perfectly safe, just stick with a synthetic as the manual requests. Lots of people here and on tundra forums have had good luck with it. Quiets down the harmless but noisy valve train noise nicely as well.

Definitely worth a look vs tearing into the engine.

I used to have a GMC with an 8.1 that I ran a heavier weight in along with substituting one quart with Lucas oil treatment. It worked very well and quieted the engine as well.

 

[montegofd3s]

Is it more of a high pitch blower noise with some ticking and then just stops after about 45 seconds? I only ask because you mention its only on cold start ups so my thought was the primary or secondary air bypass pumps going out or some crud in the pump fan making noise. They are pretty loud in general, but usually sound like a high pitched shopvac.

 

[blatant]

Low coolant vote for heat exchanger/valley leak. You really need to crawl up there, from the underneath back of engine with light to review.

 

[Cruisin911]

Low coolant vote for heat exchanger/valley leak. You really need to crawl up there, from the underneath back of engine with light to review.

Not really. Pop off the engine cover and pull out the foam around the PCV valve. With a flashlight, any coolant leak in the valley plate area will become obvious. Its even better if you have a small camera that you can put in there.

 

[CharlieS]

Related to this, those endoscope type usb cameras are surprisingly cheap on Amazon. I picked one up a couple of years ago and they come in handy for looking in otherwise inaccessible spaces. Not saying you need one for this - since I've never had this failure I have no idea how obvious it is.