Subscribed to this one for sure. I'm wondering what caused the belt to break so soon after replacement. You said it was on the 3rd belt so it was replaced around 270k and only went 15k miles?
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PSA - 100 series timing belt (1 Viewer)
- Thread starter uzj100
- Start date
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You need to get in there and see that the timing marks are all good with your own eyes, and watch the compression test for that matter.
Something fishy about all this. Definitely dont think it needs a new engine, and theres no way it has no compression at all
JunkCrzr89
Competent Ignoramoose
Not setting the timing correctly before reinstalling the timing belt is the only thing that could cause no compression in any cylinder (I think).
- Thread starter
- #25
Yes. Working on it. Thank you so much for all the help.
So are you having your mechanic do a second compression test. Why no compression is no compression.
Leak down test useless, if belt is confirm off/busted. Which removing the RH timing cover is easy way see belt.
Next step is scope the cylinders. My bet is, not one hit on piston tops.
New T-belt job and drive another 90K, repeat!
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What brand was the belt? I’d be amazed that an oem belt “broke” from degrading from leaking coolant. In fact I don’t think we’ve ever had an oem belt break on mud. So I’m guessing it was aftermarket... or maybe it was oem and you paid someone to do the timing belt job and they never actually did.
also how does a broken timing belt break the water pump sprocket?
also how does a broken timing belt break the water pump sprocket?
As a general rule you are right. They don't generally break, independent of a bad pulley.
Saying: " Timing components put back and no compression at all. " Lacks detail I'd like. Pictures would say a lot! But it does imply they pulled the cover and belt was off and now replaced.
I'd think most cylinders' intake and exhaust valves would be closed, if belt off. So they get most cylinder with compression of 150 PSI cold. On other hand if engine did interfere, which is not likely from just trying to start with busted belt in non VVT. And interfered in every cylinder, unlikely. Then yes no compression.
If both cam sprockets sheared their knock pin. That could explain, if they sprockets now clocked wrong.. What the odds of that....
For belt breaks:
Most times, it's one of the idlers bearing goes out. But if water pump goes bad and leaks bad. That means it's pulley bearing/bushing is almost always shot. Any bad bearing/bushing and sooner or later it will take out T-belt
I have seen a break in mud, some years back. Was very old belt and from very hot dry regions IIRC. Search mud you may find it. We also saw a mouse take out T-belt, due to that 4" cover missing. Additionally a serpentine belt just took one out in last year. Bad tensioner can also can cause issues.
Saying: " Timing components put back and no compression at all. " Lacks detail I'd like. Pictures would say a lot! But it does imply they pulled the cover and belt was off and now replaced.
I'd think most cylinders' intake and exhaust valves would be closed, if belt off. So they get most cylinder with compression of 150 PSI cold. On other hand if engine did interfere, which is not likely from just trying to start with busted belt in non VVT. And interfered in every cylinder, unlikely. Then yes no compression.
If both cam sprockets sheared their knock pin. That could explain, if they sprockets now clocked wrong.. What the odds of that....
For belt breaks:
Most times, it's one of the idlers bearing goes out. But if water pump goes bad and leaks bad. That means it's pulley bearing/bushing is almost always shot. Any bad bearing/bushing and sooner or later it will take out T-belt
I have seen a break in mud, some years back. Was very old belt and from very hot dry regions IIRC. Search mud you may find it. We also saw a mouse take out T-belt, due to that 4" cover missing. Additionally a serpentine belt just took one out in last year. Bad tensioner can also can cause issues.
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- Thread starter
- #29
I have asked for a compression test and results on all cylinders. We shall see. Fingers crossed.
JunkCrzr89
Competent Ignoramoose
Pretty good odds, if the wrong person worked on it!
merbesfield
SILVER Star
Subscribed to this murder mystery. About to buy a 100 for my daughter and want to know if I should avoid VVTI. Which is likely anyhow due to being too expensive by they are newer.
trdcorolla
SILVER Star
From my Mud reading, 98-05 non VVTi are non interference and 06-07 are interference engines. The VVTi's do have more power but it looks like they have smog air pump problems which can be fixed for $$$ or bypassed with a kit and it looks like they also have weaker fuel pumps. The cam seals can't be replaced without removing the cam shafts unlike the 98-05. You do gain nice LED tail lights with the VVTi.
merbesfield
SILVER Star
- Thread starter
- #36
Update
I received a video with the truck running. It sounds correct and good.
When the belt broke, it destroyed the crank position sensor. A new sensor was installed a few days ago and that is when there was zero compression on all cylinders. The new sensor from Toyota was actually bad. A new crank position sensor was put in today and it fired up and sounds ok on the video. Compression on bank 1 was 170-170-170-150 and on bank two 170-170-170-150.
I am hoping everything is ok.
Persistence and ih8mud family paid off.
Thank you for all the assistance!
I received a video with the truck running. It sounds correct and good.
When the belt broke, it destroyed the crank position sensor. A new sensor was installed a few days ago and that is when there was zero compression on all cylinders. The new sensor from Toyota was actually bad. A new crank position sensor was put in today and it fired up and sounds ok on the video. Compression on bank 1 was 170-170-170-150 and on bank two 170-170-170-150.
I am hoping everything is ok.
Persistence and ih8mud family paid off.
Thank you for all the assistance!
JunkCrzr89
Competent Ignoramoose
Although well within the minimum spec, there may be something amiss with your #7 and #8 cylinders. 20 psi is more than the max allowable 10% variation from 170, suggesting worn rings or damaged valves. Are these numbers from a dry or wet test?
- Thread starter
- #38
Do not know. What is a dry vs wet?
285k on the engine.
At this point id have a hard time anything was done right. No offense to your trusted mechanic, but that's a mighty big jump to go from "needs a motor" to a CPS. Assuming you hadn't asked a bunch of internet strangers for a second opinion, you may have been taken for a ride by this "trusted" mechanic.
If it runs well, it runs well. I wouldnt trust the compression figures unless I did it myself.
If it runs well, it runs well. I wouldnt trust the compression figures unless I did it myself.
- Thread starter
- #40
Long story. Hit the pm. 
