and the plot thickens 
Multiple issues, need help diagnosing 4.7 V8 (1 Viewer)
- Thread starter gthoman
- Start date
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- Thread starter
- #82
Got the timing covers off and checked the marks, and somehow they were off by a couple of teeth. Here are the pictures:
LexusGX470 - Google Drive
So would next steps be to get the marks lined up and do the compression test? Or since there are exhaust fumes in the coolant, not going to matter since it would seem the gasket is gone and so either that needs to be replaced or engine replaced?
LexusGX470 - Google Drive
So would next steps be to get the marks lined up and do the compression test? Or since there are exhaust fumes in the coolant, not going to matter since it would seem the gasket is gone and so either that needs to be replaced or engine replaced?
Start with the most obvious and easiest first. Get the belt on proper and see if it starts. If no, then do compression and redo the coolant test.
Half k cruiser beat me to it. See what happens once you get the timing belt issue fixed first. The coolant in the exhaust could have been a false positive. I wonder what caused the belt to skip in the first place? I'd consider replacing the T belt tensioner if it's the original one.
- Thread starter
- #85
Thanks for the replies, will give that a try next.
I did replace the tensioner when I replaced everything else, and it did seem like it was locked(really hard to move back and forth), which might have been the reason. Or that we had recently gotten a boat which put a lot more strain on engine than normal, not sure??
I did replace the tensioner when I replaced everything else, and it did seem like it was locked(really hard to move back and forth), which might have been the reason. Or that we had recently gotten a boat which put a lot more strain on engine than normal, not sure??
Get the timing right first. I would inspect the throttle body for leaks. It can introduce a little coolant and give you headgasket symptoms.
1. Fix timing
2. Compression test
3. Test exhaust for coolant
4. Check throttle body for leaks and fix/bypass the coolant loop there.
1. Fix timing
2. Compression test
3. Test exhaust for coolant
4. Check throttle body for leaks and fix/bypass the coolant loop there.
alia176
SILVER Star
I vote for fixing the timing, then drive it to see if you get the same CEL codes again. This is a good find.
- Thread starter
- #88
So, cleaned up after Florence, not too bad where I was, couple trees and a mess of debri, but am going to try to get outside after work and try to get the timing right.
Had a question, most videos/docs always talk about replacing timing and water pump at the same time, so removing most of the front end, since I'm just needing to remove the belt and adjust the timing, do I still need to remove the fan bracket, move the alternator out of the way, etc?? I'm hoping I can see what needs to be done tonight, but any help would be appreciated
Had a question, most videos/docs always talk about replacing timing and water pump at the same time, so removing most of the front end, since I'm just needing to remove the belt and adjust the timing, do I still need to remove the fan bracket, move the alternator out of the way, etc?? I'm hoping I can see what needs to be done tonight, but any help would be appreciated
Since you aren't removing the T-Belt, I would just put the pin in the belt tensioner to keep it locked, then loosen it but leave it installed. You can leave the fan bracket and W/P, but remove the crank pulley and the covers. reset the timing, then spin it by hand a few times to ensure everything is spinning as it's supposed to. Then reassemble. If the plugs are out and all that, you could try another compression test. If the plugs are installed and it's ready to run, I'd send it and see what happens. I'll almost guarantee it will run. That said, once it's running on it's own, it might reveal the next issue which could be a headgasket problem. Keep us updated!
- Thread starter
- #90
Thanks, will hopefully get some time to work on it tonight. The plugs/coils are out, so will do the compression test after its lined up. Questions about the tensioner:
I'm hoping I can find the pin, but if not, is there something else I can use or would an auto store have it?
How can you compress the pin with it attached?
I'm hoping I can find the pin, but if not, is there something else I can use or would an auto store have it?
How can you compress the pin with it attached?
I used a small screwdriver. If you don't have a small enough screwdriver, you can substitute a drill bit.
Also, the book says to advance the timing half a tooth on the drivers side and a full tooth on the passenger side. Or Vice Versa, I can't remember now. Do you have the FSM?
- Thread starter
- #93
I think I have a service manual somewhere, was just following some videos/links I had found, but they lined it up exactly on the marks for TDC. But I also thought the 2003-2009 had the same engine which I guess was wrong(since 2003-2004 have non-interference engines and 2005+ do), so I'll see if I can track it down, or if you find out for a 2003 GX470, let me know. Thanks again!
As long as it lines up on the timing marks after spinning it by hand a few times you should be good.
How is this coming along?
- Thread starter
- #97
Sorry, was out of town and just got back, have most of the covers off and am having an issue removing the fan, but hope to remove that tonight and line up the marks. Then will start with the compression tests.
Nice!
- Thread starter
- #100
Not yet, been really busy this week at work and haven't had much time to work on it. Tried for a little bit last night to wiggle off the fan, but still seems stuck. I remember the first time the fan being a struggle, but not sure it was this bad. Anyone have any tricks? I'll keep it updated as I progress, but might be slow since I also have some more travel coming up.
