Timing chain cover. Questions... help.. while I'm in there... discussion

Hello all. I have an 07 tacoma with 175000 miles on it. It is in perfect shape for a northeastern truck. I am keeping this truck a long time. Now.. the issue..
I believe i have a timing cover leak. I am aware this is a big job. I do not believe it's above my capabilities tho. I am prepared to take on this job.
Most of questions are about what to replace when I'm in there. I believe at 175000 miles, I am about to come to the time where my water pump, oil pump, timing chain and tensioner, and obviously o rings and such.
Is it wise to replace the timing chain, oil pump, and water pump? Considering i am keeping this truck?
My main concern is the timing chain and oil pump. Is the oil pump integrated into the timing cover? I see repair kits, new pumps, and covers with pump... so I'm a little confused on what to get. And is there any writeup or guide for timing chain? I do have all data and I have looked at it quickly.. not extensively.. it's just written very technically and I don't always understand it's lingo right away. There was a link flying around the had some sort of guide, but that link is down. I tried Google, didn't find much. I did find a few tacomaworld threads but wondering if more exist. Looking to my tacomaworld friends for help and advice.. thank you!

 

At 275k+ I did the full timing set (chains, sprockets, slack adjusters - available as an OE kit outside of the dealer if you look) and VVTi cams, valve cover (classic valve/ti.ing cover weep/leak), and harmonic balancer because mine looked like shit (rubber cracking) and it had to come off anyway.

 

Ahhh. Thanks for the heads up about the harmonic balancer. I may just replace that too. It's 20 plus years old.

 

I have done head gaskets so I am familiar with the work involved. In my opinion, your mileage is low and it sounds like the truck has been taken care of. I think it is way too early to be replacing factory timing components even if you you reseal the cover. I would actually try to clean the area first to confirm if it is leaking from the typical area which is right by the power steering pump. If it is, I would try and apply Toyota FIPG (gasket sealer) and see if that will seal it. It looks like several folks on the form here have had success going that route. It’s not a lot of work and you have nothing to lose.

However, if you decide to reseal the cover, I would choose to inspect the components rather than just simply ordering them out right. Just my opinion of course.

As far as general steps go, I would suggest watching some of the videos on replacing the head gaskets as the initial steps can be used for the timing cover. I have a head gasket thread that I started several years ago, which has a lot of information in there that you might find helpful if you decide to take on resealing the cover. Aside from replacing any seal that you encounter, I would suggest replacing the water pump if it hasn’t been done.

 

I dunno. I been thinking a lot... how long till this damn head gasket goes too? Maybe I should just bite the bullet and get a new engine? I just contacted remans for a quote... anyone have experience with rebuild from
remans? Anyway... I'm thinking maybe 5 grand for engine? I will have over 2 grand in engine stuff just doing the timing chain cover and everything inside... why do all this work and have head gasket go? I do not see water in my oil cap.. I did one time.. but maybe something happened.. I haven't seen it since.. hmmmm... opinions please..

 

This truck is 20 plus years old... I just feel like the engine is on the brink of failure! Only 175 on it, but i think time is killing it..

 

Are you serious? Relax, clean off the area and confirm where it is coming from. If you confirm where it is leaking from, and it is the typical area, try putting some sealer on it first before taking the cover off.

 

I will definitely confirm thats where it's coming from before I do anything. Just not sure if I wanna patch it. I could get a couple more years out of it for sure with a patch.. but is it really worth it? I mean, these repairs are coming, no? Do these head gaskets on the truck have a long life span? I guess thats my only concern now. I do appreciate you telling me to pump the brakes!

 

Im not saying that you must patch it, I'm suggesting that approach since you appear to be risk adverse. If you are not willing to try a simple patch, I think taking on resealing the timing cover is probably too big of a job for you.

 

I appreciate that . But, no.. this is not above my skill level. I don't see how not wanting to patch a leak and actually fix it makes me look like I can't do the job makes no sense. But I see where you coming from. I appreciate the input.

 

My bad, I shouldn't have assumed anything. I don't recall telling you that you must patch it. I just simply gave you that as a low cost, low effort and low risk option. Good luck.

 

I just saw your head gasket thread.. very informative! I definitely saved it.

 

The only major concern for 4.0L head gasket failure in these trucks is 2005 and early 2006 model year trucks. Always the chance for a random failure, but where you are 2007 I would not 'expect' it.

As mentioned above, probably a good place to start is confirming 100% where the leak is coming from. 175k miles really isn't that much.

 

Thank you for that info. I greatly appreciate that. I can test the head gasket for leaks with a pressure test.. I should do that first before I go crazy.. so... If I did want to replace to timing chain cover, it wouldn't necessarily be an advantage to do the head gaskets if ok.. I'm probably going to far at that point.

 

You don't typically see timing cover failures on the 1GR-FE until about 350K+ miles.
I personally would not do the Chain, Tensioner, or Guides. Not unless I see sighs of Engine neglect.
Which can usually bee seen by the color of internals when looking down into the oil cap. (inspection camera helps).
Oil pump failure is almost unheard of, the least of my worries.

I would do the following; Idlers, Belt Tensioner, Water pump, Thermostat and Valve cover gaskets.