Cam Shaft Seals - Should They Be Replaced?

[neo mrosko]

Hi,

I'm looking for some reliable input regarding replacement of the cam shaft seals when doing a timing belt change on a 02 4runner 3.4 L V6.

I had a Toyota shop do the timing belt change / water pump / drive belts and I supplied the parts as a kit. In the kit were new Toyota cam shaft seals. While replacing the timing belt the shop called me and said there'd be an additional hour of labor charged to replace the cam shaft seals and asked me if I wanted them replaced even though the old ones were OK. I left the decision up to the mechanic and he decided not to replace them. I am wondering if that was a mistake and how common is it for the cam shaft seals to fail on this engine?
I appreciate the input. Thanks.

 

[Lamer]

I just did the timing belt / water pump / thermostat work at a shop. my cam seals were slightly leaking at 260k miles. he said I would probably be ok for a while but since they were in there already I had them changed. I also had the crank seal changed.

in your case, if they are not leaking, then you should be ok. as per the toyota tech. if they arent leaking they typically stay away from them.

 

[neo mrosko]

Thanks, this engine has 127k on it.

 

[LittleCaesar]

If they aren't leaking, it can be a toss up. An hour though? Should be half that time on a slow day with non truck tools.

 

[mtbtim]

There's two schools of thought when tearing that deep into a motor, replace every wear item you can while you're in there because it's a lot of labor to go back in if something fails or leaks and then there's the line of thought, if it ain't broke, don't fix it.

I pretty much subscribe to both schools of thought. When [MENTION=102606]infamousRNR[/MENTION] and I did his timing belt job, we replaced everything. When we replaced his auto transmission, we could have replaced the rear main seal but opted to leave it alone because there was no signs of leaking whatsoever.

OP, with the mileage you have on your engine, you're probably going to be just fine. Before I started doing more of my own wrenching, I paid for timing belt jobs. Not once did the shops recommend replacing the camshaft seals, crankshaft seal, idler pulleys or timing belt tensioner. But, they always recommended replacing the water pump. I think a lot us go overkill with the things we replace when doing a job like the timing belt. But, with a kit like the one aircabinman sells on Ebay, replacing all the associated parts is cost effective.

 

[nobb]

Elastomers go bad not only with mileage, but time as well. This is a 20 year old rubber part. Luckily, the cam seals don't see as much heat as the crankshaft seal so they won't deteriorate as fast. When I did my timing belt, the lower crankshaft seal was noticeably darker and harder than the upper camshaft seal from all the heat.

 

[thegipper]

My cam shaft seals were leaking on my 97, that engine had 216k miles on it. I would have had them replaced. It took me maybe 15 minutes to replace them.

When I had to put in a replacement engine, I replaced every single seal including the rear main. The parts aren't that expensive and all of the seals were pretty easy to replace.

It'll probably be fine but yeah, you should have replaced them.....

 

[mtbtim]

Shoulda, Coulda, Woulda. My 2000 now has 180k with the original cam seals. Most of us go overkill with our rigs because we love them so much and we're anal about their maintenance. Is the OP going to be fine until it's time for the next timing belt change in around 100k miles? I'd bet money on it. And, even if he does develop a slight leak at one of the cam seals, it's not a big deal. There's millions of people driving vehicles with oil leaks. My 99 Subaru had leaks galore and burned oil too. Did I bother figuring out where the oil leaks were and spend the time and money to fix them? Nope. I just added a quart of oil between oil changes. Problem solved.

Think about our well-known valve cover gaskets that leak and need replacing. What percentage of the 3rd Gens on the road still have leaking valve cover gaskets? I'd say that percentage is pretty high. Are the owners losing their minds over it? Probably not, because it seems most 3rd Gen owners aren't the type that wrench on their rigs anyway and are sort of clueless what's going on with their motor. We have tons of 3rd Gens in the California Bay Area and a high percentage of the drivers I see are soccer moms, older folks, and other folks that don't look like they turn a wrench using them to get from point A to B. As long as they start and get them to where they are going, they drive them merrily down the road oblivious of the LBJ failures and The Dreaded Pink Milkshake that keep guys like us up at night.

So, what am I trying to say. OP, drive and enjoy your rig and don't worry about it. Think about having a shop replace the cam seals on your next timing belt job if you still own the rig. Or, better yet, take on the challenge and do the next timing belt job yourself. Happy Trails!

<iframe width="560" height="315" src="https://www.youtube.com/embed/vHC46ypHxWc" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>

<iframe width="560" height="315" src="https://www.youtube.com/embed/mErd7xoBS9I" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>

 

[Desertwind16v]

I've been working as a tech for a Toyota dealer for over 15 years now and the only time I have ever replaced cam seals on a 5VZ was on mine earlier this year. I had around 272k on the engine at the time and they were not leaking. I was doing VCG at the same time so they were very easy to do. You were probably fine to leave them alone.

 

[Mark313]

Yeah bc 4Runners don’t brake down. They simple get fed up n quit.

 

[psea17]

reviving an old thread. did the timing belt job about 25k mi ago. changed the cam shaft seals. i suspect the passenger side is now leaking. not sure what else it would be other than possibly having the wrong oil put in it during an oil change. (only day that because when i put 2qts of conventional in it the leaks seemed to have stopped.)

wonder how much of the timing belt replacement steps i have to do to replace it. do i need to remove the harmonic balancer, water pump, etc? just trying to get mentally ready and kind of hoping i can avoid some steps. any way to access via top of the engine? guessing not.

also anyone know how difficult it would be to replace the cam shaft sensor's wiring? truck has 260k. it looks like that wire has seen better days.

THANKS!

 

[Bad Luck]

reviving an old thread. did the timing belt job about 25k mi ago. changed the cam shaft seals. i suspect the passenger side is now leaking. not sure what else it would be other than possibly having the wrong oil put in it during an oil change. (only day that because when i put 2qts of conventional in it the leaks seemed to have stopped.)

wonder how much of the timing belt replacement steps i have to do to replace it. do i need to remove the harmonic balancer, water pump, etc? just trying to get mentally ready and kind of hoping i can avoid some steps. any way to access via top of the engine? guessing not.

also anyone know how difficult it would be to replace the cam shaft sensor's wiring? truck has 260k. it looks like that wire has seen better days.

THANKS!

The camshaft gear has to be removed to do the seal so timing belt must come off

 

[mtbtim]

Same question and two different threads. Ok.

 

[psea17]

Same question and two different threads. Ok.

hey tim! sorry about that. only did it because they were old threads. appreciate your input on the other thread! regards, psea