22RE timing chain = pulling the head?!

I replaced the timing set on my 93 22re a few months ago, and did so without removing the head.

I suspect the reason the book says to remove the head is to make it easier to seal the front cover. The front cover has to squeeze in between the head and the oil pan. Mine sealed up find though with some silicone gasket sealer.

Q

KaiS. wrote:

The head meets with the top of the timing cover, so to get the timing cover off (and back on again), without leaks it's a good idea to take the head off. I hate the way they designed this, but who the hell am I?? If you don't take the timing cover off, you can't get to the timing chain tensioner and guides, which are pretty important to replace. I've heard of people taking off the timing cover with the head still on, but it seems like you are just asking for a large oil leak that way, since part of the head gasket would have to be resealed. Sometimes people try to do that with RTV, but I have never seen it work without leaking. You might want to replace the cover while you're in there, mine started leaking after I replaced the timing chain, probably because they are almost impossible to get off without bending the top or bottom or nicking it somewhere (without you knowing it). Don't buy a generic one, though, they ALWAYS leak oil.

hope that helps.

oh, I don't know if yours is 4wd or what, but I was able to get my oil pan off by taking the support beam off, instead of lifting the motor. There is nothing connected to it anyways, on my 2wd drive at least.

This part of the 22r and 22re's was most def> Water pump on a 194kmi 4Runner sounds like its going so I thought I

If the water pump is going out, what on earth are you doing messing with the timing chain? There would be no compelling reason to replace these components unless they were worn - excessive noise, difficulty in setting ignition timing.

In engines with belt-driven valve timing it's a good idea to replace the water pump at the time you replace the belt as it needs to be removed anyway. Not vice-versa - and especially not with a chain driven cam.

-- Mike Harris Austin, TX

Agreed, if the water pump is going out that machine, I would just replace the water pump. Difference being about a few hundred bucks and quite a few days of work. But if you have close to 200k miles, I would probably have that chain checked if not replace by either yourself or someone that has done it before. I did this massive undertaking about

10,000 miles ago, and I believe that probably pulling the head and other stuff is the best way to go to ensure a good seal. When I changed my chain, I tried without taking the head out and I ended up crushing some of the head gasket in. Eventually I removed the head, which pretty much involves removing everything but the transmission. It's not that bad to do it youself, but don't expect to do the chain and head in a day or afternoon. If you do this, label and organize all the bolts together! It'll make life so much easier reassembling the motor.

If you do replace the chain, make sure to get a new tensioner and if your engine came with the plastic guides, buy the steel guides. It'll save you a lot of trouble, and maybe a timing cover, water pump, and maybe an engine too. I went for the LCEngineering timing chain kit, a bit expensive, but I think it's worth it.

I disagree- they are two different repairs - timing chain and water pump - they should be treated as such and done as needed and not "on spec." If the pump is bad he should replace it and drive on, regardless of the condition of the timng chain.

What you are suggesting is that he evaluate one particular component (timing chain) of his high-mileage engine. This is perhaps ill-advised if it causes him to replace this part "on spec" when it might make more sense to evaluate the general condition of the engine and replace the chain as part of a full overhaul when time, money and circumstances allow.

-- Mike Harris Austin, TX

I'm not saying that he should replace both or treat both as the same repair, but to consider doing that as well. It is a known issue for the

22re motors that if the chain hasn't been replaced and the motor has seen over 150,000 miles, that the chain should be seriously looked at and replaced if nessecary. The plastic guides in the motor have been known to be chewed up and the chain to start cutting into the water pump. After that you already know what happens per "spec". When I checked my engine with 120,000 miles, everything seemed fine, even the guides, but when I pulled the guides, they were eaten up from the middle where I couldn't see it.

So what I am saying is that you can just replace the water pump seperately and treated as a seperate repair, but seriously look into replacing the timing chain in addition if one has the time/money. A time when a full overhaul is due might be too late when the chain chews through the timing cover and into the water pump.

I replaced my timing chain at about 210,000 miles. It was getting noisy but not too bad. The chain, sprockets, and guides looked great. The problem was the rubber head on the tensioner that pushes on the chain, it was deeply grooved and would no longer take up enough slack. I bought a kit on Ebay that included all new parts including rubber coated steel guides for about $80. Installation only took me a few hours. Now it's as quiet as new.

Q

yippie wrote:

Yippie,

Worn guides would be a compelling reason to replace the timing chain as a stand alone repair. Noise would be a key indicator. If he is not suffering symptoms of a worn timing chain he might not want to take the time and trouble to replace it. Especially considering the relative difficulty of that repair.

It's a 200K mile engine. If he "looks into" replacing the timing chain, then he might as well look into doing a valve job, which leads to reconditioning the bottom end and new pistons... and by the time he's finished he's overhauled the engine when all that was really wrong was the water pump.

Not that there's anything necessarily wrong with this philosophy, but it really depends on his finances and his ultimate ownership intentions for his truck.

-- Mike Harris Austin, TX

I agree with that, finances and all, but it was just a suggestion, not a stamped in stone law that he should do a timing chain replacement. But I think it got quite a bit aways from the original post in which to replace the chain it would probably be more advisable to pull the head, imo. But you're right that by the time you finish doing the chain/head, you've pretty much rebuilt the motor except the bottom end. Anyways, just a difference of opinions for now.

It was my understanding this was a prudent measure in a high mileage engine. Figured while I was this far in I might as well go a little further now, rather than re-trace these same steps in the future as I do not turn over cars; I drive them into the ground.

But you're saying not to worry about the chain? And after further review, the service table in the manual makes no mention of the timing chain either so I'll just do the water pump.

Of course should the chain takes a s**te a year from now, I will most likely be thinking very bad thoughts about your parentage. ;)