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Corbet
04-12-2009, 02:56 PM
Looking at a new project. What all is involved to fix a 22R if the timing chain guides failed? Engine run well prior.

DaveInDenver
04-12-2009, 04:01 PM
Looking at a new project. What all is involved to fix a 22R if the timing chain guides failed? Engine run well prior.
Was the engine running when they failed? The 22R is an interference engine, so you might need to check valves if the chain broke.

If it's just broken guides and the chain did not break, then as long as you have not worn through the timing cover, it's a pretty straightforward repair. Get a new chain, gears, guides and tensioner, a few gaskets. Doing it the right way will also require a headgasket. It can be done in a weekend if things fall into place.

Corbet
04-12-2009, 04:57 PM
I will find out but I don't think the timing chain broke just the tensioner.

Sounds pretty straight forward. Its in a 84 mini. Still need to check the body for filler as there is no visible rust on the body:eek: I may be joining the dark side soon.:thumb:

DaveInDenver
04-12-2009, 05:27 PM
If the timing chain is intact, then you will likely be fine just doing an R&R. It's possible with broken guides or failed tensioner to jump a tooth, but that's not usually going to cause major damage. If you don't take care of a broken guide, the bigger chance to rub the timing cover with the chain until it wears through, which allows oil and coolant to mix. Once rubbing starts you really don't have a ton of miles to mess around.

So get replacement parts, I'm a OEM or equivalent person. Original parts were OSK or Aisin, but no matter IMHO the best option will be made in Japan parts. Note that this will be the OEM style guides, which are nylon.

Some people will recommend metal backed guides.

Depending on what month your engine is made, it may already have a double row timing chain. The switch was 8/84, which would be the later 22R block. The sure way to know is to look on the block at the bottom of the exhaust side and look for a cast flat area that looks like a flattened Mickey Mouse. It'll be right in the middle above the oil pan lip and it's not tiny. You can also measure the deck height, although this is not easy with the engine in place and dressed. But from oil pan lip to deck on '81-'84 blocks is about 0.200" taller than late engines (11.090" vs. 11.280").

Anyway, metal backed guides were standard on the 20R and early 22R. In 1984 Toyota switched to a single row chain with nylon guides, which are noticeably quieter. I replaced my OEM guides with metal backed guides, but they lasted 90K mile less then the original factory parts... So I went with all Toyota boxed parts on the new engine. Like I say, make sure to get Japanese parts if possible. Especially the tensioner, get the OSK or Toyota part here. The chain is expensive, so Engnbldr or 22RE.com are better options there. The gears, again the aftermarket is fine. If the Japanese parts are too rich for your blood, then US-made or at least Taiwan for sure. Avoid the parts from China and India if you plan to keep the truck more than 6 months.

The right way to do the job is to pull the head. If your timing guides or tensioner are broken, then you will have to pull the pan, too. You need to get the old parts out of there to keep from clogging the oil pump pickup.

But it's my thinking that the OE HG has a service life that's similar to the timing parts, so the FSM way of pulling the head is I think the right way. Don't skimp, get a good HG.

FWIW, Toyota sells a master gasket kit for the 22R and that's the way to go IMO. It's complete, main seals, valve guides, the whole deal if you're refreshing the engine. But if you're doing it on the cheap, I would stick with at least a factory HG and the timing cover gaskets. I used Fel-Pro timing cover gaskets the first time I did the chain (the metal backed time) and they weeped after about 10K miles. This time I got the Toyota gaskets and they are dry as can be after 22K now.

Also consider a new water pump and oil pump.

Corbet
04-12-2009, 08:11 PM
Think he current owner mentioned oil/coolant mixing so I might be in for more than a quick fix. I asked if valves/pistons connected, he said no.

DaveInDenver
04-13-2009, 05:59 AM
Think he current owner mentioned oil/coolant mixing so I might be in for more than a quick fix. I asked if valves/pistons connected, he said no.
This sounds pretty typical for broken guides (or just that you need a head gasket). Don't worry that you are in uncharted territory here. Engnbldr has timing covers that work and are 1/10th the cost of Aisin from Toyota. As long as the oil/coolant mixing hasn't been going on for a long time you should not be in trouble. The problem would be ruining the crank bearings or cam bearings if enough coolant dilutes the oil. Just take one step at a time, though.

Corbet
04-13-2009, 06:29 AM
The problem would be ruining the crank bearings or cam bearings if enough coolant dilutes the oil.

This was my concern

Red_Chili
04-13-2009, 06:43 AM
Your concern is well placed... though not necessarily just for coolant and oil. If the timing cover was worn through from broken guides, you may have additional damage to the engine - the aluminum (and steel :eek:) has to go somewhere. After my experience with the '93, I think any time I replace a 22RE timing chain where the above was the case (except the timing cover was not yet worn through), I will pull a bearing cap or three to check things out. The ones on the '93 were scored, but the crank was not yet damaged.

Shards of aluminum.

It was sad, too, because there wasn't much ridging on the cylinders and most of the hone marks were still visible. I overhauled it completely.

I could have gotten away with just replacing the bearings though, were I a (short term) cheep bastid, and didn't want to drive it for another 200K miles.

Be SURE to check the head and the block deck. If the HG was close to failing and the PO didn't keep fresh coolant in the thing, the block deck can easily be corroded due to electrolysis etc. Of course if you have to deck it, you need to do the full meal deal anyway (which is not really expensive).

Then you will have a dandy fresh '84 just waiting for an EFI conversion!!

Corbet
04-13-2009, 07:08 AM
my goal of this truck would be just to DD it and avoid the extra miles and fuel for the 80. Well hoping less fuel than the 80? So I'm hopping for a cheap fix or I may pass on the truck.

I'll also be more comfortable selling the 60 if I have another running vehicle in the stable.

Red_Chili
04-13-2009, 07:23 AM
Even a full overhaul on a 22RE ain't that expensive... especially if you just swap in a decent used longblock from Jim's Used Toyota Truck Parts.

C'mon, you know you want to join the dark side...

We are just giving you the worst case scenario. And even that ain't too bad. EFI will give just a bit more power and better mileage FWIW.

DaveInDenver
04-13-2009, 08:07 AM
Even a full overhaul on a 22RE ain't that expensive...
So true. If the block and head themselves are not trashed, a well enough done 22R rebuild can easily end up around $1K and give you another decade of service without drama. Even my new engine just tickled $2500 in parts (not including tools and a few sensors and stuff that was by and large optional) with a brand new, factory sealed short block, completely new Engnbldr head. I could have saved around $600 by having Gunn do the block and another $150 by having my old head machined for O/S valve and ported rather than the same with a new castings. If the price is right on the truck, I would assume with another $1500~$2K and a few weekends that you can give it a strong, new heart.

Rzeppa
04-13-2009, 06:30 PM
Doing it the right way will also require a headgasket.

No manifold gaskets?

Joe Calleja says he has a way of doing the timing chain without pulling the head. He described to me over the phone. I nodded my head while my eyes glazed over and went for the standard way, his way sound like a time saver but only if you REALLY know what you're doing.

X2 on the OEM guide and tensioner, most of the aftermarket crap is 20k mile or less.

Corbet
04-13-2009, 07:11 PM
peeked at it again tonight on the way home. Didn't knock on the owners door. Its got a repaint and spray in bedliner. Sunroof that is cracked. Dash is cracked. Birfs leaking bad. But buckets with seat covers? AC, power windows. Manual trans. Carpet is clean, inside is pretty good shape overall. I need to spend some time with a magnet on the body and pop the hood.

Tell me what else to look for and the best way to get a handle on the timing chain deal. I don't really want more than $500 ish in recon.

I have a compression tester and leak down tester in my tool box. Figure I will start there...

DaveInDenver
04-13-2009, 08:53 PM
No manifold gaskets?
If you pull the head, then yes, intake and exhaust.
Joe Calleja says he has a way of doing the timing chain without pulling the head. He described to me over the phone. I nodded my head while my eyes glazed over and went for the standard way, his way sound like a time saver but only if you REALLY know what you're doing.
I did it the first time leaving the head in place and that way does work if you are careful when you remove the timing cover (it's easy to tear the front section of the HG). I believe that dropping the pan is pretty much still necessary, more so unless you can account for all the pieces. Seeing the condition of my HG at 200K, I think thought that replacing it is the safest option if you're taking the time to do it right. But, yeah, there's no 100% answer here.

Corbet
04-13-2009, 09:43 PM
I'm comfortable pulling the head and pan. More to just see the overall condition of the engine as well. Nothing I hate more than to replace just a few things and button it up to find out I need to tear it all back down again.

Evrgrnmtnman
04-14-2009, 08:44 AM
FYI.........Don't go for the cheating way, do it the right way. And it maybe worth a call to Jesse at ATLR to get a price, he does great work and great prices.....303-487-6195 Office, 720-201-2214 cell...
You can also get a 22RE installed for $2,500.00

Red_Chili
04-14-2009, 10:40 AM
Seeing the condition of my HG at 200K, I think thought that replacing it is the safest option if you're taking the time to do it right. But, yeah, there's no 100% answer here.
Yeah, you *can* change the timing chain without removing the head, but with the chain and head gasket demonstrating a similar service life (unless all POs have been religious about coolant changes) why would you want to risk it?

There is a fair amount of movement between the block and head on a regular basis. Something's gotta give.

The cheater method was all the rage on minitruck boards for a while but I won't do it - after seeing my block deck corroded when I first got the Chili at 147K miles, which could have been prevented if the HG had been changed at the correct service interval.

Corbet
04-14-2009, 11:04 AM
Yeah, you *can* change the timing chain without removing the head, but with the chain and head gasket demonstrating a similar service life (unless all POs have been religious about coolant changes) why would you want to risk it?

There is a fair amount of movement between the block and head on a regular basis. Something's gotta give.

The cheater method was all the rage on minitruck boards for a while but I won't do it - after seeing my block deck corroded when I first got the Chili at 147K miles, which could have been prevented if the HG had been changed at the correct service interval.

OK, I'll do the HG, guides, and chain if I pick it up.

What I really need to know is what to look for during they buying process specific to that engine. Rest of the truck I can handle. Assuming the chain is not broken is it ok to let her idle with broken guides? Like to listen to valves, test ac etc...

DaveInDenver
04-14-2009, 01:11 PM
OK, I'll do the HG, guides, and chain if I pick it up.

What I really need to know is what to look for during they buying process specific to that engine. Rest of the truck I can handle. Assuming the chain is not broken is it ok to let her idle with broken guides? Like to listen to valves, test ac etc...
If the guides are broken enough to rub the timing cover, then you are on a very limit time budget. So I would probably avoid running it more than necessary, steel chain on cast aluminum is a pretty quick resolution to who has higher hardness...

Thing is with the chain rubbing it will sound like diesel, so you're not going to get a whole lot from the sound department.

I would personally just pull the valve cover and look at the valvetrain for scoring on the cam and followers (gotta love overhead cam here!). A good wear pattern will be nice and evenly bright across the whole cam lobe. Do a compression check and look for around 115 or 120 psi up there and +/- 10% high to low. That's about all you can do besides oil pressure while it's running and the oil pressure gauge on this truck (if it even has one) is basically a go/no-go kinda thing. My gauge is definitely not linear across its sweep, at 1/2 it's something like 45 psi and at 1/3 it's like 10 psi.

Look for weeping around the water pump and leaking oil around the half moons at each end of the valve cover and the front main on the front of the oil pump (you'll see oil on the lower crank pulley). Try to inspect around the timing cover as much as possible for leaks (would be coolant most likely) and under the intake. There are coolant passages under there that like to leak. That will tell you the general condition of the engine. For example if the half moons are not leaking it means someone is at least taking enough care to adjust valves once in a while and re-seal those. If they are leaking they are probably really old and have shrunk and hardened.

Corbet
04-14-2009, 07:45 PM
thanks this is what I needed to know.

I have an oil pressure testing kit too. Do you know what the spec pressure range is?

nuclearlemon
04-14-2009, 08:53 PM
after talking to a toy mechanic at petersons toyota in the fort, i did clampy without pulling the pan or the head. the pan was going to be a possibility dependant on the condition of the guides, but the head is rarely pulled according to him.

once you unbolt all the front cover bolts, (including a couple going in from the backside and one under the chain under the valve cover on the head), you slide the front cover off. if damage to the head gasket occurs, then you pull the head and replace. if the guides are missing chunks (or something else appears to be missing chunks), then you pull the pan.

shortly thereafter is where i documented a 22r doing 95 mph through idaho, without even skipping a beat or dripping a drop, so i'm pretty dang sure it worked:hill:

Red_Chili
04-15-2009, 08:37 AM
The key is what happens 20K miles from then...

DaveInDenver
04-15-2009, 12:20 PM
The key is what happens 20K miles from then...
This is what I saw in my own engine. I left the head in place at the 125K timing R&R and the HG at 187K didn't have a whole lot of life left in it (although nothing to indicate impending failure, it was showing signs at #3). Supposing someone else was not as anal as me (Toyota Red, distilled water, annual flushes, etc.), I'm fairly confident that the HG would have been in worse shape. We've talked about it before, I think the design service life on the 22R HG is prolly something like 200K km (125K miles) and being Toyota that means you have 1.5x or 2x margin, so 300K km (185K miles) is reasonably safe to assume for most engines. But beyond that it's borrowed time. So I think the service interval and procedure is by design, HG and timing components at some set mileage, probably 200K or 250K km, which works out to about 125K to 150K miles.