It is worth doing a top end rebuild with leaking valve seals (1 Viewer)

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Jan 11, 2019
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Sacramento
Hey all,

I'm gearing up to catch up some maintenance on my 1997 FJZ80. I've done a mild tune up at 170k and going to do a major tune up right now, at 230k. This includes replacing leaking valve cover gasket, as well replacing almost all of the gaskets, coolant lines and vacuum lines under the intake manifold. Removing & cleaning injectors, dizzy oring, coil pack, fuel pressure regulators, PHH, deleting rear coolant lines, as well as replacing power steering pump& hoses. My FJZ has three noticeable leaks, one is from power steering pump, one's from rear main seal (I think) and the third one is from what I assume to be leaking valve seals. I burn about a quart of oil every 500-700 miles. I *think* my head gasket is still fine as my coolant looks great & my oil looks great also. However, while I'm in there and doing all this work, would it be worth to go ahead and refurbish the head, or just wait til the head gasket blows. If I'm to do the head gasket, is it worth doing all the timing belt components & oil cooler? I have replaced the front main seal & oil pump seal few years ago and it's still fine. Is it easier to take the head off with the block still in the truck, or go ahead and pull the whole engine+tranny and service it all out of the engine? And If I do pull the engine, is it worth to go ahead and get it completely rebuilt with new bearings & rings.
Someone take me out of this rabbit hole, thanks lol.
 
Several things: first, the 1FZ-FE doesn't have a timing belt. It has a timing chain:
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Second, and take this for what it's worth, pulling the engine to change the headgasket is always a better option. Just wait until you have to crawl into the engine compartment to reinstall the head. Don't buy into the "your headgasket is a problem waiting to happen" philosophy. Take care of your cooling system and you won't have a problem; let the engine overheat, and well...

As to whether you should get into the timing gear and oil pump while the head's out, they are in a different area. Pulling the head isn't going to help gain access to them. If it ain't broke...

Third, and again, just my 2¢, if you're concerned about oil usage, I'd replace the plug seals in the valve cover and the valve seals (you can do this with the head on). That'll take care of a lot of your oil loss. If it doesn't, then you'll know you need a valve job, and it won't have cost you several paychecks.

Fourth, there's no need to replace the bottom end components unless you have identified a problem; i.e., low compression, rod knock, etc.

Finally, and this is from personal experience with several 80s, I'd look at the oil pan seal between the upper and lower pan, before I spent the money on the rear main seal. I've replaced every rear main seal on every 80 I've owned and they still leaked; I'm convinced it's the pan.
 
Several things: first, the 1FZ-FE doesn't have a timing belt. It has a timing chain:
View attachment 3253583

Second, and take this for what it's worth, pulling the engine to change the headgasket is always a better option. Just wait until you have to crawl into the engine compartment to reinstall the head. Don't buy into the "your headgasket is a problem waiting to happen" philosophy. Take care of your cooling system and you won't have a problem; let the engine overheat, and well...

As to whether you should get into the timing gear and oil pump while the head's out, they are in a different area. Pulling the head isn't going to help gain access to them. If it ain't broke...

Third, and again, just my 2¢, if you're concerned about oil usage, I'd replace the plug seals in the valve cover and the valve seals (you can do this with the head on). That'll take care of a lot of your oil loss. If it doesn't, then you'll know you need a valve job, and it won't have cost you several paychecks.

Fourth, there's no need to replace the bottom end components unless you have identified a problem; i.e., low compression, rod knock, etc.

Finally, and this is from personal experience with several 80s, I'd look at the oil pan seal between the upper and lower pan, before I spent the money on the rear main seal. I've replaced every rear main seal on every 80 I've owned and they still leaked; I'm convinced it's the pan.
Typo, I meant the chain& its guides and the sprocket (all are cheap).

For the timing chain & cover it’s a lot easier if I was to pull the head and install the gasket.

I’ve read a threads on replacing the valves seals with the head still one, and it looks WAY more difficult than just pulling the head out. That’s just the impression I got. I got new spark plug seals but I don’t think they’re the culprit as last time I pulled my spark plugs there were clean.

I know it’s possible to drop the upper oil pan with the engine but at that point might as well pull the engine if I have to pull the drive train out. I’ll take a look at the lower oil pan, doesn’t hurt to reseal my oil pan while at it I guess.
 
I’ve read a threads on replacing the valves seals with the head still one, and it looks WAY more difficult than just pulling the head out. That’s just the impression I got. I got new spark plug seals but I don’t think they’re the culprit as last time I pulled my spark plugs there were clean.


at the shop we pretty much only changed the valve stem seals with the head on, if you have shop air theres kits that allow you to pressurize the cylinder to help keep the valves in place. other than a stem seal puller there really isnt any special tools needed. the only time that stem seals were changed with the head off was when the motor was getting rebuilt or the head had to come off for some other reason
 
NP, I'm not a perfect typist either.

You are correct that the head has to come off to access the timing chain, but I wouldn't pull the front of the engine off, just because I had the head off (I didn't actually), unless I knew I had a timing chain/gear problem; just my 2¢

Pulling the head is not easier than replacing the valve seals in situ. Ask anyone who's pulled the head. Especially anyone who's pull a head without pulling the engine.

The plug seals seal the engine compartment, not the plugs themselves. You'll lose a lot of oil (in vapor) that you'll not see as a "leak" over time.

I agree that pulling the oil pan(s) without pulling the engine isn't a slam dunk choice, but you do not have to pull the drivetrain to replace the rear main seal; the transmission just needs to be slid back. Yes, it's decoupled, but that isn't removing it. Sliding it back and forth isn't the hassle that pulling the thing out and trying to line it back up is.

I only meant to provide the observation that it's cheaper to look at the pan seal that to go through the hassle of replacing the rear main seal, only to find you still have an oil leak. Of course, if you pull the engine, you can do both and then you don't have to guess anymore.

You're asking all the right questions. Now you just have to decide what the right answers are for you.
 
IIRC, I replaced the valve cover gasket at 240K miles (seepage), but my '97 1FZ-FE was always burning oil at ~1qt/2.5K. So annoying.

A reliable 3 years and 40K miles of assiduous engine oil top-offs later, I noticed an unusual amount of coolant loss. I promptly parked the LC, got busy on the internet/ih8 and amassed a list of OEM parts to build a brand new, 100% Toyota 1FZ-FE long block including accessories, EGR/VSV, manifold-to-exhaust-tip, etc. 6 months later, I was then blessed with *noticeably* more power, zero error codes and nada oil consumption even running full synthetic 5W-30.

How you want to maintain your 80 is a very personal project bound by time, energy and $. Yes, some will treat their 80 like a pile of undervalued dog sht because it is. Others will only give their Land Cruiser the very best treatment because the economics justify it.

I'm very impatient and irrational when it comes to the condition of my vehicles so I measured twice and cut ONCE. I will only *read* about doing it any other way.

Good luck!

12K mile young 1FZ-FE pushing 37s

IMG_1449.jpeg
 
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NP, I'm not a perfect typist either.

You are correct that the head has to come off to access the timing chain, but I wouldn't pull the front of the engine off, just because I had the head off (I didn't actually), unless I knew I had a timing chain/gear problem; just my 2¢

Pulling the head is not easier than replacing the valve seals in situ. Ask anyone who's pulled the head. Especially anyone who's pull a head without pulling the engine.

The plug seals seal the engine compartment, not the plugs themselves. You'll lose a lot of oil (in vapor) that you'll not see as a "leak" over time.

I agree that pulling the oil pan(s) without pulling the engine isn't a slam dunk choice, but you do not have to pull the drivetrain to replace the rear main seal; the transmission just needs to be slid back. Yes, it's decoupled, but that isn't removing it. Sliding it back and forth isn't the hassle that pulling the thing out and trying to line it back up is.

I only meant to provide the observation that it's cheaper to look at the pan seal that to go through the hassle of replacing the rear main seal, only to find you still have an oil leak. Of course, if you pull the engine, you can do both and then you don't have to guess anymore.

You're asking all the right questions. Now you just have to decide what the right answers are for you.
I see, I thought the spark tube seals only stop the oil from going into the tube.

I didn’t know I don’t have to drop the transmission, that makes it a lot easier.

I think I will go ahead and try to replace the valve seals with the head attached. Just in case I change my mind, anyone has a recommendation for a machine shop near Sacramento, CA?

I see a lot of different vendors for injector cleaning, anything local or outstanding?
 
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I see, I thought the spark tube seals only stop the oil from going into the tube.

I didn’t know I don’t have to drop the transmission, that makes it a lot easier.

I think I will go ahead and try to replace the valve seals with the head attached. Just in case I change my mind, anyone has a recommendation for a machine shop near Sacramento, CA?

I see a lot of different vendors for injector cleaning, anything local or outstanding?
I cleaned mine with fresh gasoline and a toothbrush.

Yes, those part numbers are correct. For all 1FZ Land Cruiser engines, 1993-1997.
 
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I see, I thought the spark tube seals only stop the oil from going into the tube.

I didn’t know I don’t have to drop the transmission, that makes it a lot easier.

I think I will go ahead and try to replace the valve seals with the head attached. Just in case I change my mind, anyone has a recommendation for a machine shop near Sacramento, CA?

I see a lot of different vendors for injector cleaning, anything local or outstanding?
Kevin at Bud Walmers in Orangevale is awesome. PM me if you want the back story.
 
Kevin at Bud Walmers in Orangevale is awesome. PM me if you want the back story.
I read over your build thread, will give him a call if I go that route.

I also want to avoid as much downtime as possible, especially with shipping injectors and etc. Any downsides to using these;Toyota Land Cruiser 4.5L 1FZFE Fuel Injectors Denso Best Upgrade 12-Hole Spray! | eBay - https://www.ebay.com/itm/204198711700?hash=item2f8b311194:g:qMIAAOSwJrdcdwXD&mkevt=1&mkcid=1&mkrid=711-53200-19255-0&campid=5336682098&toolid=10001&customid=3174X601276X9edc8b3dede393c97935956088766b40?
 
I went with:
Home - https://fuelinjectorspecialists.com/

they were reasonably priced and quick turnaround. So far so good.

I'm surprised you found my "build" notes. I know the approach I took was not common, but, for me. it's what worked. I've mentioned this in a few other threads, but, the threshold for pulling the engine (Trans & TC) is to me really low. Because EVERY "job" is so, so much easier.

Keep us posted & have fun.
 
I pulled my engine and had it rebuilt primarily due to valve seals. My oil consumption was roughtly 1qt every 3K miles for several year however it had started to increase over the past year and a half. Right before pulling the engine, it was 1qt every 1K miles. On top of that I had a valve cover gasket leak, spark plug seal leak, lower oil pan leak, upper oil pan leak, rear main leak, and 275K miles on the original headgasket. I plan to keep the truck till I die and figured it was time.

I purchased the LCE master rebuild kit but replaced a few of the items in the kit with OEM parts (seals and any rubber bits). I brought home my original pistons and was surprised at the layer of cooked oil on top of each piston from the leaking valve seals.

Total cost was about $3000 with the rebuild kit, labor, and parts but I wouldn't hesitate to go this route again.
 
Got around to pulling the plugs today, 4/6 are in a pool of oil. Plugs look like the might be burning oil as well, maybe you guys can tell me. I’ve attempted to do a compression check but it didn’t work out. The gauge wouldn’t hold pressure, and i was getting all sort of wierd readings on a cold engine. I felt like it couldn’t have been in accurate as some cylinders got a little bit of oil when i pulled those plugs. Cylinder 1 and 6 were reading 150 and 120. I’ll try to retest tomorrow.
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View attachment 3260407
I have a video but on a few it would hit 180 and go back down to 0. I’ll see what’s up with the gauge tomorrow. It’s a rental from NAPA.
If you have oil in the cylinders there is no point in a compression test; it won't be accurate. Adding oil into a leaking cylinder is the test for leaking valve seals versus leaking piston rings.
 

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