Should I rebuild my 1FZ-FE? How to make an informed decision? (1 Viewer)

[bob82pigdog]

There are 296,000 miles on my LX450 and I just blew the head gasket on the way home from my last wheeling trip. I pulled over on the side of the highway to start a DVD for my 3 year old, and saw that my Ultra Gauge was reading 249 degrees F, so I pulled deeper off the shoulder and saw the big clouds of steam coming out the exhaust and from under the hood as the motor was misfiring and stumbling. I promptly shut down the engine.

I got it towed home and see no oil/ coolant milkshake. I plan to do a compression test and leak down test just to get as much information as I can before I start the work. As far as I know this was the original head gasket. I have the feeling it had been burning little amounts of coolant all along. I found myself topping off the reservoir a few times a year. And I think this time it just got low enough without me noticing that it lost the last little bit in the reservoir and got too hot once the highway air stopped coming in. Water pump, thermostat, belts, are all new and no leaks. PHH replaced recently etc.

I am planning on tearing it all down sometime January when I make some space in the garage and doing all the work. The main question, am I kidding myself that I can get away with just a head gasket and top end rebuild or at this mileage do I seriously need to consider a full bottom end rebuild as well? Or should I just wait to see what the cylinder walls look like when I get in there and let that tell me? Any input appreciated. Sorry for the novel. Thanks!

 

[cowboyjack]

How long do you plan to keep the vehicle?

I’d answer that first, then pull the head and see how things look.

My head gasket blew at 180k, pulled and rebuilt the head and all looked “well enough,” so buttoned it back up.

Then spun a bearing three weeks later due to a loose nut on the rod cap. Totally unexpected. Can’t see it unless you pull the oil pans. Never seen one before on an original factory engine in 50 years of working on cars, let alone on a Toyota.

Plan to keep my Cruiser until I die, so did a full rebuild with a new OEM Mr. T short block. So the head rebuild wasn’t “wasted,” but it would have been a little cheaper to do it all the first time. But who knew?

 

[Cass007]

So I had something similar happen with my Cammo truck and here is what I learned:

1. Spoke with Ryan at OTRAMM a while back and he said very rarely does the bottom end need to be rebuilt (which was great since the cost hurt my feelings). That being said, if I ever have a bottom end done it will be by his shop.

2. I took the time and followed the Blue Devil head gasket sealer directions and now my truck will still bubble a bit in the overflow after shutoff, but will run all day between 184-195*F and I mean all day ... like start it at 7am to go wheeling and shut it off at 5pm when I get home. It's a patch at best for sure, but it's getting me on the trails and I watch my temps like a hawk. When the truck tells me it's done I will do the proper repair, but until then I still get to drive it and prep for the head gasket on my terms.

3. You can likely get the head gasket done yourself with the FSM, some YouTube and MUD help after paying a shop to get the head back on point (I see this in my future, possibly x3), but setting up a bottom end is a whole different animal, at least from my time in the tuner world. IMHO the top end is wrenching and following directions. The bottom end is closer to art and experience.

 

[BILT4ME]

Make sure you didn't just blow a hose and run out of coolant before you tear the head off.

Please do a PROPER diagnosis.

 

[Desert Dino]

Make sure you didn't just blow a hose and run out of coolant before you tear the head off.

Please do a PROPER diagnosis.

"big clouds of steam coming out the exhaust"

 

[slow95z]

"big clouds of steam coming out the exhaust"

I have seen rear heater lines go and cause it to look like that.

 

[Woofythewolf]

I'd say just redo the top end and see how far it goes. You're probably fine, although seeing the condition of the camshaft bearings will give you an idea of what the bottom end bearings will look like. Not how tight the bolts are though, that rod nut being loose is pretty crazy

I did my top end at 360k-ish miles (odometer broke at 290k) and its been a set of brake pads since (so maybe 10-15k miles?) with no issues.
I did have to replace the head since I drove it leaking bad (topping off every time I drove it) for 6 months to/from school and work, and when I took it off it was warped over 30 thousands. The shop said straightening it that much would probably cause cracks, and just shaving the heads would the camshaft bearings out of alignment.

Here's a warning though: if you try the bars leak stuff and drain the system to do the head rebuild, FLUSH IT SUPER WELL.
I didn't, and obviously the stuff cures when exposed to air for long periods of time, so it cured in my radiator when I drained it without flushing the bar's leak out. That was an expensive mistake.

 

[Red Merle]

I have seen rear heater lines go and cause it to look like that.

That's what happened to mine. I didn't realize that was the issue until I was pretty far into the head gasket job. I don't regret doing the job, but it would saved me a lot of money if I would have just deleted the rear heat.

 

[bob82pigdog]

Thanks for all the responses, guys!

"big clouds of steam coming out the exhaust"

Also, "engine stumbling and misfiring" Never seen a busted coolant hose cause misfires and engine running like crap, but hey I am all for making a 100% informed decision and avoiding unnecessary work! Like I said, I'm going to do a compression and leak down test. Anything else you had in mind @BILT4ME that I haven't said that would give better evidence?

Also, I'll give the rear heater lines a look, the rear heater is already on the list as getting removed, the metal lines are pretty rusty under there.

So far it seems like there is a chance I'll be OK just doing the top end IF the signs look good and IF I actually have blown the head gasket. The motor has always run really well in the past 20,000 miles or so I've owned it.

 

[BILT4ME]

Thanks for all the responses, guys!



Also, "engine stumbling and misfiring" Never seen a busted coolant hose cause misfires and engine running like crap, but hey I am all for making a 100% informed decision and avoiding unnecessary work! Like I said, I'm going to do a compression and leak down test. Anything else you had in mind @BILT4ME that I haven't said that would give better evidence?

Also, I'll give the rear heater lines a look, the rear heater is already on the list as getting removed, the metal lines are pretty rusty under there.

So far it seems like there is a chance I'll be OK just doing the top end IF the signs look good and IF I actually have blown the head gasket. The motor has always run really well in the past 20,000 miles or so I've owned it.

Running at 249°F is definitely a problem.

The steam from under the hood COULD be a ruptured hose or leaking hose or failed radiator. A typical failed head gasket does not cause steam under the hood EXCEPT when it overheats to this level and is blowing steam out the radiator and overflow bottle.

The stumbling and misfiring COULD be from a leaking head gasket causing the misfiring. It could also be from the severe overheating and causing ping and knock.

I agree with the compression test and leakdown test.

I missed the note on all the hoses and PHH had been recently replaced. Sorry.

As far as the bottom end being rebuilt or not is a crapshoot. I would pull it apart, then make that call. There are many here that have that mileage and the bottom end looks great.

What has your oil pressure been to date?

Otherwise, plan on pulling it, go through it completely, check bearings install all new seals, and have a new truck!

Sorry for your loss.......

 

[cody c]

Consider a V8 swap. If you need to have toyota parts look for a good 4.7 litre, if not look for a good 5.3 or LS.

Part out motor, or sell as a donor/rebuild to recoupe some costs.

 

[bob82pigdog]

How long do you plan to keep the vehicle?

I’d answer that first, then pull the head and see how things look.

Then spun a bearing three weeks later due to a loose nut on the rod cap. Totally unexpected. Can’t see it unless you pull the oil pans. Never seen one before on an original factory engine in 50 years of working on cars, let alone on a Toyota.

I plan on keeping it for a loooong time. So, if you were me, or youd had to do yours again, would you pull the lower pans to check and make sure everything looked OK? Would it have even been obvious anyway had you checked things out down there?

 

[Tools R Us]

My evaluation would be: Check for codes. Fill the cooling system and pressure check/fix any leaks. Confirm fluid levels, condition. Then start and warm the motor, any off sounds, is it missing, setting code(s), consuming water, etc?

 

[BILT4ME]

My evaluation would be: Check for codes. Fill the cooling system and pressure check/fix any leaks. Confirm fluid levels, condition. Then start and warm the motor, any off sounds, is it missing, setting code(s), consuming water, etc?

With what he described, I would pull the plugs and turn it over after filling with coolant so it doesn't hydrolock.

 

[cowboyjack]

“I plan on keeping it for a loooong time. So, if you were me, or youd had to do yours again, would you pull the lower pans to check and make sure everything looked OK? Would it have even been obvious anyway had you checked things out down there?”


Things looked fine when we pulled the head so don’t know that I’d have done anything different.

Playing the percentages, just redoing the head has worked for lots of mudders and it’s what I did.

Loose nut was pretty random and just plain bad luck. We didn’t find it until engine was out of the vehicle and had the upper oil pan off.

 

[LINUS]

Consider a V8 swap. If you need to have toyota parts look for a good 4.7 litre, if not look for a good 5.3 or LS.

Part out motor, or sell as a donor/rebuild to recoupe some costs.

If GA emissions are loose like alot of places, I’d consider this too if you have the talent to DIY the majority of work.

LS’s are great motors, but IMO a 5.3 is more practical unless you want to do axles too at some point.

I’ve got a LS3 and it made my jet sled a new animal upgrading from a Vortec 350.
It pops up on step like a corky when you snag the leader, zero lag.

 

[cody c]

If GA emissions are loose like alot of places, I’d consider this too if you have the talent to DIY the majority of work.

LS’s are great motors, but IMO a 5.3 is more practical unless you want to do axles too at some point.

I’ve got a LS3 and it made my jet sled a new animal upgrading from a Vortec 350.
It pops up on step like a corky when you snag the leader, zero lag.

Yeah. I'm not in love with the 5.3 or the LS's, but the 5.3 has a good reputation, it isn't overly heavy and has acceptable power output.

The LS's, well to be honest I'm making the suggestion for a matter of keeping weight down, or even improving as compared to the 3FE or 1FZ. My 6BT is not light, and after having a TBI 350 in place of a 3FE (previous to my 6BT) I can see how more nimble an 80 series can be.

I like the idea of an aluminum block V8, reasonably torquey / efficient and reliable. I guess there are some lexus donors too, though maybe not really torquey.. (1UZ-FE) edit: had to look it up, about 220lbs lighter than the 1FZ

running donors can be found for a decent price too
1996 Lexus LS | eBay

but Im not sure about adapters and all that.

 

[bob82pigdog]

As much as I love, and honestly prefer the idea of a V8 swap (I would do a GM), it will take way more time, and more money. I just don't have the bandwidth right now for a project of that scope. I have two other project cars, two young kids and an old house all vying for my attention. The tear down and rebuild of the head I can manage at the moment.

However, if I get in there and it looks like the bottom end has issues, I will not spend the $$$ to rebuild the stock motor. I'll just park it and save up and gather parts for a V8 swap. Or find a suitable donor motor from another 80. Hopefully this will not be the case! Wish me luck! I'll report back if anyone is interested, but it'll be a few weeks. No car projects for the holidays!

What has your oil pressure been to date?

Unfortunately for me, I have no idea. Gauge and/or sender has never worked since I Have owned it.

 

[BillyGoatMTB]

Bump

Morning Mud

@bob82pigdog how did it turn out?

I have my 1fz torn down forehead gasket and had the head redone. I wasn't comfortable with the timing chain tensioner not feeling solid so I tore out the oil pans and the timing chain cover I'll be replacing everything with fresh Mr T parts.

I'm asking because the block is still in the truck I'm considering pulling it for a full rebuild but before I tore it down compression was amazing and my black stone oil reports showed no bearing wear. I thought today at least pull a few rod and pissed and bearing caps and have a look.

To rebuild the bottom or not to be rebuild the bottom...... Where's the line for rebuilding the bottom end. Again I had fantastic compression and my Blackstone oil pork don't show any bearing wear.

Also I thought my cylinder walls looked fantastic photos attached.

I'm glad I followed my gut and pulled the timing chain cover because the fpig and o-rings were completely rotten I don't think they've ever been taken apart. At some point the upper oil pan have been off because someone used gray art TV that had basically turned to powder when I was removing the bolts.

My current plan is valve job new valve seals (complete), only time and components, Master head gasket kit, fresh and oil cooler, new radiator, new hoses, New belts, new factory wiring harness, new plugs of course,

Thanks for the input