Cracked Block 1FZ-FE (1 Viewer)

[Ppleasants]

Last year I noticed a crack in the engine block of my 94 FZJ80, just below a driver's side freeze plug. It's an almost identical issue to the one noted here: Leaking Freeze Plug

The above thread fizzled out with no real solution so I figured I would start a dedicated thread to this issue. If anyone has seen something similar, please share your experience, repairs/solutions, and any other insights that might be helpful. I understand the most thorough solution is to swap out the block or entire engine but that's not really feasible at the moment... so below documents my attempt at repair and current failed state.

It's hard to tell the orientation from the photos but the crack runs vertically from the center of the freeze plug hole down about 1.5 in. Note the PO's attempt at a "fix" (cover the whole thing in silicone) that was definitely not disclosed upon selling...

I drained the block, removed the freeze plug, and cleaned the crack and surrounding area thoroughly with brake cleaner. I then ground out a shallow V notch along the crack and tried to stop-drill the end. I filled the crack with JB weld and cleaned off excess inside the freeze plug hole. I installed a new freeze plug with the appropriate sealant (not JB Weld). This fix held up for about a year until I just recently noticed that I was leaking coolant again.

I don't have a current photo showing the leak but will be cleaning and inspecting the area soon. The leak appears to be coming from near the freeze plug, not further down the block. I'll likely remove the freeze plug, clean everything again, and maybe grind off the JB Weld and reapply.

 

[shocktower]

You could have someone braze it or TIG weld it by a professional or do the JB thing again

 

[slow95z]

if you end up wanting to swap it out let me know. i have used engines.

 

[Pin_Head]

Repair it permanently with stitching pins. Google Lock-n-stitch.
Your local machine shop can do it or you can buy the tools and do it yourself.
Whatever you do, don’t weld on it or even heat it above 1,200 F.

 

[BillyGoatMTB]

Bump
Afternoon MUD

I noticed the same issue today on my 1997 1fz.

Any reports of catastrophic failure from this?
Or, sucess with stitch pins?

I'm thinking about running with it for a while and just keep an eye on it.

I take the family on Forest adventures so if there's any risk of catastrophic, ill use a different vehicle.

the previous owner was honest with me about it overheating from a blown pesky heater hose so I figured when the time came I would just go to the new factory Short block but I'm not quite ready for that yet.

Thanks MUD

 

[Ppleasants]

Bump
Afternoon MUD

I noticed the same issue today on my 1997 1fz.

Any reports of catastrophic failure from this?
Or, sucess with stitch pins?

I'm thinking about running with it for a while and just keep an eye on it.

I take the family on Forest adventures so if there's any risk of catastrophic, ill use a different vehicle.

the previous owner was honest with me about it overheating from a blown pesky heater hose so I figured when the time came I would just go to the new factory Short block but I'm not quite ready for that yet.

Thanks MUD

View attachment 2413927

View attachment 2413929

Hey @BillyGoatMTB, this is the thread I started when the other one went silent. Maybe someone else will chime in here if they've had any different experiences.

 

[Pin_Head]

Stitching pins have been used for this type of crack for over 100 years, so it is known to work.

On the other hand, that is a minor crack and leak, so Bar’s leak or Blue Devil block sealer would work. Probably for the lifetime remaining on the engine.

 

[BillyGoatMTB]

Stitching pins have been used for this type of crack for over 100 years, so it is known to work.

On the other hand, that is a minor crack and leak, so Bar’s leak or Blue Devil block sealer would work. Probably for the lifetime remaining on the engine.

Awesome
Thanks MUD!

sounds like it's NOT an emergency and I can keep going on trips and explorations for an extended period of time while monitoring this?

my cooling system is 100% brand new other than the radiator I've had the truck for a year and put about 250 hours of work into her.

Maybe I should go with the bars stop leak or blue devil which do you prefer?

Run her for a while, drain the whole system and put in a new radiator?

Thoughts?

 

[Ppleasants]

Awesome
Thanks MUD!

sounds like it's NOT an emergency and I can keep going on trips and explorations for an extended period of time while monitoring this?

my cooling system is 100% brand new other than the radiator I've had the truck for a year and put about 250 hours of work into her.

Maybe I should go with the bars stop leak or blue devil which do you prefer?

Run her for a while, drain the whole system and put in a new radiator?

Thoughts?

FWIW, the local Toyota guru here in CO (everyone in the local club recommends him and he's usually booked up) said to try Bar's Leaks. I have it sitting on the shelf but just haven't tried it yet.

I've taken my 80 up mountain passes and down forest service roads without any issue. Not to say that something COULDN'T happen but the crack in the block is low down the list of things to worry about - it's only on the water jacket.

 

[BillyGoatMTB]

FWIW, the local Toyota guru here in CO (everyone in the local club recommends him and he's usually booked up) said to try Bar's Leaks. I have it sitting on the shelf but just haven't tried it yet.

I've taken my 80 up mountain passes and down forest service roads without any issue. Not to say that something COULDN'T happen but the crack in the block is low down the list of things to worry about - it's only on the water jacket.

I'll monitor for a bit. I may try Bars then replace radiator with full coolant replacement. I have heard the coolant stop leak products can be rough on radiators.

How long has yours been cracked and leaking?

 

[Pin_Head]

The modern block sealers don’t gum up things the way the products your grandfather or dad told you about 50 years ago.

Be sure to get the right product. They both make several different types of sealers for different situations.

 

[BillyGoatMTB]

The modern block sealers don’t gum up things the way the products your grandfather or dad told you about 50 years ago.

Be sure to get the right product. They both make several different types of sealers for different situations.

Excellent point and yes Dad was very against coolant fixes in a bottle.

Any recommendations for our 1fz cast iron blocks? Bars makes a coolant system repair?

 

[Pin_Head]

I would use Bar’s 1111 permanent block sealer and head gasket repair because it is antifreeze compatible. Blue devil makes something equivalent.

 

[SNLC]

New short block from Toyota for about $3600. Or find a good used one which is getting increasingly difficult.

Or, put a bandaid on it and drive it till it dies.



Cheers

 

[BillyGoatMTB]

For those of you with this hairline crack by the block train there's also part of a conversation I'm having in this thread.

Looking for a 1FZ Long Block? New/Rebuilt

Do a brass 3 core radiator from Beno and never worry for years to come.

forum.ih8mud.com

I'll post back with the direction I decided to go. So far @BILT4ME suggestion rings the clearest as the best choice to try first, which is, replace the freeze plug, while open apply penetrox number two sealant all around the crack inside and out, also applied all over the new freeze plug, Scotch-Brite the freeze plug hole and reinsert.

Since I cleaned it up I've had zero leakage. I'm questioning if the one time at leaked was a few weeks ago on a family trip over 6,000 ft where my radiator was boiling over into my reservoir, not sure what happened but I replaced the radiator cap with a new factory cap, the old one was a new Toyota factory as well but I heard sometimes they're bad.

Maybe that pressure caused it to leak for the first time?

 

[Ppleasants]

For those of you with this hairline crack by the block train there's also part of a conversation I'm having in this thread.

Looking for a 1FZ Long Block? New/Rebuilt

Do a brass 3 core radiator from Beno and never worry for years to come.

forum.ih8mud.com

I'll post back with the direction I decided to go. So far @BILT4ME suggestion rings the clearest as the best choice to try first, which is, replace the freeze plug, while open apply penetrox number two sealant all around the crack inside and out, also applied all over the new freeze plug, Scotch-Brite the freeze plug hole and reinsert.

Since I cleaned it up I've had zero leakage. I'm questioning if the one time at leaked was a few weeks ago on a family trip over 6,000 ft where my radiator was boiling over into my reservoir, not sure what happened but I replaced the radiator cap with a new factory cap, the old one was a new Toyota factory as well but I heard sometimes they're bad.

Maybe that pressure caused it to leak for the first time?

The first time I noticed mine was when I accidentally bumped the shifter into neutral on the interstate and the RPMs spiked for a second. Could have been completely unrelated but I saw steam and after investigating, I found the leak and previous repair attempt.

Curious to see your results. I‘ve used a product called Captain Tolley’s Creeping Crack Cure to seal up seams on my Airstream. I was wondering if there was something similar for an application like this - a water-thin creeping sealant. I’m planning to tackle a re-repair on mine soon and might try your method.

Are you referring to Permatex form-a-gasket?

 

[BillyGoatMTB]

The first time I noticed mine was when I accidentally bumped the shifter into neutral on the interstate and the RPMs spiked for a second. Could have been completely unrelated but I saw steam and after investigating, I found the leak and previous repair attempt.

Curious to see your results. I‘ve used a product called Captain Tolley’s Creeping Crack Cure to seal up seams on my Airstream. I was wondering if there was something similar for an application like this - a water-thin creeping sealant. I’m planning to tackle a re-repair on mine soon and might try your method.

Are you referring to Permatex form-a-gasket?

Yes, permatex form a gasket is what built for me suggested in the thread I attached in my previous reply it makes a lot of sense.

with the correct radiator cap and the cooling system only supposed to get up to 13 PSI replacing the freeze plug and using permatex makes a lot of sense.

I know I'm old school influenced by Grandpa and Dad I'm just nervous to put stuff in my cooling system.

I prefer to replace the freeze plug anyway no telling how much coolant worked its way around the seal.

I think today is day 4 daily driving zero leakage.

Hey at least she's easy to keep an eye on right just look straight through the wheel well

 

[fj80pb]

Hi there!
I'm having this exact issue with my 97'. Your pics are identical to mine. With a cold engine the hairline crack is virtually invisible
I first thought the freeze plug was the culprit, so I replace it. See my post on the matter here:
FREEZE PLUG HELP . Only to discover the real culprit was that hairline crack in the first place.
I have used Permatex # 1 to seal the new FP with the block (thanks @BILT4ME for the hint) . Once the engine is warm, I can now see how the red coolant is slowly dropping trough the small crack...not much....but a leak is always a leak and my OCD can't handle that.
I'm very curious to learn what method has been be the most frequent and successful in dealing with this hairline crack:
a) Bar's 1111 or similar product
b) JB Weld Extreme Heat or similar
c) New FP but this time with a dosage of Permatex # 2 from the inside out the FP whole and crack
Taking the engine out to perform a stitch weld seems, given the minuscule crack, quite extreme and worst-case scenario...but...one never knows. And a new short block would be an overkill, isn't it?
I have read these threads but, so far, I have failed to read a common or most frequent recommended solution for what it seems to be a new theme with our rigs:
Leaking Freeze Plug
Cracked Block 1FZ-FE
By no means is a widespread event....as of yet. However, it appears this crack is becoming a new recurrent issue in most 1FZFE engines-after all they are over 20 years old.
Do you think this qualifies to be added to the FAQ section under the “Hairline Block Crack” label, or similar?. IMO, it will help fellow mudders in finding a consistent approach
I would appreciate knowing what the MUD community has done in the past with this issue and what's the most common process to address it.
Thanks!
Cheers!

 

[Axe 44]

I noticed this same crack 7 months ago on my 93 with 240k miles. Started out thinking it was just the freeze plug, but then saw the crack. I read all I found on Mud and ended up just using CRC K&W Block Seal based on a recommendation I read. Followed all the instructions which included a 24 hour curing period. It leaked again immediately. Decided to just go with it since it wasn't losing much coolant. Maybe 8 ounces a month pulling a 3,500 lb. construction trailer most days. 6 months after noticing the leak I drove 3,500 miles out to CA and back for a job. There was a heat wave and lots of gradual grades. Seems like the leaking has gotten a little worse since that trip. I can't tell if the crack is growing, but smelling more coolant while driving. Coolant doesn't seem to make it to the ground before evaporating on the hot engine.

This pic is how it appears now (7 months after finding the crack) while being used as a DD.

I'll likely try the permatex/freeze plug fix next. I'd consider the stitching pin repair recommended by Pinhead, but it's a bit of money for a high mileage motor.

 

[BillyGoatMTB]

This is starting to look like a trend. I wonder what it is about the manufacturing defect? I also wonder if the new factory short blocks are prone to the same casting and/or engineering defect.