External cracked cylinder head - Leaking oil! (1 Viewer)

[NorCalFJ100]

Okay everyone, I have a new motor with about 2,000 miles on it. Everything seemed to be going fine. Motor was rebuilt by a reputable shop...head was rebuilt by someone who I thought was reputable. Now I do not really think this crack is something that could've been avoided. Just bad luck really. However the head was supposedly pressured tested.

I noticed this leak about a 6 weeks ago. I would clean it up and each time I felt like I saw a remnant of oil leaking past the valve cover gasket. I used a new OEM for the original rebuild. I automatically assumed it was an issue with the gasket or a slight imperfection in the head. Finally got around to pulling the cover. Everything looked perfect. To be safe I put a small bead of Toyota FIPG. Let it dry for a bit. Reinstalled and let it sit for two days.

Took her for a test drive tonight...opened the hood and BAM! Leaking again!!! Upon a more intricate investigation, the use of a strong LED light and mirror I uncovered a very small crack. So small you cannot see it really. Just the oil slightly bubbling when I increase the rev, from this area in red below. There is a crack visible from the top, but it for sure is not leaking from this site...at least not anymore after my gasket repair.

Has anyone used any JB Weld type products to fix things like this? I have been researching google and it appears there are quite a few different products. I am thinking I clean this area up with a brass brush, maybe a little sandpaper and patch it up. Besides the pressure of the oil, it's not subjected to anything else.

Amazon product ASIN B01ID9M8JK
Amazon product ASIN B007PP26RI
What are your thoughts?

 

[scottryana]

I think you would be totally fine patching this with JB Weld. It isn't under pressure. You would just need to make sure it is cleaned really well.

Okay everyone, I have a new motor with about 2,000 miles on it. Everything seemed to be going fine. Motor was rebuilt by a reputable shop...head was rebuilt by someone who I thought was reputable. Now I do not really think this crack is something that could've been avoided. Just bad luck really. However the head was supposedly pressured tested.

I noticed this leak about a 6 weeks ago. I would clean it up and each time I felt like I saw a remnant of oil leaking past the valve cover gasket. I used a new OEM for the original rebuild. I automatically assumed it was an issue with the gasket or a slight imperfection in the head. Finally got around to pulling the cover. Everything looked perfect. To be safe I put a small bead of Toyota FIPG. Let it dry for a bit. Reinstalled and let it sit for two days.

Took her for a test drive tonight...opened the hood and BAM! Leaking again!!! Upon a more intricate investigation, the use of a strong LED light and mirror I uncovered a very small crack. So small you cannot see it really. Just the oil slightly bubbling when I increase the rev, from this area in red below. There is a crack visible from the top, but it for sure is not leaking from this site...at least not anymore after my gasket repair.

View attachment 1925313
View attachment 1925314

Has anyone used any JB Weld type products to fix things like this? I have been researching google and it appears there are quite a few different products. I am thinking I clean this area up with a brass brush, maybe a little sandpaper and patch it up. Besides the pressure of the oil, it's not subjected to anything else.

Amazon product ASIN B01ID9M8JK
Amazon product ASIN B007PP26RI
What are your thoughts?

 

[NorCalFJ100]

I think you would be totally fine patching this with JB Weld. It isn't under pressure. You would just need to make sure it is cleaned really well.

This is what I am thinking. I guess worst case it doesn't work. No harm in trying.

 

[TomH]

Some more info here:

Hairline Cracks In Cylinder Head -- Advice Please!

Greetings, first off great site and forgive me if this issue has been covered. I recently bought a locked '96 with 73K miles (!!!) on it. Truck runs great, no problems, no rough idle, no power loss. The previous owner mentioned he'd replaced the head gasket. This seems to be pretty typical...

forum.ih8mud.com

I used fipg on mine and haven't had a problem.

 

[NorCalFJ100]

Some more info here:

Hairline Cracks In Cylinder Head -- Advice Please!

Greetings, first off great site and forgive me if this issue has been covered. I recently bought a locked '96 with 73K miles (!!!) on it. Truck runs great, no problems, no rough idle, no power loss. The previous owner mentioned he'd replaced the head gasket. This seems to be pretty typical...

forum.ih8mud.com

I used fipg on mine and haven't had a problem.

Guess this is a somewhat common issue. Definitely going to try JB weld or something similar. Thanks for the help!