Help - cracked engine head OMG I think I just ruined my wife's car!

You've put a bit of a hole in the valve cover. Since you likely don't have an extra valve cover laying around, what I would do, based only on the photo, is carefully fish out the broken piece, (assuming no other pieces fell in) clean the area very well, fabricate a small piece of metal/tin/whatever that would cover the hole. Mix up some JB Weld and us the previously made patch to cover the hole. Just don't go crazy with the JBW. Don't want any dripping into the engine. Start looking for a replacement valve cover. Should be plenty out there on ebay/etc.

 

EXACTLY! Just "glue" it back in place. You will NEED to clean the area with brake-parts cleaner and a rag first, to get the oil/grime residue off first, but this is not a real problem, unless the piece drops in. If that happens, you will have to remove the cover, fish out the broken piece and might just as well replace the cover and gasket.

 

I haven't used JB weld, but you might want to check that whatever adhesive you use is intended to do metal-to-metal bonds, and is certified to withstand the temperatures reached by the engine block. I would also consider using Permatex Form-A-Gasket (the hardening, non-flexible version) as it is designed to work between clean metal surfaces and hold at the normal operating temps of an ICE. I totally agree that finding the piece , cleaning it, and prepping the surface is key to having a successful bond of the broken piece back onto the valve cover.

 

This has been reported at least twice before that I can recall. The peril of using anything other than a (deep) socket to bust it loose, and yeah: JB Weld has worked before, it's just the valve cover. It's an aluminum casting? Stamped steel would maybe have been better, and/or a bit more clearance.

 

Made a little sketch:

 

Most of the time JB weld is not going to hold long term. So source a used valve cover and new valve cover gasket while it's still holding.

GOOD LUCK

 

Open-end wrenches make one H#LL of a powerful lever! You bust locks with them!

 

Oh...my....god....

Blasphemy!!!! How dare you doubt the power of JBW!!!!!!! Unforgiveable......



Of course, now that I said that, it will probably fall off tomorrow morning....

 

LOL!

Yeah, it doesn't bond well with surfaces impregnated with oil or solvents unless thoroughly, thoroughly cleaned on both sides. In the motorcycle world, it's good band-aid for cracked or holed engine side cases/covers to get one home but not a permanent solution.

 

New prices, for reference and parts numbers. Item 3, and might as well get the item 4 (gasket):

Engine for 2007 Toyota Prius | Toyota Parts

 

You could get away with using a wrench, if you kept it up near vertical, but you're playing with fire, lol.

 

A less expensive option:

2007 PRIUS VALVE COVER 218882 | eBay

 

Someone has some spare time on their hands.

I can tell what you used to do in a working career.

Well drawn example.

 

AutoCAD sells for god knows what these days, 2~3 grand. And a lot of the big engineering companies have shifted to other programs, more conducive to 3D modelling. I would check on their model, then play around with my acad, splishsplash in the shallow end. Enjoyed it.

 

Once had a CB400A parked between two vehicles, someone with a tow hitch backed into it and left a broken 'H' shape in the engine cover before eventually knocking it over.

Took the cover off and cleaned the surface (don't remember prepping it with sandpaper or wire brush, but might've), taped/plugged up the backside, made a small berm around the broken H (hole) on the front side, mixed up the JB, filled the hole, let it set up for a bit, then stuck it under a spot lamp for a quicker cure time (didn't want to wait for hours/overnight).

A quick and easy fix that lasted for years, though there was some sweating via the 'pores' in the JB patch (never enough to form a drop), but it did make it look lightly sooted over a period of time.

 

Yes, you need to change the valve cover gasket. Also, you need a small amount of Toyota black FIPG (form in place gasket) which is used to seal two places where the oil pump/front engine cover contacts the cylinder head and the valve cover.