Need Assistance - Valve Cover

I'm in the process of replacing the valve cover gaskets. I have the parts, began the work on the passenger side at 8:15 am this morning. Murphy is helping me. So far, I have a broken bolt, rust. The one directly above the exhaust manifold.

Current problem. All bolts/nuts removed. Valve cover will not let go of the engine. Any tips to release the grip???

The broken bolt, I hope to be able to remove once the valve cover is removed.

Looks like I'm going to make a trip to Toyota for a set of valve cover bolts and nuts. The condition of the bolts/nuts is poor. Gotta love the salted winter roads of the MidWest coupled with 115,000 miles of minimum maintenance.

 

C'mon guys........I'm fighting with Murphy and he is winning.

The valve cover appears to be hung on the 3 bolts on the low side above the exhaust manifold.

I've earned a few bloody knuckles using a utility knife to "cut" the RTV at the timing cover/head interface......

Still no budge. I'm resisting wedging my wrecking bar, used for home demolition, to force the cover.........but my rope is getting short.

 

You removed all the coils as well correct?

 

Yes. No bolts, nuts, fasteners, coils........just valve cover. All has been removed. Cover won't budge.

 

I've never had one stuck that bad, usually can pry them off gently with a screwdriver but then again I'm not in the rust belt.

 

Thanks..

A sarcastic comment may inject some humor.

Right now, I'm wedging utility knife blades into the gap with tapping for force.......

Sent the Daughter to Toyota to order new bolts and nuts for this task. Of course, not in stock, be here tomorrow.

 

ok......I may have I found the problem........

The "clearance" hole around the 2 studs (nuts) are not clear. They appear to be filled with........corrosion. This is locking the cover into place.
Steel bolt + aluminum cover + brine + heat cycles = galvanic corrosion.

PB Blaster isn't touching it. I'm thinking either my propane torch to heat the cover around these studs or try a chemical rust remover........

Thoughts? Comments? C4?

 

Been there with my 2 lb dead blow hammer. Keep the thoughts coming.


The friggin' clearance holes around the studs appear to be full of corrosion.

 

Ah iron and aluminum, always fun when those get stuck together
Heat can help break the bond, do the studs have socket heads on them that you can use to try to turn them?

 

Heat, PB, and a hammer would be my suggestions.

 

Woooooohhohhhoooooo......

Got the front stud loose. Propane torch was the key.....

Now to tackle the rear stud near the fire wall.

 

Ah well quicker than my post, but for future reference.

Get some computer dust off, the cans of compressed air. Turn can upside down and blast the liquid on it for a several seconds. Flashes off at about -50F. Less chance of damaging parts or starting your truck on fire. Then you will have to give it a little tappy tap tap.

https://youtu.be/rljUld-ptvI

 

Small problem with "freezing". That process will shrink the clearance hole, making the fit tighter.

Heat will expand the aluminum, making the hole bigger. This should break the grip of the corrosion.


Yes, I am extremely careful with a propane torch. There is a very busy grounding stud near this location. All the flame is directed away from the wiring or other nearby combustables or explodeables.....

Gonna break for a sandwich......then back to it. Glad I planned all weekend for this task......criminy. Why is nothing easy?????

 

Thanks all.

Success. The valve cover is off. Only took 6 hours. Damn corrosion. Doing clean up on the valve cover, then clean up the head gasket surface.

Should be downhill from here on the passenger side.

 

Sometimes a valve cover will have a tab on the edge to tap on. You can use a gasket scraper to tap straight in between (do not pry) the valve cover and the head. Work on one end and then the other end, rinse and repeat. If you mar the surface you can take a small, fine, flat file and file the bur down a teeny bit. .

 

why do certain states use salt

MAP gas > propane
high quality penetrant > low quality
MAP can also damage or deform weak metal if not careful

gaskets can get stuck. Sometimes freeing things requires gentle tap with rubber/plastic deadblow hammer and/or careful prying.
As opposed to not careful.
Like if you bashed on it with metal hammer and pryed indiscriminately. It would get dented and gouged/unable to seal.

 

A bit of follow up.

So far, I've only addressed the passenger side. Valve cover is Off. The corrosion in the clearance holes around the studs was locking the cover in place. A combination of heat, prying and cussing managed to release the cover. There was no space around the studs to use a pick. No tabs to pry against. Very little room to swing a 2 lb dead blow hammer, couldn't generate a solid impact.

Began the clean-up on the cover. Used a series of drill bits to clear the corrosion from the all bolt/stud holes. A spray of Throttle Body cleaner cleared the grooves for the gasket. All aluminum corrosion has been removed from the mechanical surfaces. Cover is set for install.

The head has a broken bolt that needs to be removed. This is the bolt directly above the exhaust manifold, between the 2 corrosion locked studs. At this point, I've wrangled about 1 full thread out .... still very tight. Not much stub to grip. My vise grips are too big to manipulate very well in that area. Heat and PB are the influence working this out. Once the broken bolt is out, then I can clean up the gasket surface on the head.

Tomorrow, I'll be stopping at Toyota to pick up my order of 14 bolts and 4 nuts. Then to the local tool store for a smaller pair of vise grips. My big 10" is just too much for that small space.

I'm considering a metric tap & die set. I'd like to be sure the threads are clear. My plan on reassembly is to use a touch of anti-sieze and to pack the clearance hole around the studs with grease. Hopefully, the next schmuck won't have such a difficult removal.

This job isn't complex, but it has become a giant PITA due to corrosion related issues.

 

tap and dies are not for cleaning threads
they are for removing metal

thread restorers are