Broke 4 bolts in my 401 engine?

This sounds like an ugly one-been there. You are going to need a 1 1/8" socket to get the crankbolt off. It's going to be very tight and I rig up my breaker bar with a pipe extention to get it wedged at the frame and then 'bump over' the engine with the starter to pop it loose. I generally use propane to heat alumunum covers such as this. Soak and heat and wiggle and pry and pray....take your time-you'll get it-might need another cover in the end, but they're around-good luck!

 

be double sure you use anti seize compound when you put it back together.....:Brow: :Brow:

 

I have used so much WD40 trying to loosen rusted bolts that they should send me a prize. All WD40 is for is to lube moving parts, and prevent rust. PB Blaster and Liquid Wrench or similar is for penetrating into rusted spots that need freeing up. It moves slowly thru rust, but it moves. Gently tapping the bolt moves the bolt ever so slightly, and allows the penetrant to move further in. After a while, theoretically, the entire bolt's threads should be wet with penetrant, which at this point is going to act as a lubricant to aid in finally being able to turn the rusted bolt out. Heating the metal containing the female part of the fastener (like a nut or block) makes it expand ever so slightly to help break the bond between bolt and hole. (Hope no mods are reading this--I might get busted for using terms like female, nut, hole, lubrication, penetrant...No wonder guys like cars! ahem) Anyway, you get the idea for use on future rusted fastener issues. :bglasses:

 

After reading your dilema, I have to agree with buick64203 and just replace the front cover or timing cover as it is sometimes called. Starting with a new part will ensure no further problems when you install the new water pump. Its more work but a much better end result.

 

Did the timing cover bolts turn at all before they broke? If not, the heads may have twisted right off without moving the bolts at all.

Here's the bad news you did not want to hear - the bolts are PROBABLY frozen to the timing cover. This happens with steel and aluminum, and it might mean that you will have a tough time prying the cover loose without wrecking it.

This is a place to go slow and work on maintaining your cool. Worst case would be to haul the car to a shop and let them deal with it - remember that IS an option.

I went through this, and I solved it myself but only had one bolt stuck in the cover. I was able to get the rest out, and I finally ended op rotating the entire cover like a wrench to get the bolt out. I was then able to heat and soak the bolt and drive it out on the bench.

One recommendation - try Aerokroil penetrating oil. It's much better than PB Blaster and really works with a little heat and waiting a day or so after squirting it on. You get get it on Amazon online of all places.

Good luck -

 

The condition mentioned above is very likely.
Which bolts broke exactly? Do they have 7/16" heads or 1/2" heads? The smaller 7/16" head bolts will be short and won't pose a problem removing the cover. The 1/2" head bolts go through the cover into the block. The dissimilar metals on the aluminum cover and the steel reacts and oxidizes causing them to seize bad. Rarely do these seize where the threads go into the block on the long bolts. Its almost always the bolt to the aluminum whether it be the short threaded bolts or the long smooth part of the bolt shaft that passes through the cover into the block.

So, if the 1/2" head bolt(s) broke, removing the timing cover can be very difficult because it usually requires prying on the cover somewhere and aluminum is easily damaged.

If its just the little 7/16" head bolts you won't have a problem removing the cover. If you remove the cover, you'll need a timing cover gasket set and while its off if the timing gear has nylon teeth replace the chain and gears as well.

Also good to know....the cover is pinned to the block so it must come straight out about 1/4" before it will rotate to try and wiggle it off the broken bolt.

The right amount of heat, penetrating oil plus patience is the best combination.

 

What I did in this situation was to take a very small drill and drill in from the side of the bolt boss in the timing gear cover untill I felt the bit hit steel instead of aluminum/corrosion..... then I took a needle and sryinge and injected some atf several times over and heated the area with a heat gun....

 

Thank you gentlemen. I haven't tackled the riv timing cover yet because of how I've been working. I broke two of the smaller bolts and 2 of the 1/2" bolts. I think they are broken in the cover if my memory serves me correctly. I damn sure hope they are. I'm currently looking for a replacement cover because i think this is gonna get really ugly. The bolt that holds down the alternator bracket was almost completely out when it broke. This bolt has some of its threads showing.

 

pb blaster or 50/50 atf/acetone mixture,,,, what I do with those really stubborn ones is to take a very small drill and drill in from the side, right where I figure the threads are and then take a needle and srynge and squirt the mixture in the drilled hole....and let it soak for an hour....and use a heat gun....

 

Turns out they were not broken in the cover and only one was broken in block. About half an inch. I gonna attempt to remove this today. Good news is i dont need another timing cover. Another lesson i learned is do not use bolts from home depot!! They are cheap and made of zinc?

thankks again

 

It makes sense but the alternator bracket bolt also screws into the block so even when you take the cover off you still have problems. hopefully the bolt will be stick out of the block and you can get a hold of it. Good luck

Bob H.