I just started the job of changing my motor mounts and to my horror, discovered that two of the bolts that hold the motor mount bracket on the passenger side of the block were missing. Only the top of the triangular bracket has a bolt. So now I must remove what is left of the other two bolts that protruded from the block. Are these double sided bolts that are screwed into the block? What is the method to remove these? I haven't removed the bracket yet to see if they are broken flush with the block or even deeper. Any suggestions welcome. I wonder why they didn't use regular bolts on these brackets rather than having bolts protrude from the block?
PV444--B16

reverse drill bits have been saviors to me many a time

Good luck with their removal.
For convenience I can see no reason why you shouldn't use correctly spec'd and sized bolts plus split lock washers as replacements. They will always want to spin outwards as you undo up the nuts. Loctite would help but I can't see Volvo's reasoning for doing it like this. The parts book does show the studs to have a unthreaded centre section and probably have a coarser thread on the block end.

Success! I used left handed drill bits and a "close quarters" drill to get at the broken studs. With the first stud, that was all it took. It started to turn as I got a bit into it and was then able to grab the end with vise grips to remove it. The second stud was a bit more troublesome. I did the same routine but then used a small screwdriver jammed into the hole to twist the bolt out. I guess an easy out would have done the same thing here but I didn't have any of those handy. Eric was correct in that the hole goes right into the crankcase so that oil kept the bolts from freezing/rusting up. I have the bracket back on. I used two metric bolts to replace the missing studs. The size is M8 X 1.25 (20mm length was the length that seemed closest to the stud piece plus some extra for the bracket and lock washer)in case anyone needs those numbers for future use.
Harbor Freight sells a handy spring-loaded center-punch that you just push against the broken stud to make the starting drill point, by the way.

Thanks to all for your suggestions/help. Ken

I have a B18 so maybe not applicable but the mounts are fastened with three ordinary bolts. If the broken ends protrude, you can try a vice grips. I have had no luck with easy outs. I have had very good luck with welding another bolt on the stub that is left and backing out that way (even when broken flush with the block, this works well).

The nuclear option is to carefully drill with progressively larger bits till you get near the root diameter of the bolt and then use a pick and tap to clean the rest out. Or drill one size bigger and use a helicoil, but i believe you would have to yank the engine to do these.

good luck
dean

http://s1086.photobucket.com/albums/j444/Kielbalsa/motor%20mount/?action=view¤t=withbracket.jpg#!oZZ1QQcurrentZZhttp%3A%2F%2Fs1086.photobucket.com%2Falbums%2Fj444%2FKielbalsa%2Fmotor%2520mount%2F%3Faction%3Dview%26current%3Dbracketoff.jpg


Here is a photo of the side of the block with the bracket removed. As you can see, the studs are in there but recessed in the holes. I guess it's the drilling option now.

Oh that aint a pretty sight. I would still try to tack weld a small bolt on to that broken piece. Since it is not a blind thread, there is a good chance the oil in the crankcase has kept that bolt from rusting in place. Actually in this situation, maybe an easy out would work ok.
Dean

Yeah, I didn't see that when I bought the car. The generator was in the way. At least the motor didn't fall out of the car like some Laurel and Hardy short.
I'll report my results when I have any.

As Dean said, see if there is some bit of the bolt you can try and grab it. I would spray it down with penetrating oil before tried with the vice grips.

I also have had limited (to very limited) luck with easy outs. I have pulled out many more broken bolts via welding a nut on what every is there. The only think to add to Dean comments is that I often weld the nut on (sometimes I put a small washer on first and weld on a larger nut) and then spray the area with penetrating oil, it cools it down and the oil gets pulled into the threads.


Chris

Hello,

HOLD ON!!

The stock mounting hardware to hold B16 motor mount brackets to the engine are metric studs and nuts.

So all you may need to do for now is install new nuts and lock washers.

If you decide to change the studs, be aware that the threaded holes for the studs are not blind and go through to the inside of the crankcase.

So use some thread sealant to prevent oil leaks.


--
Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90502

OK, thanks for the info. I will take the bracket off and see what is there. I think the studs are flush with the block if not deeper because I poked a screwdriver into the holes of the two missing studs. There's nothing to put a nut on to. Hard to believe the engine has been held into place by one small stud all this time.