Missing main cap bolt.

[MrSony]

Hey all. My SBB seems to have a main cap bolt that is missing. I have 9/10 which as you can imagine is very irritating. The last thing I need is to spend 100$ on NEW fasteners, then turn around get the block off of the stand again, and have the mains align honed for another 100 or so, when money is already tight.\ (Working on a 7.25/hr budget here.) I really do not want to have to go through all that. Would I just be able to get some old/OEM bolts off of ebay or something and use those without issue if I can't find the missing bolt? ALSO, how do I know what order the caps go in on a 1977 Buick 350? It's obvious for the front and rear, but the three inners I have no idea. This engine will not make over 300hp to the crank. Not a high spec runner, just a mostly stock rebuild. Slightly better cam, bored 30 over, heads being cleaned up, etc.
Any help is appreciated.

 

[pontiacgp]

If the caps are not marked as to where they go then unfortunately you're going to have to get them honed. If you check with an engine builder they will probably have a main cap bolt.

 

[MrSony]

on the tops of them there are 11, 12, and 14 from what I remember are on the inners.

 

[MrSony]

on the tops of them there are 11, 12, and 14 from what I remember are on the inners.

Could I use studs instead of bolts? Would that be sufficient, or would it still need honed?

 

[pontiacgp]

the block needs the be marked as well the same as the caps. I always number them with dimples if I don't have number stamps. You can use studs but you need to have the bore in the caps lined up perfectly or the engine won't last very long. I don't want to criticize you but maybe with your hourly wage you should be thinking of a different route. Building an engine can get expensive and really expensive if short cuts are taken.

 

[MrSony]

the block needs the be marked as well the same as the caps. I always number them with dimples if I don't have number stamps. You can use studs but you need to have the bore in the caps lined up perfectly or the engine won't last very long

Are most GM main cap bolts the same? Like, could I get one from a Chevy or Olds 350 of the same era (late 70s, 1977 to be exact) and would it work?

 

[pontiacgp]

I don't know, look up the part numbers. If you are going to be doing this engine build then I suggest you pick up a book on building a Buick 350 so you can have the directions to build the engine and all the specs you'll need to measure tolerances. If you can find the 1977 Buick workshop manual they are very good to guide you. The first engine I built was a 76 Buick 350 and followed the Buick workshop manual I bought from a Buick dealer

 

[MrSony]

I don't know, look up the part numbers. If you are going to be doing this engine build then I suggest you pick up a book on building a Buick 350 so you can have the directions to build the engine and all the specs you'll need to measure tolerances. If you can find the 1977 Buick workshop manual they are very good to guide you. The first engine I built was a 76 Buick 350 and followed the Buick workshop manual I bought from a Buick dealer

According to a pdf of a Buick 350 and 455 service manual, the two maincaps that aren't the front, rear and thrust bearings are identical and therefore, I think it wouldn't matter if the places got switches as long as there are new bearings going in. rod and mains and cam bearings for me.

 

[pontiacgp]

According to a pdf of a Buick 350 and 455 service manual, the two maincaps that aren't the front, rear and thrust bearings are identical and therefore, I think it wouldn't matter if the places got switches as long as there are new bearings going in. rod and mains and cam bearings for me.

good luck with that

 

[lilbowtie]

Once the mains are line bored an honed they CANNOT be moved from that position. If you took the engine apart and didn't mark them - shame on you. You will find if you try to put it together the way your talking you won't get proper clearances and I'd be surprised if the crank turned. Seeing you have the mains for that block you could try finding there proper position through witness marks and measuring. Pay attention to the split line. The missing bolt is the least of your worries