Replace cracked block?

[winsorcoke]

I have a problem. I was an idiot and didn't winterize my boat properly and as you can guess, the block cracked. Other than the crack, the engine runs great. It was rebuilt not long ago. My question is, can the guts of my current engine be salvaged and placed into the same model bare(used maybe) block? My boat is a 1981 with an OMC GM small block. Not sure how to figure out exactly what engine it is. Any help you guys can give would really be appreciated.<br /><br />Thanks,<br /><br />Jason

 

[badass]

Re: Replace cracked block?

depending on the severity of the crack a good engine shop can repair it. as far as taking your engine parts and putting them into a bare block it could be done but labor wise $$$$ your better off buying a remaned long block and installing your intake, carb, exhaust manifolds, etc. on to it

 

[winsorcoke]

Re: Replace cracked block?

How exactly would they repare it? The crack is about three inches long and it runs horizontaly below the exhaust manifold which is cracked also. My thinking is to just find a used empty car block and build it with the marine grade parts I have. I would do the work myself mostly. I'm just looking at the cost between $1200+ for a remanufactured block and maybe $200 for a used empty block. It's a 305 Chevy small block. Junk yards around here have piles of them. Am I just barcking up the wrong tree here?

 

[Martin Leaney]

Re: Replace cracked block?

Check your oil if it has water in it (like mine has) then the block has more than one crack and is not worth trying to fix.

 

[xltier]

Re: Replace cracked block?

u probably wont find a used block with decent cylinder walls.u should at least bore the used block and use new pistons.still cheaper.

 

[Bondo]

Re: Replace cracked block?

Your engine was Recently Rebuilt.??....<br />Were the Standard Bore pistons used ??<br />You'll need a block to Match....<br />There's No Reason at all, You can't do what you Want to do...........

 

[winsorcoke]

Re: Replace cracked block?

Originally posted by Bondo:<br /> Your engine was Recently Rebuilt.??....<br />Were the Standard Bore pistons used ??<br />You'll need a block to Match....<br />There's No Reason at all, You can't do what you Want to do...........

I was told by the dealer that it was rebuilt shortly before the previous owners traded it in. I don't know if it's true or not. All I really know is it runs VERY well for it's age.<br /><br />So what I gather from all this is it is possible to do what I asked, and I would be better off boring the used block and get new piston heads to match. And the only way I wouldn't need new piston heads is if the ones I have are not standard so the new block can be bored to those. Does that sound about right?<br /><br />One last question. How can you find out what motor you have using the model number? Mines #990261K<br />It says OMC 230 on the valve covers and the boat is an '81<br /><br />Thanks for all the help! I really do appreciate it.

 

[mitchcole]

Re: Replace cracked block?

Luckily - you've got a gm motor. They are virtually all the same except for the change in the rear main seal and the head types.<br /><br />In 1981, you've probably got regular old heads with the angled intake manifold bolts. (there were different heads for the tuned port injection heads and the vortec style.<br /><br />If you've good with motors - I'd go for the Crate engine option. Use your sheetmetal, intake and exhaust system. Go for the 350 size over the 305. The intakes will match up - just cheaper and a little more low end grunt. These $1200 engines are rated at 250 hp. <br /><br />There are too many unknowns around the parts you have in the rotating assembly to bother with boring out another block - you might save a couple hundred bucks after the block, bore, hone, and new rings.

 

[sculbert]

Re: Replace cracked block?

Go for the new engine, You will be happier in th e long run.

 

[f_inscreenname]

Re: Replace cracked block?

If you are good with a wrench I would do this. I would get a complete rebuild able 350 from the junkyard $200.00. From there I would rip it down and find out weather there was any oversize pistons or bearings and then call or go to the web site for northernautoparts.com. Buy a master rebuild kit (all rings, bearing, pistons, cam, lifters, timing set, oil pump, all gaskets and freeze plugs) $200.00. Name brand quality parts. I wouldn't recommend if I didn't use myself. You will have to tell them you want brass freeze plugs your cam specs and any over sizes you need (bearings or pistons). Hold a $150.00 for machine work (if the motor was running when you bought it I don't think you will need it). Put it together and you are ready for the swap. In the mean time you can still use your boat (if you can). When ready, pull the stuff off your 305 that you will need, pull it and drop in the new motor. Chevy motors are the easiest and cheapest to work on. If you buy a long block you get what they sell you not built to your specs. Plus it will cost you twice as much. Some of the best advice I was given when building a motor was to have it balanced. Best $100.00 you will ever spend and your motor will love you for it. I have to admit I don't think I would ever buy a reman motor. A few years back I pulled a Ford 302 boat motor (with a remanufactured tag on it) for a rebuild and I couldn't believe my eyes. Three different size pistons (standard, 20 over, 30 over), three 289 connecting rods, five 302 rods and it goes on from there. I know what is in my motor and unless you pay out the butt you are never sure. Check out some web sites on remaned motors get the specs on them and I bet you can build it for half if you do a little research.

 

[winsorcoke]

Re: Replace cracked block?

That sounds like a good plan f_inscreenname.<br /><br />If it's not much trouble, could someone fill me in on what parts would be interchangable between a 305 and a 350? For instance, the water pump, intake manifold, cam....<br /><br /><br />Thanks!

 

[Bondo]

Re: Replace cracked block?

If it's not much trouble, could someone fill me in on what parts would be interchangable between a 305 and a 350? For instance, the water pump, intake manifold, cam....<br />

Everything that's Not included in/on a Long Block Crate Engine...........

 

[winsorcoke]

Re: Replace cracked block?

Originally posted by Bondo:<br />Everything that's Not included in/on a Long Block Crate Engine...........

Would that hold true for a 350 short block? I'm assuming yes.<br /><br /><br />Thanks.

 

[winsorcoke]

Re: Replace cracked block?

double post

 

[Bondo]

Re: Replace cracked block?

305 Heads have smaller Combustion Chambers,+ Smaller ports......<br /><br />They'll Bolt on,<br />But I recommend you Don't use them......<br /><br />Go with a 350cid. Long Block....

 

[f_inscreenname]

Re: Replace cracked block?

Build your 350 from intake (should use a good Edelbrock) to oil pan. Then take everything that bolts to your 305 (alt, dist, water pump, carb, exhaust mans, etc) and put them on the 350 and go. Easy swap.

 

[winsorcoke]

Re: Replace cracked block?

So all internal parts should be new and most come with the master rebuild kit. What about the intake manifold? would that fit the 350? The guy next door has a decent running (I think '76 or earlier) 350 short block in his truck that he wants to swap out with the 350 in his other truck that he is willing to sell me. Right now he has a junk alluminum intake on it and I would prefer not to use it. What do you guys think?

 

[f_inscreenname]

Re: Replace cracked block?

Intakes are cheap. If you dont want to use it dont but I would find out what it is and look it up. Intakes usually don't go bad (just look bad) that and I don't think you need a top of the line intake.

 

[Bondo]

Re: Replace cracked block?

The 1 you have Will Fit.....

 

[winsorcoke]

Re: Replace cracked block?

That's what I wanted to hear.<br /><br /><br />Thanks guys. You've all been a very big help!