Fitting a serpentine alternator on a Mercruiser SBC 350

[dollar7499]

UGH! Heads were both cracked and are getting reworked. Does that mean the bottom end needs rebuilt? This is going to end up costing just as much as a rebuilt long block from rapido... but with me doing the labor instead of a skilled rebuilder

 

[alldodge]

UGH! Heads were both cracked and are getting reworked. Does that mean the bottom end needs rebuilt? This is going to end up costing just as much as a rebuilt long block from rapido... but with me doing the labor instead of a skilled rebuilder

If they are cracked, they don't get reworked they get replaced. What kind of rework is being done?

 

[dollar7499]

The guy at the head shop explained that vortec heads are so thin and prone to cracking that you would have the same chance of cracking a repaired head as you would a new one. He said they would take my cracked heads as a core and eventually weld them up and sell me a set of repaired heads for $500. When I looked elsewhere, they all said 'remanufactured' for around that same price, so I went ahead and did it.

 

[alldodge]

Walk if not run away from these guys, they either have no idea of what there doing or what is probably happening, is they see you coming in and don't have a clue. So there giving you a line saying there cracked to get more money. No one welds a cast iron head, and I would almost bet your heads are NOT cracked.

If there is anyway to be certain you are getting back the same heads you gave them, take them to someone else. My guess is yours are in the back room and they are showing you another set, and low and behold, yours will return after they drain your wallet in great shape

I guess in all fairness, the engine you got from the junk yard may have a cracked head, but not both. Look at the block and see if there is signs of an issue between cylinders

 

[Scott Danforth]

Brand new heads are $500 a pair. Used heads rebuilt and machined for larger cam with stainless valves are about $300 a pair on race junk classifieds.

No one welds vortec heads or any other readily available head. Im in agreement with alldodge, something fishy.

 

[dollar7499]

Yeah, I understand what you are saying about heads that are so readily available not being repaired, the employee was just so matter of fact about welding them up and reselling them all day long I kind of got sucked in, and when I went to research it later, I couldn't find anyone saying if it's good or bad just that its more common these days (maybe the technology for welding got cheaper?)

This is a really high volume place, I have a hard time believing they are doing something out and out dishonest. But new ones for the same price is hard to turn down, I think I will abandon those and buy some from a place online that doesn't require cores.

When I got there I hadn't had a chance to even look at them, I had just unbolted them and drove them to the head shop. He flipped them over right there on my tailgate and said hold on- look at the crack, (small, in between cylinders) and then looked at the other one and pointed out the other crack (in the cylinder running towards valve).

So I don't think they are shady, just charging too much for repair when you can get new ones so cheaply.

 

[Bondo]

and when I went to research it later, I couldn't find anyone saying if it's good or bad just that its more common these days (maybe the technology for welding got cheaper?)

Ayuh,.... Cast iron is nearly impossible to weld successfully, 'n Nope, nothin' has changed,....

With cast iron, ya weld the crack, 'n by the time it cools, it cracks right next to the weld,....
Ain't sayin' it can't be done, as I've done it, but not on a head,....

Aluminum heads are welded, 'n repaired,....

 

[Scott Danforth]

if the heads cracked near the exhaust valve, the motor was run hot (as in without coolant)

 

[Lou C]

No Title

I ran into this when I re-did the top end of my 4.3. Both heads were cracked but it did have an overheat so that was not surprising. They showed me exactly where they were cracked. As far as welding, they said that it takes special equipment and they advised installing a pair of re-man marine heads which is what I did. Each head for my 4.3 V6 was $275.

 

[dollar7499]

Hi there, have just been amassing parts for the swap back to vortec 5.7 and waiting out the cold snaps and I am all ready to go. I built a huge hoist frame from 4x6s and CAN NOT get my drive off!

I have the 6 nuts and speedo tube disconnected and have the drive in forward.. I have pulled the spark plugs so I can turn the shaft via standing on the prop. I rotate the prop one full turn and lift the drive against the wood block on top of the drive.

It opens a bit down at the bottom of the mating surface and up by the bolts on one side of the bravo 3 but not the other. The very top right nut broke off in pieces and I think the bolt is corrosion welded into the hole in the drive!

Does anyone have experience with this issue?

 

[dollar7499]

I am ending this thread because the title is no longer relevant and I don't want to be misleading and waste peoples time that search it.

I gave up on trying to fit all the 2002 brackets onto a 1984 block and heads to use serpentine parts on old wrong engine. Bought a period correct vortec engine so everything matches original build for simplicity!

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