How To: 4.3L Y Pipe replacement or Repair

[Boaty Boat]

Mercruiser 4.3L w/ Alpha outdrive, seawater cooling system.
I sprang a leak on Mother's Day. I found a 1/4" crack on top of the Y-pipe, just in front of where it bolts to the outdrive. It feels like it blew-out because of some burrs pointing out from the crack.

I have been unable to find information regarding this repair in my Mercruiser manual or in any of the iboat forums. I found some Y pipes on eBay for around $225, however, I am not certain I can replace this part without pulling the engine.

Must the engine be pulled to replace this part?
Can the part be welded/patched in place?
Is this crack indicative of other problems with the cooling, or exhaust, or baffles?

Any suggestions on how to proceed are appreciated.

 

[Don S]

Re: How To: 4.3L Y Pipe replacement or Repair

Must the engine be pulled to replace this part?

Yes, it's the only way.

Can the part be welded/patched in place?

In most cases, no. The cracks are usually created by corrosion.

Is this crack indicative of other problems with the cooling, or exhaust, or baffles?

Could be.

 

[Boaty Boat]

Re: How To: 4.3L Y Pipe replacement or Repair

Don,
Thanks for the quick reply. Somehow, I knew those were going to be the answers I would receive.

 

[Boaty Boat]

Re: How To: 4.3L Y Pipe replacement or Repair

I have never over-heated, the temp always runs a little over 150-160.