Jet Ski Exhaust Manifold Repair

[Don52]

The exhaust manifold on my customers 1996 personal water craft (Jet Ski) was a sand casting that had two concentric tubes; an inner tube and an outer tube. The exhaust goes through the center tube and lake water goes between the two tubes. There were two holes on each side of the manifold that which I assume were used to remove the core sand from between the two tubes of the casting during manufacturing. The four holes were blocked off with caps that were welded on during manufacturing. Over time the water corroded the caps so that there were eventually two pin holes in one of the caps. My customer carefully cut off all four corroded caps and made new ones. I enlarged the holes to remove the oxidized material on the ID of the hole, because I was concerned that the contaminated material would get sucked up into the weld and contaminate it. Then I welded the four caps in place. I am guessing the a new manifold would have been pricy.

Don

[ryanjones2150]

Looks like a good repair, Don.<br />
<br />
Is that a foredom flex shaft you're using there to burr that material out?

[Don52]

Looks like a good repair, Don
Is that a foredom flex shaft you're using there to burr that material out?

Yes it is a Foredom flex shaft grinder.
I am surprised that you could identify it when looking as such a small part of it.
I really like them for fine work.
I have a ton of carbide burrs and other accessories for it.

Don

[ryanjones2150]

I have a couple myself. Great tools, handy too.

[Don52]

I have a couple myself. Great tools, handy too.

My customer sent me a picture of the original manifold with some pin punches poking through the holes in the caps of the Exhaust Manifold, before he ground the caps off. Two of the holes went all the way though one cap.

Don

[ryanjones2150]

maybe you should've welded it better, Don.

[aametalmaster]

maybe you should've welded it better, Don.

I think that was before it was fixed...Bob

[ryanjones2150]

I figured that Bob, cmon...my sarcasm escaped you?