leak from risers - 5.7L OMC

[HighLineCBR]

1989 5.7L OMC Cobra

I notices small drops coming out from where the riser sits on the manifold. This happens on both the right and left side. I noticed that this happens only in high RPMs and after i replaced the water circulating pump. I think the new pump creates bigger flow of water through the enging and therefore the slight leak.

My question is this... Should I be immediately worried about this? Will it unexpectedly blow on me? or will the leak continuously get bigger and bigger?

Do i need to replace the manifold and riser or can i just replace the gaskets?


Thanks

 

[bruceb58]

Re: leak from risers - 5.7L OMC

You need to pull the risers at a minimum and inspect them. If they are ok, you can put new gaskets on.

You use the boat in saltwater?

 

[HighLineCBR]

Re: leak from risers - 5.7L OMC

always fresh water use

 

[HT32BSX115]

Re: leak from risers - 5.7L OMC

My question is this... Should I be immediately worried about this?

Yes. If the riser gaskets begin to leak water into the exhaust area, and it happens immediately after shutdown you will have water running directly into cylinders with open exhaust valves.

If you try to start it right after that happens it may cause a hydrolock.

If it happens and you store the boat for an extended period of time you'll have rust form on the cyls.

 

[bruceb58]

Re: leak from risers - 5.7L OMC

always fresh water use

You will more than likely be able to reuse your risers and manifolds but will need new gaskets.