525 CMI Header Issues?

[ActiveThunder]

Originally Posted by blowntaylor

Is it ok to leave the pink antifreeze in them after winterizing? Or drain that out too.

That's part of the closed cooling system.

[REMEDY]

Pat, I mean leaving the antifreeze that I ran through the seawater side of the system to winterize it. Filling the headers and heat exchanger etc. I didn't drain the closed side as it has antifreeze in it. I would think the antifreeze would help protect the headers.

[BillR]

Originally Posted by outriggers

There is a factory mod to remove the bypass hoses and drill the top fitting on the Stb. side. More water goes though the headers. I think it keeps the headers cooler making the the heating and cooling cycles not as extreme. The letter I have says #OM956327 and up. Doug

Actually, I believe it is a fitting that screws in - not 100% sure, but whatever - remove it or drill it! The restriction might be on both sides.
Much better flow and will help to last longer.
Leave the AF in or drain. No big difference either way. As long as the AF has traveled through the header; then you'll be fine. The AF displaced any water and left a film to help protect against corrosion.

[509 SC]

Originally Posted by ActiveThunder

That's part of the closed cooling system.

Honestly these people from Florida just don't have a clue Steve

[outriggers]

Here is the info I recieved. Both bypass hoses are removed and pluged. Stb. side is drilled out to .406 or 13/32 drill bit. Port side was already .406 like the drawing shows. Check your model. Doug

[REMEDY]

Bypass hose? Are you talking about the hose from the Water manifold that runs up to the header collector at the back of the water manifold?

[outriggers]

It runs from the back of the water manifold under the header to the bottom of the tailpipe. In the diagram they are circled on the bottom of the tailpipe. After this is done all the water goes through the header then the half moon top hose out the tail pipe. The back of the water manifold and bottom of the tailpipe are plugged after the hoses are removed. The top fitting is drilled out to 13/32 on the stb. side. The only reason I found out about this is I bought a new set of headers. I went to put it together and the fittings on the water manifold were different which prompted some phone calls. The hoses that are removed are aprox 10" long and 1" I.D. I would think this would apply to any engine with sweepers, but please check. Doug

[outriggers]

I bought the plugs at Home Depot but they didn't have a 13/32 drill bit but Lowe's did. I just put plugs in the aft bottom of the water manifold for now, I'll get the bushing for the blue wing plugs in the spring. P.S. I pulled the plugs and let the anti-freeze drain. I sleep better that way, just paranoid about any fluid sitting in the headers for any lenght of time even with new headers. The engine has dyno time only. Doug

[REMEDY]

thanks. Thats the hose I thiught. I will call CMI and make sure. I see the picture, Who do you work for?

[dennis1009]

Originally Posted by outriggers

It runs from the back of the water manifold under the header to the bottom of the tailpipe. In the diagram they are circled on the bottom of the tailpipe. After this is done all the water goes through the header then the half moon top hose out the tail pipe. The back of the water manifold and bottom of the tailpipe are plugged after the hoses are removed. The top fitting is drilled out to 13/32 on the stb. side. The only reason I found out about this is I bought a new set of headers. I went to put it together and the fittings on the water manifold were different which prompted some phone calls. The hoses that are removed are aprox 10" long and 1" I.D. I would think this would apply to any engine with sweepers, but please check. Doug

Excuse my not knowing. Why drill out the top fitting to 13/32?