525 CMI Header Issues?
11-09-2009, 06:52 PM
#11
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11-09-2009, 11:48 PM
#12
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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.
11-16-2009, 06:27 PM
#13
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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
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.
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Last edited by BillR; 11-16-2009 at 06:32 PM.
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Steve
11-16-2009, 10:13 PM
#15
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
Doug
Last edited by outriggers; 11-17-2009 at 07:35 AM.
11-17-2009, 07:27 AM
#17
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
Last edited by outriggers; 11-17-2009 at 07:33 AM.
11-17-2009, 08:09 AM
#18
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
11-17-2009, 10:13 AM
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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
