Cmi Headers/525 Efi Problems?
01-08-2010, 06:53 AM
#71
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Water type does not seem to be the issue in the leaks and problems we have been exposed to and seen first hand.
The only headers we are now recommending are the Dana and Kieth Eikert cast type header manifolds that have been hard anodized for salt water use if so used and carefully mated to captains call-silent choice if so equipped.
We do not have enough personal expierence with other header manufacturers such as Stellings, Hardin, and Lightning to make a factual statement about how they are performing from a leak or cracking standpoint.
We are also careful to inform customers that routing exhaust outlets down and around thru right angle S-pipes and such may be a problem on bigger horsepower engines were larger cam durations and greater exhaust flow with water in the system ahead of the S-pipe or large direction changes can sometimes back water up into the header and ultimatly into the engine.
We do all our break in and dyno testing with the engines fully accessorized with raw water pumps, wet exhaust just as they will be in a boat and we have actually have expierenced water intrusion back into the engines exhaust side on the dyno with S-tubes installed right behind the riser outlets and some problems with switchable exhaust diverters like captains call- silent choice type even at idle rpms due to what we call exhaust water bounce back syndrome. This has happened with engines with fairly mild cam durations that do not revert with the exhaust properly routed and exhaust water plumbed at a better entry point.
Bottom line, on my boat I would not run a high performance engine 500HP plus normally aspirated with headers routed thru captains call-silent choice type switchable system or thru S-tube diverters to clear and integrated transom without dumping the exhaust water behind the switchable valves and after the drop in an S-tube system where the water outlet is faced toward the actual transom outlet.
This is remember Raylars opinion and is not the last word in what exhaust is right for everybody else and we are certainly not the last word in performance marine exhaust headers!
Best Regards,
Ray @ Raylar
The only headers we are now recommending are the Dana and Kieth Eikert cast type header manifolds that have been hard anodized for salt water use if so used and carefully mated to captains call-silent choice if so equipped.
We do not have enough personal expierence with other header manufacturers such as Stellings, Hardin, and Lightning to make a factual statement about how they are performing from a leak or cracking standpoint.
We are also careful to inform customers that routing exhaust outlets down and around thru right angle S-pipes and such may be a problem on bigger horsepower engines were larger cam durations and greater exhaust flow with water in the system ahead of the S-pipe or large direction changes can sometimes back water up into the header and ultimatly into the engine.
We do all our break in and dyno testing with the engines fully accessorized with raw water pumps, wet exhaust just as they will be in a boat and we have actually have expierenced water intrusion back into the engines exhaust side on the dyno with S-tubes installed right behind the riser outlets and some problems with switchable exhaust diverters like captains call- silent choice type even at idle rpms due to what we call exhaust water bounce back syndrome. This has happened with engines with fairly mild cam durations that do not revert with the exhaust properly routed and exhaust water plumbed at a better entry point.
Bottom line, on my boat I would not run a high performance engine 500HP plus normally aspirated with headers routed thru captains call-silent choice type switchable system or thru S-tube diverters to clear and integrated transom without dumping the exhaust water behind the switchable valves and after the drop in an S-tube system where the water outlet is faced toward the actual transom outlet.
This is remember Raylars opinion and is not the last word in what exhaust is right for everybody else and we are certainly not the last word in performance marine exhaust headers!
Best Regards,
Ray @ Raylar
01-08-2010, 07:41 AM
#72
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Just going to throw a couple things out here and see what others think as well ...............
Some of the problems I've seen brought up on here are staggered set ups not having the extra supports, resulting in cracking/leaking at the flanges due to all the extra weight of all the pipe it takes in this engine set up, some say the extra braces installed at the rear of the engine cure this.
Heat problem at the flange where the pipe is welded on, resulting in a similiar type of failure. This seems to be more in the earlier style that did not have the "cool collar" design that allows for more cooling water flow closer to the flange. It has been said that this newer design, "cool collar" style, is not prone to this failure.
Not saying this is gospel here, just some of what I've picked up on thru the threads related to this.
I have the newer "cool collar" style, side by side set up, with the silent choice option on the Fountain and so far have not had a problem. At least not that I'm aware of at all. I do agree with Ray in that at times things on here do get expanded a bit beyond what might be the actual deal.
Question here for Ray ........... Is there a way to tell if you have an internal leak or water reverting back in an engine that seems to be running fine? I realize that this will often show up on tear down, but can you tell otherwise?
Some of the problems I've seen brought up on here are staggered set ups not having the extra supports, resulting in cracking/leaking at the flanges due to all the extra weight of all the pipe it takes in this engine set up, some say the extra braces installed at the rear of the engine cure this.
Heat problem at the flange where the pipe is welded on, resulting in a similiar type of failure. This seems to be more in the earlier style that did not have the "cool collar" design that allows for more cooling water flow closer to the flange. It has been said that this newer design, "cool collar" style, is not prone to this failure.
Not saying this is gospel here, just some of what I've picked up on thru the threads related to this.
I have the newer "cool collar" style, side by side set up, with the silent choice option on the Fountain and so far have not had a problem. At least not that I'm aware of at all. I do agree with Ray in that at times things on here do get expanded a bit beyond what might be the actual deal.
Question here for Ray ........... Is there a way to tell if you have an internal leak or water reverting back in an engine that seems to be running fine? I realize that this will often show up on tear down, but can you tell otherwise?
01-08-2010, 07:46 AM
#73
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i dont see any one having trouble with the other brand of tube headers, if they where having promlems i sure you would here about it on this site,,i know a guy running stelling ,,, he has no problems,,=cmi always use it say it was a merc problem,,because merc gave cmi the specs for the headers,,and if you bought from cmi direct with there in house specs,you didnt have a problem,or less of them,,,that bring us to today,,dont know where cmi is with reguards to quality control
01-08-2010, 08:25 AM
#74
Registered
Just going to throw a couple things out here and see what others think as well ...............
Some of the problems I've seen brought up on here are staggered set ups not having the extra supports, resulting in cracking/leaking at the flanges due to all the extra weight of all the pipe it takes in this engine set up, some say the extra braces installed at the rear of the engine cure this.
Heat problem at the flange where the pipe is welded on, resulting in a similiar type of failure. This seems to be more in the earlier style that did not have the "cool collar" design that allows for more cooling water flow closer to the flange. It has been said that this newer design, "cool collar" style, is not prone to this failure.
Not saying this is gospel here, just some of what I've picked up on thru the threads related to this.
I have the newer "cool collar" style, side by side set up, with the silent choice option on the Fountain and so far have not had a problem. At least not that I'm aware of at all. I do agree with Ray in that at times things on here do get expanded a bit beyond what might be the actual deal.
Question here for Ray ........... Is there a way to tell if you have an internal leak or water reverting back in an engine that seems to be running fine? I realize that this will often show up on tear down, but can you tell otherwise?
Some of the problems I've seen brought up on here are staggered set ups not having the extra supports, resulting in cracking/leaking at the flanges due to all the extra weight of all the pipe it takes in this engine set up, some say the extra braces installed at the rear of the engine cure this.
Heat problem at the flange where the pipe is welded on, resulting in a similiar type of failure. This seems to be more in the earlier style that did not have the "cool collar" design that allows for more cooling water flow closer to the flange. It has been said that this newer design, "cool collar" style, is not prone to this failure.
Not saying this is gospel here, just some of what I've picked up on thru the threads related to this.
I have the newer "cool collar" style, side by side set up, with the silent choice option on the Fountain and so far have not had a problem. At least not that I'm aware of at all. I do agree with Ray in that at times things on here do get expanded a bit beyond what might be the actual deal.
Question here for Ray ........... Is there a way to tell if you have an internal leak or water reverting back in an engine that seems to be running fine? I realize that this will often show up on tear down, but can you tell otherwise?
Most of these in salt water?
01-08-2010, 09:44 AM
#75
Registered
I have the newer "cool collar" style, side by side set up, with the silent choice option on the Fountain and so far have not had a problem. At least not that I'm aware of at all. I do agree with Ray in that at times things on here do get expanded a bit beyond what might be the actual deal.
Question here for Ray ........... Is there a way to tell if you have an internal leak or water reverting back in an engine that seems to be running fine? I realize that this will often show up on tear down, but can you tell otherwise?
Question here for Ray ........... Is there a way to tell if you have an internal leak or water reverting back in an engine that seems to be running fine? I realize that this will often show up on tear down, but can you tell otherwise?
It was actually related to 496 block, whose CMIs are different (the 2 lower tubes are connected to the 2 back cylinders), but I don't see why the considerations should be much different.
Ray gave me some suggestions in that thread (aside from the main recommendation to get rid of the silent choice, that is).
For how long have you been running with your setup?
Also in my boat, after 60 hours or so with the CMI+switchable exhaust on a stock 496 (200 hours in total, previously with the stock header+switchable exhaust), the engine seems to run just fine, but what I read was enough to make me a bit worried about it anyway...
01-08-2010, 12:28 PM
#77
Charter Member
Charter Member
[QUOTE=RaggedEdge;3019777]Just going to throw a couple things out here and see what others think as well ...............
Some of the problems I've seen brought up on here are staggered set ups not having the extra supports, resulting in cracking/leaking at the flanges due to all the extra weight of all the pipe it takes in this engine set up, some say the extra braces installed at the rear of the engine cure this.
RE,
That is the exact set-up I'm looking @ a full staggered 525's in a 38 foot boat! Please see attached pic.
I'm less excited about this configuration the more I read about this problem
Dean
Some of the problems I've seen brought up on here are staggered set ups not having the extra supports, resulting in cracking/leaking at the flanges due to all the extra weight of all the pipe it takes in this engine set up, some say the extra braces installed at the rear of the engine cure this.
RE,
That is the exact set-up I'm looking @ a full staggered 525's in a 38 foot boat! Please see attached pic.
I'm less excited about this configuration the more I read about this problem
Dean
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Last edited by Dean Ferry; 01-08-2010 at 12:32 PM.
01-08-2010, 01:44 PM
#80
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Just going to throw a couple things out here and see what others think as well ...............
Some of the problems I've seen brought up on here are staggered set ups not having the extra supports, resulting in cracking/leaking at the flanges due to all the extra weight of all the pipe it takes in this engine set up, some say the extra braces installed at the rear of the engine cure this.
Heat problem at the flange where the pipe is welded on, resulting in a similiar type of failure. This seems to be more in the earlier style that did not have the "cool collar" design that allows for more cooling water flow closer to the flange. It has been said that this newer design, "cool collar" style, is not prone to this failure.
Not saying this is gospel here, just some of what I've picked up on thru the threads related to this.
I have the newer "cool collar" style, side by side set up, with the silent choice option on the Fountain and so far have not had a problem. At least not that I'm aware of at all. I do agree with Ray in that at times things on here do get expanded a bit beyond what might be the actual deal.
Question here for Ray ........... Is there a way to tell if you have an internal leak or water reverting back in an engine that seems to be running fine? I realize that this will often show up on tear down, but can you tell otherwise?
Some of the problems I've seen brought up on here are staggered set ups not having the extra supports, resulting in cracking/leaking at the flanges due to all the extra weight of all the pipe it takes in this engine set up, some say the extra braces installed at the rear of the engine cure this.
Heat problem at the flange where the pipe is welded on, resulting in a similiar type of failure. This seems to be more in the earlier style that did not have the "cool collar" design that allows for more cooling water flow closer to the flange. It has been said that this newer design, "cool collar" style, is not prone to this failure.
Not saying this is gospel here, just some of what I've picked up on thru the threads related to this.
I have the newer "cool collar" style, side by side set up, with the silent choice option on the Fountain and so far have not had a problem. At least not that I'm aware of at all. I do agree with Ray in that at times things on here do get expanded a bit beyond what might be the actual deal.
Question here for Ray ........... Is there a way to tell if you have an internal leak or water reverting back in an engine that seems to be running fine? I realize that this will often show up on tear down, but can you tell otherwise?
