525EFI Valve Springs Concerns
#22
I'm at work now and don't have the part numbers here. Maybe Brian Orlandi will see this and answer or I will find out later. Normally I would do this myself but Brian did a leak-down test and a visual of the combustion chambers with a scope and there was no sign of reversion. He will check installed height. Also, I have silent choice and it is fine if you only use it at idle. I pulled the headers and will pressure test them before re-installing.
[ATTACH=CONFIG]533769[/ATTACH][ATTACH=CONFIG]533770[/ATTACH][ATTACH=CONFIG]533771[/ATTACH][ATTACH=CONFIG]533772[/ATTACH]
Last edited by HyFive578; 12-06-2014 at 05:31 PM.
#23
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#24
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Silent Choice and 525's are NOT a good combination especially if the motor is close to the transom. This is what 525's do when you have Silent Choice. And before anyone chimes in and says this is from leaking headers, it's not. I've done extensive pressure testing on the headers with not a single leak. Using the Silent Choice is NOT the problem; the problem is that the reversion can be caused by tails being short and the water dump being too close to the collector because of the Silent Choice. This is a known issue with 525's and silent choice and another one of Mercury's dirty little secrets. Don't believe me? Call Mercury and ask them about Silent Choice and 525's and see what they tell you..
[ATTACH=CONFIG]533769[/ATTACH][ATTACH=CONFIG]533770[/ATTACH][ATTACH=CONFIG]533771[/ATTACH][ATTACH=CONFIG]533772[/ATTACH]
[ATTACH=CONFIG]533769[/ATTACH][ATTACH=CONFIG]533770[/ATTACH][ATTACH=CONFIG]533771[/ATTACH][ATTACH=CONFIG]533772[/ATTACH]
The Isky part number for stock spec replacement springs is 8005A.
Last edited by thirdchildhood; 12-06-2014 at 05:44 PM.
#25
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Silent Choice and 525's are NOT a good combination especially if the motor is close to the transom. This is what 525's do when you have Silent Choice. And before anyone chimes in and says this is from leaking headers, it's not. I've done extensive pressure testing on the headers with not a single leak. Using the Silent Choice is NOT the problem; the problem is that the reversion is caused by the tails being short and the water dump being too close to the collector and the exhaust pulse sucks the water back in when idling. This is a known issue with 525's and silent choice and another one of Mercury's dirty little secrets. Don't believe me? Call Mercury and ask them about Silent Choice and 525's and see what they tell you..
#26
Do you have the proper Z shaped divertors? They dump the water further downstream then the standard Y pipe does. I haven't had any issues and the Mercury 525 service manual says that Q&Q exhaust can be used up to 2,500 RPM. I only use mine sometimes at idle. Since my headers never get hot I also left the water flow restricters in place.
The Isky part number for stock spec replacement springs is 8005A.
The Isky part number for stock spec replacement springs is 8005A.
#27
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I can tell you this for sure: Merc. and CMI didn't offer the Silent Choice. Fountain, did that one their own. This was due to customer request, if you look at the down diverter tube, you will see, it's going in the opposite direction, than the normal install from what I see in your picture.
A friend of mine worked for Merc Racing for 32 yrs and was active in the project. He stated to me, they didn't want silent choice on that package and also speaking to someone else, highly involved at Fountain, stated to me the factory added the silent choice.
A friend of mine worked for Merc Racing for 32 yrs and was active in the project. He stated to me, they didn't want silent choice on that package and also speaking to someone else, highly involved at Fountain, stated to me the factory added the silent choice.
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[ATTACH=CONFIG]533794[/ATTACH] This is a 47, I sent to Acapulco. The boat has CMI Aft Fire Mufflers, from factory. I think; Fountain, may have changed their thinking at some point.
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Silent Choice and 525's are NOT a good combination especially if the motor is close to the transom. This is what 525's do when you have Silent Choice. And before anyone chimes in and says this is from leaking headers, it's not. I've done extensive pressure testing on the headers with not a single leak. Using the Silent Choice is NOT the problem; the problem is that the reversion is caused by the tails being short and the water dump being too close to the collector and the exhaust pulse sucks the water back in when idling. This is a known issue with 525's and silent choice and another one of Mercury's dirty little secrets. Don't believe me? Call Mercury and ask them about Silent Choice and 525's and see what they tell you..
[ATTACH=CONFIG]533769[/ATTACH][ATTACH=CONFIG]533770[/ATTACH][ATTACH=CONFIG]533771[/ATTACH][ATTACH=CONFIG]533772[/ATTACH]
[ATTACH=CONFIG]533769[/ATTACH][ATTACH=CONFIG]533770[/ATTACH][ATTACH=CONFIG]533771[/ATTACH][ATTACH=CONFIG]533772[/ATTACH]
Thanks