Replacing Reeds on a Mercury 2.5L

[Capnmoench]

What are the advantages if I go take this front end decked .050” instead of just deck it myself .010” on glass to get rid of the deformities?

[Capnmoench]

Damn, Fishin’. You’re a helicopter mech? I’m a jet mech. I don’t think we can be friends anymore. I joke! I hear what you’re saying though. Vehicles that can pull over to the side of the road or beach aren't under as much scrutiny and testing as those that can fall into people’s houses, cities and populations. That was the only reason I thought the fiber reed might need more regular maintenance like old OMC ones (as someone quoted in another forum I was reading). I see a lot of edge delamination on carbon fiber or fiberglass in stress or impact. The impact and bending on these must be far below what I see that causes damage to the edge of some standard composite structure. . Everyone swears by them, they’re cheaper than stock, and they won’t kill the motor in failure. I’m all in.

[ChrisCarsonMarine]

What are the advantages if I go take this front end decked .050” instead of just deck it myself .010” on glass to get rid of the deformities?

I wouldn’t worry about decking the intake to fix the deformities, I can’t really tell by the picture how severe they are but I would expect a smear of sealer behind the gasket would take care of the problem, as the gasket is pretty spongy anyway. As to milling 50,000 from the intake rather than 10,000‘s, realize that this would not result in milling the 50,000 off that you read about ,when we mill for performance 50,000 it’s off the crank case front not the intake manifold, and the reason is to move the Reeds closer to the crankshaft to reduce the crank case volume. We just came up with some crankcase stuffers that bolt in between the Reeds and the gasket to accomplish this without any milling, but mailing the intake manifold Is shortening the intake tract, I don’t see any advantage to that, Chris

[Fishinmymission]

Damn, Fishin’. You’re a helicopter mech? I’m a jet mech. I don’t think we can be friends anymore. I joke! I hear what you’re saying though. Vehicles that can pull over to the side of the road or beach aren't under as much scrutiny and testing as those that can fall into people’s houses, cities and populations. That was the only reason I thought the fiber reed might need more regular maintenance like old OMC ones (as someone quoted in another forum I was reading). I see a lot of edge delamination on carbon fiber or fiberglass in stress or impact. The impact and bending on these must be far below what I see that causes damage to the edge of some standard composite structure. . Everyone swears by them, they’re cheaper than stock, and they won’t kill the motor in failure. I’m all in.

I'm an engineer doing Materials Failure Analysis. I document and experiment on parts from the field, test, or production and investigate any issues or suspected issues. We look at the threads and characterize the damage when those mechanics don't follow the torque spec or use an unspecified lubricant haha. I haven't worked on any jet parts yet but sometimes our recently new big parent company sends some C130 parts to our lab. Ever have any cracked parts and you can take good photos of the surfaces I might be able to tell you what happened. The scanning electron miscroscope really helps but half of the time if the surfaces aren't destroyed you can do it with good photos.

[Capnmoench]

I wouldn’t worry about decking the intake to fix the deformities, I can’t really tell by the picture how severe they are but I would expect a smear of sealer behind the gasket would take care of the problem, as the gasket is pretty spongy anyway. As to milling 50,000 from the intake rather than 10,000‘s, realize that this would not result in milling the 50,000 off that you read about ,when we mill for performance 50,000 it’s off the crank case front not the intake manifold, and the reason is to move the Reeds closer to the crankshaft to reduce the crank case volume. We just came up with some crankcase stuffers that bolt in between the Reeds and the gasket to accomplish this without any milling, but mailing the intake manifold Is shortening the intake tract, I don’t see any advantage to that, Chris

Oh, duh. I feel like a dumbass now. Yeah, I wasn’t thinking that I wouldn’t be changing anything to uniformly bring the whole surface down. Everything would be right where it was. Facepalm.

[Capnmoench]

Yay! The reeds are here and the intake is all cleaned up. Too bad the rain is reediculous right now. Guess I can assemble the whole thing with the carbs and have it all reedy to install when it lets up.

[Capnmoench]

Reeds are in. Maybe it idles better. Hard to tell. Plugs looked a little coked on the tips from the rich running I was seeing in my other thread. Trying an ultrasonic cleaning on them and firing her up again. Peace of mind that the reeds can be digested is well worth the $110 though. I thought for sure the gapped reeds might have been the culprit to that vibration coming off idle in the low-midrange band.

[Capnmoench]

Cleaned the plugs up. She’s definitely idling better. Might have to bring the primary down a hair on the water. It’s definitely noticeable now.

[gmacrae]

Is it still running a bit rough? Have you written all the TDC's on the flywheel and checked each is firing in time, and no double-fires etc?

[Capnmoench]

Is it still running a bit rough? Have you written all the TDC's on the flywheel and checked each is firing in time, and no double-fires etc?

It’s idling pretty good. I don’t think it’s rough. I have not gone to the trouble of checking all cylinders, just # 1. On acceleration it’s missing a bit. I have this video on my other thread. Maybe you can weigh in on if it’s sounding normal and healthy. https://m.youtube.com/watch?v=i7aqOfINFEU

[gmacrae]

It’s idling pretty good. I don’t think it’s rough. I have not gone to the trouble of checking all cylinders, just # 1. On acceleration it’s missing a bit. I have this video on my other thread. Maybe you can weigh in on if it’s sounding normal and healthy. https://m.youtube.com/watch?v=i7aqOfINFEU

Not sure I'm really qualified to comment on that video. Seems fairly smooth to me but index those TDC's anyway, it's so easy and helpful (don't have to get it perfect using a dial gauge, I just used a small screwdriver and got each one within a couple degrees. Mine runs OK when it's double firing, but definitely ran smoother than that video for the brief time I had it firing perfectly (till another switchbox s**t itself). Having those other cylinder numbers just written in sharpie on the flywheel has definitely helped.

[Fishinmymission]

Sounds pretty smooth to me. I had the same year and hP carbed engine and it would always stutter(drop RPMS) much more drastically than that especially in its last 2 years. I went crazy chasing and replacing every electrical option and It ended up being mechanical damage (spalling) between the two main crank bearings and journals. In its last year I just raised the idle timing and RPM just to prevent it from stalling at idle. If it's not stalling at the suggested idle(0-9 degress ATDC) timing and you can keep your idle RPMS below 700 you should be golden. I would also need to make small adjustments when i went fishing when it was below freezing in the colder months.