Should I or Not

[modeltee]

I posted a question a couple of months ago concerning low compression on one cylinder on my Mercury 225 EFI. Thanks for the replies. I am taking the boat this Monday to be repaired. I have saved up some additional money to do some extras on the engine. A couple of things mentioned by the mechanic were shaving and c.c.'ing the heads, porting on the intake and exhaust side and a few other mods I can't recall. Do you guys think this is a waste of money and will it create reliability issues by doing this? Thanks for your advice.

 

[Laddies]

Re: Should I or Not

Before makeing mods. make sure of the mechanics abilities or you can wind up with junk. there are a lot of talkers out there and few that can do the work. Goto the merc section at biggerhammer.com or the scream and fly forum for good info.

 

[modeltee]

Re: Should I or Not

Thanks for the guidance Admiral. Scream and Fly has all the information I need and more. Very cool site. Thanks again.

 

[CharlieB]

Re: Should I or Not

How fast can you afford to go?

What are you wanting or expecting to get out of your boat/motor combination?

proper setup will make a great improvement dollor for dollor than modding your engine.

Most reliable mechanics know this and should be willing to work with you and your boat to help get the set up right long before tearing into an engine.

Why is your compression low, a sticky ring/land may be cleaned carefully without requiring a rebuild, however and cyl wall/piston damage and you will need that tear down to correct those problems.

Any time we improve an engines breathing AND corresponding improvements in fuel flow, we can add power. How you use that added power will determine how long the engine will last.

A simple port cleaning can make a small but noticable improvement in performance without any detrimental effect on engine life.

Serious port work and fuel flow improvement and judicious compression increases will make SERIOUS power available BUT......... driving it like a like you stole it will definately shorten its life, however, careful judicious use of the throttle it can still servive for quite some time before needing refreshening.

It all depends, what you want, what you can afford, and how hard you run it afterwards.

In either case I would be very weary of who I let cut on your heads and ports. Compression increases also can require better fuel than the average found dockside.

 

[modeltee]

Re: Should I or Not

Thanks for the advice Charlie. I guess no matter what I have there always seeems to be something extra I want out of it. The boat is set up perfect and is more than adequate for my needs. I probably should leave well enough alone and it looks like I will have to. At this point all the extra cash I saved will be used for repairs I had not anticipated. I thought the only problem I had was going to be the lower left cylinder. The mechanic called me this afternoon and said all three pistons on the left side were damaged with the lower one having the wosrt damage. He has not pulled the head off the right side yet. I kind of expect the same scenario. This is really frustrating. I'm not an outboard motor technician but I would guess the oil injection crapped out. This is the first boat I have had that was oil injected. I had one boat for almost twenty years and never had a problem with it but I always mixed the oil with the gas. At this point I just hope I can get it back to good running condition witout having to buy a new engine. This has really bummed me out. Thanks for your help and advice guys.