2004 200L Merc Optimax done at 822hrs

[kawakawa]

BBC'rs-

I have a 2004 196 Champion with 200L Merc Optimax (822hrs). It's been a trouble free combination since brand new. Always fresh fuel, factory maintenance on motor, Optimax oil, and Im not a high speed run and gun tournament guy. Most of my runs on local lakes are relatively short and at 4000rpm cruise, although I do run WOT now and again. Never had a single knock, squeak, smoke or stutter ever.

Yesterday, I launched and warmed up at idle for about 30 minutes. Jumped on plane and was trimming the motor when I lost power suddenly and motor made many strange noises. Pulled it back to idle and turned it off. Im guessing blown power head, broken reed valve, injection pump failure or ???

My questions for you veterans-

Do I compression check first then try to diagnose the problem?

If compression is off or variable, do I start looking for power heads and a certified Merc mechanic to rebuild?

Do I repower with a new 200 Pro XS?

I love the boat and it's in pristine condition with Ultrex, big screen electronics, new batts, tires, boat cover, etc., etc. Selling isn't an option, but Im retired and finding an extra $10-25K to spend on rebuild or repower will be painful! I'm in Helena, MT a long distance from many factory Merc mechanics, and I'm in a tight spot!

All suggestions greatly appreciated!

[Champ 2001]

Post this on the Mercury 3.L forum. You will get some good advice from the experts there.

[apdriver]

A compression test is a good idea to give you an idea on the health of your engine. Probably a good place to start with all the strange noises. Decowl her and give it a good visual too just to rule out a hole in block. Follow this for a proper compression test.

https://www.bbcboards.net/showthread.php?t=267446

[Highcentered]

Powerhead probably gave up. Just pulling the plugs might be enough to tell you what happened. And speed holes in the block too. Good luck! When you lost power did it lock up tight or just start sounding like metal clanking inside?

[OLD BOB]

When the compressor goes bad it sounds like a blown engine too. Not a cheap repair but better than a power head.

[bass.man65]

Best to pull plugs 1st if all are good and nothing obvious visually then I would check lower unit to eliminate that. Blown lower can sound like a bad powerhead.

[kawakawa]

Thanks, will do!

[kawakawa]

Lost power fairly gradually with knocking and noise but no catastrophic clanking or banging. Will take the cowl off and have a look this morning. Thanks for all the good advice!

[Highcentered]

When the compressor goes bad it sounds like a blown engine too. Not a cheap repair but better than a power head.

Sounded like a belt squeaking when it went out on us one night. That was a LOOOOONG night!

[printman71]

Post this on the Mercury 3.L forum. You will get some good advice from the experts there.

Be sure to read the specifics before posting, you will need serial number and other data, or you will get your hand slapped.

[TeamBoatDock]

Probably Compressor. Been there.

[Rangerdeepv]

Air compressor?

[FrancoCialone]

Worst case, rebuilding will be less expensive than replacing with a new motor. I can live with a used boat, but not a used motor, unless it has a written garantee.

[davidsa]

Hope repair is reasonable! +20 years and approaching 1000 hours. That is a great run imo.

[OH_Ranger]

Probably Compressor. Been there.

That motor won't run with a bad compressor

[Bill Reynolds]

That motor won't run with a bad compressor

Yeah, I lost a compressor on a 115 Optimax and it would start then run for a few seconds then die.

[mactlman]

That motor won't run with a bad compressor

uses the air pressure to inject and vaporize the fuel -- no air, no fuel

[BroWhoop]

My sons did the same thing. I hope yours isn't what his was. I forget the cylinder number sequence. Top cylinder on the port side I think. Good luck.