150 TXRC oil in air intake & rough at low rpm

[Psalm 99]

Good morning: My engine has been running real well since you guys last helped. Out on water yesterday and, after about 2 hours @ 2300 rpm, engine began to sound a little rough with a corresponding slight increase in vibration. I've been *****ing at this speed for most of the season so, took in rods and went about 10 miles @ 3000 rpm. Engine sounded good, back to *****ing, problem re-appeared. Sometimes engine slow to respond to throttle. Back up to 3000 rpm for 10 minutes and harbor. Engine a little rough again at low speeds. This is a rainy, humid area (west coast of Hawaii) but I only have about 20 hrs on a new 10 micron Sierra fuel/water separator. Figure that much running should have flushed any water build-up. Ran engine on muffs and idled about 100 rpm slow. Also, when I took the air cover off the carbs, there was about 4 tablespoons of clean 2-cycle oil trapped in the bottom of the cowling. Figure this might just be an accumulation over time due to tilting the engine up after running and getting a little after-flow from the oil injection system down and out thru the carbs, but I've never seen this before. Sure appreciate any advice. - Al

[TownsendsFJR1300]

Did you dump the water separator and check for water?

I would also drain the carbs(at the bowl drain screws) and catch what comes out in a clean container. Your looking for any water or crap. prime the bulb if need be to get fresh fuel thru there.

Any water in the separator (or engine) will make it run crappy and won't burn off as is.


Just as a side note, I use this product that helps keep any moisture mixed up and eventually burn off(besides being a stabilizer): Third video down, http://k-100.com/videos/demonstration-videos/

[Psalm 99]

Thanks for the input. This has been a reoccurring problem so I did do the items you suggested. Usually, engine gains about 100 rpm and gets back to normal on idle. This time, engine dropped 100 - 150 rpm and was close to stall. Ran for about 10 minutes. K-100 seems like a good bet. Amazon even has free shipping. Thanks again.

[TownsendsFJR1300]

Did you find any water in the filter or VST?

You may consider the water separator with the drain on the bottom if there's that much water(get it drained as you operate and keep it out of the engine altogther):

[Psalm 99]

Not a lot of room (height limitation) where the existing fuel/water separator is located. Your unit really seems nice and it would not be difficult to simply re-plumb for an exposed unit inside the transom. Still not sure what the problem is but it manifests itself identical to a water-in-fuel problem which I've had in the past. Problem is that the pretty simply solutions aren't working right now. I'll empty the new Sierra filter today and check for water.

[TownsendsFJR1300]

My fuel water separator originally didn't have the cup on the bottom (just a spin on) as there wasn't enough room (as you mentioned)

I took some 1/4" flat aluminum, duplicated the mounting holes onto that (times two), then raised that entire assembly several inches (just enough to spin off and clear the deck).

You can see the top, two bolts ABOVE the top of the transom..

No new holes in the transom, I tapped and threaded the flat bracket to filter assembly for a nice, clean fit.

Something to consider if room is an issue..

[Psalm 99]

That's a clean job Scott and I've got all the parts you mentioned. Can you recommend a good filter? Yours looks like good quality.

[TownsendsFJR1300]

That's a clean job Scott and I've got all the parts you mentioned. Can you recommend a good filter? Yours looks like good quality.

The actual base (aluminum) I've had for at least 15 years and refinished it with Rustoleum after the original paint peeled. The mounting brackets on most are very similar except for the filter seal(some are slightly larger or smaller)

I forgot what brand it is off hand, Sierra is a very good product (and not terribly expensive). Their making SS units now, a bit pricey but you won't be re-painting or dealing with aluminum corrosion.

If your placed that filter with cup under deck, to my knowledge it CAN'T be PLASTIC. Above deck, plastic is fine.

10 microns is the standard filtering size although fuel injectors can get clogged with much smaller particles. It was posted here of a 2 micron filter, which is great, except its more likely to clog.

You should be fine with the 10 micron filter.

I like the idea, I can see any water easily and drain it with a thumb screw right there...

Now, with the K100, I don't get ANY VISIBLE WATER IN THERE (as it keeps the water in suspension and eventually burns off with use)...

[boscoe99]

If your placed that filter with cup under deck, to my knowledge it CAN'T be PLASTIC. Above deck, plastic is fine.

A common misunderstanding that can't be corrected. Misinformation gets passed on the inner web around, and around and around. And around.

A plastic bowl, as long as it is used on an outboard powered boat, is OK above or below deck.

The law does not specifically prohibit the use of plastic bowls below deck. The law mandates a fire test. But that law is not applicable to boats powered with outboard motors. The plastics used in the bowls that are available to us today don't pass the test. Now if a type of plastic was used that could meet the fire test, a plastic bowl could be used on any type of gasoline powered boat below deck.

Don't blame me about the law not being applicable to outboard powered boats. I don't write the laws. Sometimes I don't even obey them

[TownsendsFJR1300]

I did write the caveat "to my knowledge" as it has been discussed here before..

[pstephens46]

You ever use that boat? No black stains running down transom from bracket grease? How is that possible?

[scofflaw]

You ever use that boat? No black stains running down transom from bracket grease? How is that possible?

My thoughts exactly, along with the motor pics.

[TownsendsFJR1300]

My thoughts exactly, along with the motor pics.

Its a 1997 hull (demo) I bought new in '97.

I take car of my stuff(wash, wax, flush, cover, RF, etc).

Genuine Yamaha grease used on all grease fittings, a little excess left there but huge globs are removed, there's no globs to stain the hull /. transom

Here's the boat prior to 2006 with the original Evinrude, then later (2007) with the Yammy. Here's my 2007 Yamaha MC with currently 22,000 miles. Bought it wrecked (4,500 miles) and repaired it..

[pstephens46]

I thought about taking a pic of one these filthy crab boats around here and claiming as my own. My actual boat falls somewhere in between that and yours as far as shine...

Townsend, betting you replaced windshield? Where did you get it? Had a source called UPD but they got terrrible reviews on Google. Backed away from sending mine at the last minute. Please don't tell me you made it.....

[TownsendsFJR1300]

I thought about taking a pic of one these filthy crab boats around here and claiming as my own. My actual boat falls somewhere in between that and yours as far as shine...

Townsend, betting you replaced windshield? Where did you get it? Had a source called UPD but they got terrrible reviews on Google. Backed away from sending mine at the last minute. Please don't tell me you made it.....

That's the original windshield... Its got a little glaze to it but not bad. The boat's ALWAYS been under cover. Before the post lift, I had a custom cover made(still have it in the attic)

Can't see much of the windshield here but I would think you could buy a new one for an "Angler 204 CC" boat.