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Yahama 1992 2stroke 200 HP sensors

M

Monoki

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"Help!

I have twin 1992 Yam

"Help!

I have twin 1992 Yamaha 200HP 2-stroke counter rotating engines on a 1992 25' Grady-White. A 30-second steady sensor goes off at roughly 4300 RPM. As a result BOTH engines are dropped to ~2000 RPM for safety. I cannot identify the problem.

Short history....

(1) I don't think it's oil. Oil filters and pumps on both the integral and reserve tanks appear to be working fine. In fact I swapped between the two engines and still have the same alarm. The visual oil sensors I believe are also working as they should.

(2) I have replaced the fuel filters with 8 microns. Still same 30-seond steady sensor goes off at ~4300 RPM.

(3) I don't think it's an overheat sensor because the sensor will pop on within 20 seconds of 4300-plus RPM.

(4) It might be water pressure, although the spout appears to be very strong and nearly identical to the portside engine. I've used to Salt Away and still have same problem with the sensor.

(5) To note, and questions that I cannot answer. The problem engine has the anticavitation plate chipped on side with a small section missing. Also, I have a small transom-fixed tranducer mounted closer to the problem engine than the other. I'm only guessing that at higher RPMs too much air is going through, but even totally trimmed in, I still have the sensor go off.

Early this season, I could run at WOT and a nice 4400-4600 cruise. The first time the sensor went off was at roughly 4600 RPM and has steadily decrease to 4300 RPM.

Question: what scenario(s) trip off that 30-second steady audible sensor? Is it a specific warning or a general warning that might be the result of one of more culprits. How do I trouble shoot this?

Semper fidelis,
Chris Monoki"
 
"Yes, I have three Yami guages

"Yes, I have three Yami guages -- two for each engine and a third to guage fuel level, etc. The two for each engine has three oil status points. What is frustrating, however, is that when the 30-second warning buzzer goes off, I haven't the foggiest idea what it means -- overheat, water pressure, fuel pressure, oil level are a complex myriad of all. Hence I don't know how to troubleshoot.

T-stats and poopet valve? Forgive me ignorance, but I'm not following you here. I'm a decent troubleshooter, but not a 4-star certified Yamaha mechanic."
 
thermo stats and poppet is a p

thermo stats and poppet is a pressure relief valve
it could be clogged passageways also
 
"Thanks for the tip:

But wh

"Thanks for the tip:

But while it might be the thermo stats, I don't think it's due to overheated. For example, let's say I started the engine and ran her for exactly one minute in idle, and then got to plane at 4500 RPM. Within 20 seconds the 30-second audible warning goes off and drops me to about 2000 RPM. In 120 seconds total is not enough time to overhead the engine.

Moreover, I can run the engines at 4000 RPM for hours and at differing trims and the warning won't be triggered. Sure by then the warning would have gone off.

Regarding the poppet valve, I haven't checked it yet, but certainly will since it relates to water pressure.

JIT, do you happen to know the list of things and or sensors that can a steady 30-second audible warning and drop the RPM to roughly 2000%. I have a Clymer manual and nowhere does it say what exactly will cause that.

Secondly, let's say it's not water pressure, what are the key main culprits that will cause that alarm to go over when on plane and at, say, 4300 RPM?

Thanks much

S/F
Chris"
 
your either sucking in air or

your either sucking in air or the poppet valve and or clogged passagways

do the heads feel hot?
might be a bad sensor

yes you can over heat a 2 stroke in 2 minues of running
 
"JIT:

No, the heads are not

"JIT:

No, the heads are not hot to the touch and a thermal stick didn't melt and mess up my outboard.

When you say clogged passage ways, do you mean water, thus resulting in pressure less than ought be a XX RPM? If so, I think I can get on that.

The poppet valve I will take a look at (BTY, where is in on the 1992 200HP, Clymer doesn't have a photo of it).

So...

Regarding OIL
-- Reserve tank, filter and pump ok
-- Intergral tank pump, filter ok.

Regarding FUEL
-- Replaced 8micron cannister filter
-- Inline integral filter I haven't done anything with.

Regarding WATER COOLING
-- Did a flush with Salt Away.
-- Not sure if dirtied or if pressure good.
-- Not sure if taking in air.

S/F
Chris"
 
"bad sensor somewhere
you nee

"bad sensor somewhere
you need to get a factory manual and trouble shoot

if heads are not hot when alarm going oil, then could be temp sender

if it was oil it would do the same thing

i have the trouble shoot guide for the oil sensors
email me"
 
"Just-In-Time:

From an em

"Just-In-Time:

From an email I sent.

First, thank you so much for trying to help me troubleshoot this problem. I really appreciate it.

Secondly, I've resorted to the internet to seek help because I and the previous owner will be on the fourth mechanic and/or Yamaha services to troubleshoot this situation. They have ALL failed.

The problem at hand isn't such a big deal, in my view. Having twin 2-stroke 200HP 1992 Yahamas, I've done this:

(1) Swapped engine started from one to another. Both work fine.

(2) Swapped intergral oil tank, including level sensor from one to another. Both work fine.

(3) Swapped batteries. Both work ok, although will need to be replaced with dual purpose batteries next season.

(4) Swapped the brainbox between the two engines. They work fine.

Off season last year, I brought the Grady to TriStateMarine in Deale, MD. They came back and said that the impeller was the problem, but also billed me for a rebuilt carb. Ok.

When I got the boat in the water this season, it worked fine...for a month. After that, I can't get to WOT let alone to 4600 RPM. It has since then notched down to 4200 RPM that the warning buzzer will go off.

So I thought what had changed since then that I get the warning buzzer. Two possibles in my view. First, I ran aground and clogged the water intake. When that happened, I flush it out, taking the tell-tale out. Without precisely guage the water pressure, it seems equally as strong as the engine that doesn't have a problem. I can be wrong here.

Second, I have a a transom mounted transucer by Lowrance that is slightly more in front of the problem engine than in front of the port side engine. I think that the turbulence drummed up by the transducer would be stirring air below the CHIPPED cavitation plate. HOWEVER, the engine had the problem the season before BEFORE I put the transducer on.

Third I'm positive it's the starboard engine because I've ran the portside at 5300 RPM and no buzzer. I've ran the portside at 4700 RPM and the starboard at 4100 and not problem. I've hand both run at 4400 RPM and the buzzer goes off. Last, I've hand the portside engine off and the starboard engine run at 4500 RPM and the buzzer goes off.

Troubleshooting this thing has been next to impossible because I simply cannot get an answer to this question:

When you hear the 30-second steady audible warning resulting the engine(s) to drop to 2000 RPM, exacly what sensor(s) are doing that? Is it one? Is it five? Is it 50 sensors? I haven't a clue and the Clymer manual doesn't get into it. In fact, it doesn't even give a schematic on where all the sensors are.

But all know is this. (1) If the engine ran hot, the thermo stick would have melted. It didn't. (2) That if it was an oil flow/mix problem, then the integral and reserve tank would have different levels over time. They have the exact same level over time. (3) That if it was the brainbox, starter, integral oil tank, then the portside buzzer should have gone off when I swapped them to the portside.

So while I appreciate your help, when you say I have a 'bad sensor', it's difficult for me to trouble shoot because (1) I don't know how many sensors there are, and (2) don't know where they are located.

Any ideas would be greatly appreciated.

Semper fidelis,
Chris Monoki"
 
"you only have oil and temp se

"you only have oil and temp sensors

to me if you ran into mud i bet the poppet valve is clogged

i would buy a factory manual and start to troubles shoot, before throwing parts in

if the temp stick did not melt, then has to be a bad temp sensor"
 
"Just In Time:

Thank you.

"Just In Time:

Thank you. So, what I will be doing is a total flush of the intake system. Plus, I'm going to use Yamilube 2-M rather than just any TCW-3 oil.

As for the poppet valve: where exactly is it on the 92 2-stroke 200HP outboard? I was under the impression that poppet valve where with 4-stroke HPDI outboard.

Semper fidelis,
Chris Monoki"
 
"Just-in-time:

Funny, I fou

"Just-in-time:

Funny, I found those pics just the day before you posted them! Thanks!

Ok, I took a look at the starboard side poppet valve. It's clean as a whistle.

Obvervations:

-- The problem is the starboard. Have new small inline filter and new 8 micron filter canister as well. When running the engine, facing toward the stern, the three right side pistons were hotter than the three on the left. At 1000 RPM for 5 minutes, I can place my hand on the left side all day long. I can place my on the right side for a limited time before my hand gets too hot.

However...

The good engine, portside, all six cylnders ran at the same temp as the three 'hot' ones on the starboard engine.

Any thoughts?

Last, at 1000 RPM, the tell-tale stream on the starboard (problem engine) is STRONGER than the portside.

Thought?

Much appreciated.

Chris Monoki"
 
"JUST-IN-TIMES:

Thanks. Tw

"JUST-IN-TIMES:

Thanks. Two questions and then I'll report back to you.

(1) Since the change in gas to 10% ethanal, it was strongly suggested by TriStateMarine, a Grady-White Yamaha dealer, to switch to 8 microns.

(2) How do you clean the heads from salt water? I know how to flush the intakes, but that's about it.

Chris Monoki"
 
"Here's what I've done

"Here's what I've done:

(1) Cleaned out both poppet valves...were mostly clean anyway.

(2) Flush intake with Salt Away.

(3) New spark plugs...older ones, which are still good to become emergency spares.

(4) Four NEW thermostats for each engine...kept two as spares. Also cleaned t-stat housing with a toothbrush (like poppet valve) and flushed with Salt Away.

(5) As said before new 8 micron cannisters and cleaned the inline fuel filters on engine housing.

RESULT: the engine still drops off at 4200 RPM.

In my view, it's not overheating, and it appears that the intake is at the right pressure and is now getting plenty of flow. I'm pretty confident that it's no over heating because I would go WOT for 15 seconds, drop to 4000 RPM for 30 seconds, WAY for 15 seconds, back down to 4000 RPM. I did this for a good five minutes and the engine didn't drop off and no warning sound.

It is only at 4200-plus for an amount of time that 30-second audible alarms goes of on the starboard engine.

So, I'm thinking it's oil flow. As you said the sensors are only based on oil and heat.

With that, I know that the reserve has at least one oil level sensor. I know that the integral oil tank has an oil level sensor. QUESTION: ARE THERE OTHER OIL SENSORS, AND IF SO WHERE?

Much appreciated,
Chris Monoki"
 
"Chris,It may be a wast of tim

"Chris,It may be a wast of time ? but it may pay off doing a compression test.You may have excessive blow-by which may generating more heat on one side."
 
"Rich, Jason:

Thanks for th

"Rich, Jason:

Thanks for the input. All the posts have helped me understand the Yami much more, to say the least. And that of course is helpful.

If I need to do a compression test then I'll have to bring to a certified Yami mech because I don't have the tools nor the expertise for something like. My capacity is simply troubleshooting and preventive maintenence -- sparks, filters, flushing, poppet valve (thanks Rich, that went a long way).

Yesterday, after clearing out the poppet valve and flushing out the t-stats housings, BOTH sides of the v block seem to be running at the same temperature, and identical to the good portside engine as well.

So this still has me thinking that I still might need some flushing to do, and that there's a blockage somewhere that didn't kick out. However, with the telltale streaming as strong as the portside engine, and with new t-stats, I'm having a hard time thinking that this is a overheating problem.

Take yesterday, I went WOT for 15 secs, then less than 4100 (4200-4300 RPM seems to be the triggers point hat the engines drops off). I repeated the process running the engines at 5300 RMP (WOT) and the alarm was never triggered. Surely the heat generated from WOT and to 4100 RPM repeated would have triggered the overheating.

More, if it was solely overheating, that should happen at almost any RPM when the engine experience stress. For example, I had the portside shut down and ran the starboard side (bad side). The stress on the engine should have caused the overheat alarm trigger at, say, 3700. It didn't.

Only at 4200-4300 RPM for, say, 30 seconds, does the steady 30-second audible alarm go off.

I have yet to get this answer: when you hear a steady 30-second audible alarms that drops the engines down to a safer idle, EXACTLY what does it mean? Is it soley an overheat. Can it be a several sensors? Can the same alarm be something other than overheating?

Thanks
Chris"
 
"Rich:

Yes, there is an ala

"Rich:

Yes, there is an alarm. The alarm goes off at 4200-4300 RPM for a sustained period of time, say, 1 mintue. The alarm is the steady 30-second audible alarm and as such drops both engines down to roughly 2000 RPM until the alarms go off. THen I can resume.

If I were to go WOT, then 4100, just below the trigger -- go WOT, then 4100; go WOT, then 4100 -- repeatedly, then the alarm does not go off. Again, anything above 4200 -- 4300, 4600, 5000, 5200, WOT -- then the alarm will go off.

With a total flush, toothbrushed-cleaned poppet valve and t-stat housing, new sparks, new t-stats, I still get the exact same damn effect -- anything above 4200-4300 RPM for a sustained periond, say 1 minute, whether trimmed or out, both engines get the steady 30-second audible alarm and both engines go down to 2000 RPM for a sustained period.

I hope that is better explained what I'm trying to describe.

I still have this question unresolved: WHEN YOU HEAR THAT STEADY 30-SECOND AUDIBLE ALARM THAT DROPS THE ENEGINES TO ROUGHLY 2000 RPM, EXACTLY -- EXACTLY -- WHAT IS THE CAUSE? Is it solely based on heat and the t-stat sensors? Or is based on other sensors, such as oil flow, etc? And if it is based on other sensors, EXACTLY what are those sensors and what are they related to?

Clymer doesn't explanin that one very question I pose. The manuals are backorder and will probably arrive aftet the season is over. And seemingly, along with this board, among two others and every discussing this directly with a certified Yami mech, I have yet to get a simple, straight-forward answer.

Semper fidelis,
Chris Monoki"
 
"Hello I have a 92 200 yamaha

"Hello I have a 92 200 yamaha 2 stroke as well with the identical problem that you have. My boat is a 23 privateer with the one motor. The first day i bought it the alarm went off. i thought it was something simple.Now 4 years later and 2 mechanics down i still hav not found the problem.i have changed the 2 thermostat sensors 2 times,water pump 2 times,battery cables,and thermostats.i also disconnected the oil tank and sensor and now mix my oil in my fuel tank. still same problem."
 
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