Joe Reeves Challenge to troubleshoot my 1989 175 GT engine!

Joe, I hope I haven’t scared you away? I guess you probably have a life outside of troubleshooting my problems, even though I am so fun to work with.

While awaiting your guidance, I continue to try and learn what I can about the engine. While doing this, I found the following chart at:http://www.outboardignition.com/page40.asp

Next to my engine, 150-175 35 AMP - 1989-1991, there is a column referring to “Trigger ohms” and the wire colors seem to be the ones you had me test. My questions are:

Why do they only show the one group of wires, wht,blu,pur, and grn, when I have two groups?

Am I reading that they are calling for “open” for “ ohms”?

Is this for my engine, or am I wrong and I have a different engine?

Thanks again

crashkaloop said:

From what you've said... good spark on the starboard bank, and no spark on the port bank, if it pertained to a timer base sensor problem, you should have good readings on one plug and no readings on the other.mIts actually the other way around, good spark port, no spark starboard.

I don't have a 1989 service manual anymore but my other books go up to 1986 and they all give the same sensor readings of 17 ohms +/- 5 ohms. I don't understand the readings you're getting. My readings could be 20-25 ohms, and this would be a little closer to the specs above.

Click to expand...

Yea, I was aware that the PORT bank was the one with good spark... just a senior moment on my part.

Your timing sensor readings could vary from 12 to 22 ohms and still be good. When I said "I don't understand the readings you're getting", I was speaking of the conflict between the two plugs.

crashkaloop said:

I found the following chart at:http://www.outboardignition.com/page40.asp

Next to my engine, 150-175 35 AMP - 1989-1991, there is a column referring to “Trigger ohms” and the wire colors seem to be the ones you had me test. My questions are:Why do they only show the one group of wires, wht,blu,pur, and grn, when I have two groups? Am I reading that they are calling for “open” for “ ohms”?

Click to expand...

The single mention of wht to blu/pur/grn is simply stating the test procedure without duplicating itself.

There are two timer sensor tests mentioned for the 1989 175hp.............

One for the 10 ampere stator: 35-45 ohms
One for the 35 ampere stator: 0 ohms

Frankly I don't comprehend either of them and unfortunately I don't have the OMC factory service manual to fall back on.

Yep, I get those senior moments all the time! Sometimes, the moments turn into hours?

I am confused about the conflict between the plugs as well. I do have the 35 ampere motor, and my original test with my digital VOM showed zero, so could that have been correct? And if that tells us that the timing sensors are good, what conclusion does that bring us to?

Thanks for the help, and the expertise!

I forgot to mention, I also did the following test and got the correct readings.

No fire or Intermittent on One Bank:

1. Check the stator resistance. You should read approximately 1000 ohms from the brown wire to the brown/yellow wires and 100 ohms from the orange to orange/black.

Yep those are the ones. 950k..OK that looks good. Measure the voltage while cranking and verify >150 v and you can eliminate the stator as the problem.

I''m sorry, not 950k,.....950 ohms. Or 1k to be loose about it....

Thanks daselbee! Can you tell me how and where to measure? Don't say with a VOM in my driveway!

By the way, I only have a plain old VOM.

Yes, just disconnect the brown wires at the rubber plug, set your meter on AC volts, maybe say the 300v range (200 if you have that one), and probe inside the connector with both meter leads. Have someone crank the engine. You don't need a DVA adapter/meter for this voltage, because it is not a sharp spike, it is a continuous AC waveform. BUT since you don't have the DVA, and since you are reading AC volts, the voltage I posted above will not be what you see. I would look for >100v AC at cranking speed, and most importantly, that both sides (pairs of browns) are the same. If you want to get really smart, you can swap the brown pairs, if the wires will reach. Where they are plugged right now, just swap them. If the problem is in the stator brown pairs, the NO SPARK ONE SIDE will swap sides. These brown pairs are called the "CHARGE COILS", there are two of them, one for each bank, and they provide the high voltage to the pack that is switched thru the pack and eventually makes it out to the primary coil wires. They have nothing to do with the charging of the battery....they "CHARGE" up the CDI powerpack. While this swapping and testing is occurring, the engine may start, so be careful.

OK, Both sides read 180-190 volts (jumps around a little) Is this too high? I didn't roll the wires because I thought the problem wouldn't change as both sets of wires have the same voltage. Can I now say absolutely that the stator is good? If yes, then what's next?

No chance of the engine starting as plugs are out. :rolleyes:

Just a small sidetrack.

My horn is not giving the single chirp when the key is switched on. Now, the only alarm wire I have active is the high temp alarm. All oil related alarms have been disconnected, and I am running premix. The temp alarm works fine when I ground each lead.

Can someone tell me what sends the single beep (or maybe its a couple beeps) to the alarm horn when the key is first turned on?

The horn itself has circuitry that chirps the horn when power is applied to it. The fact that you have 180-190 v on the browns is great. The stator IS NOT causing your lack of spark to one bank. Look to the timerbase or the pack. It is NOT SAFE to swap the timerbase plugs to the pack for testing. And, just for double checking, you DO NOT have a shift interrupt switch, do you? I have not looked at the parts diag, maybe someone will chime in regarding whether or not you have one.

Timer base......two sides (plugs) to that device. One plug has a black/white stripe wire, the other side has a white wire, and both sides have blue, purple, and green wires. The blue, purple, and green wires are the signal pulse source into the pack that fires each cylinder. Blue will be the top cylinder, purple is the middle cylinder, and green is the bottom cylinder. So, if for example, you had a broken blue wire on the STBD TB connector, then #1 would have no spark. Again for example, if you had a broken purple wire on the PORT TB connector, then #4 would have no spark. Now, then, if you have a broken white, or broken black/white (the only other two wires) then you would have no spark at all on any cylinder. Timer bases are complex electrical circuits. There are diodes, SCR's, and coils in there that detect the high speed spinning of the magnets on the center ring of the flywheel. Since it has those semiconductors in there, it is almost impossible to use today's VOM meters to test resistances. The results will vary from meter to meter and from timerbase to timerbase. Trust me, I have experimented extensively. But, you say, the books tell you to read x ohms...etc. Yes, and the books say to use only those old Stevens meters for the readings. They always specify which meter they used for the readings. I for one don't have the Stevens meter, and I don't know anyone who does.....maybe Joe still has his....anyway, I hope I have not led you wrong, or confused the matter any more than it is right now.

So, my aftermarket horn will never beep. Ok, I can live with that and I will just manually check it every once in awhile, or I could install a simple switch to test it every time I use the boat.

On second thought, I installed a automotive horn on this that will blast me outa the boat. My boat's horn doesn't work, so I might as well rig this up to be both my alarm, and boat horn. That way I can just toot the horn for the test, and I know if the horn goes off on its own, that will be a high temp alarm.

GREAT! The stator is good!

Absolutely there is no shift interrupt switch!!!

Thanks daselbee! Very happy that one thing has been eliminated.

daselbee said:

Timer base......two sides (plugs) to that device. One plug has a black/white stripe wire, the other side has a white wire, and both sides have blue, purple, and green wires. The blue, purple, and green wires are the signal pulse source into the pack that fires each cylinder. Blue will be the top cylinder, purple is the middle cylinder, and green is the bottom cylinder. So, if for example, you had a broken blue wire on the STBD TB connector, then #1 would have no spark. Again for example, if you had a broken purple wire on the PORT TB connector, then #4 would have no spark. Now, then, if you have a broken white, or broken black/white (the only other two wires) then you would have no spark at all on any cylinder. Timer bases are complex electrical circuits. There are diodes, SCR's, and coils in there that detect the high speed spinning of the magnets on the center ring of the flywheel. Since it has those semiconductors in there, it is almost impossible to use today's VOM meters to test resistances. The results will vary from meter to meter and from timerbase to timerbase. Trust me, I have experimented extensively. But, you say, the books tell you to read x ohms...etc. Yes, and the books say to use only those old Stevens meters for the readings. They always specify which meter they used for the readings. I for one don't have the Stevens meter, and I don't know anyone who does.....maybe Joe still has his....anyway, I hope I have not led you wrong, or confused the matter any more than it is right now.

Click to expand...

I do not think you have led me astray at all. But I am confused about these test on the timer leads.

If you go to this link: http://www.outboardignition.com/page40.asp

You will see for my engine, the test calls for no continuity?? When I used my digital VOM, I showed open on all those wires. But as a side note, I did get a reading between the blk/wht and the wht. This shows me that neither the wht or the blk/wht are open, so maybe that indicates that they are not the cause of my one bank spark problem. But my question is if that chart is right? Should these be open?

Jeeze, I hope that will be clear enough for you to understand?

OK, Joe and daselbee, most important question for you right now.

You might not be happy with me proceeding this far, but I am trying to get the boat to a point where I can use it next week during a week’s vacation.

I am a big fan of properly troubleshooting problems, and not just throwing parts at something. But I am also a big believer in having some important or hard to find parts, that commonly fail, on hand so outings are not ruined.

So a few days ago, I ordered a new OMC Power Pack, and it has just arrived. I could just through it in and see what happens, but I will not do that unless you agree that I should. I do not want to damage the new PP, or anything else.

Can you give me your thoughts on if I should install it now? If not, can you advise the next step I should take to precede getting spark to the starboard bank?

By the way, I tested all the plugs for spark again today, as I have been the victim of intermittent problems before. Nothing has changed. There is still no spark on the starboard bank, and a good 7/16 spark on the port.

Awaiting advice.

In my opinion, you will not damage the new pack. If it were me, I would go ahead and put it on. No return on electrical parts is the usual rule anyway, so you are stuck with it. I think the problem is your pack, based on what I have read, and the postings so far.

SUCCESS!
I got great spark, and the engine started right up. Thank you so much.

Unfortunately, it didn't seem to be running all that well?

But well enough that I couldn't shut it off…hahaha!

I had to pinch off the fuel line to stop it. I have never had that happen?

Also, there is some water coming out where the lower unit meets the bottom leg of the motor. Maybe that’s normal, but I never noticed it before. I am not talking about the normal holes where water comes out, I mean right where I assume a gasket would be between the upper and the lower unit, where you change the oil.

I just changed the oil when I first got the boat about 3 weeks ago. It was a little murky, but not bad.

If you are still sticking with me, what is next?

Grateful and awaiting.

(Ignition Kill Circuit)
(J. Reeves)

A Black wire (ground) should lead from the powerhead to the powerpack. There will also be a Black/Yellow wire leading from the powerpack to a raised "M" terminal of the ignition switch. To complete the circuit, there will be a Black wire from the other "M" terminal of the ignition switch to ground.

When the key is in the OFF position = The two "M" terminals are connected,. effectively shorting/killing the ignition.

When the key in ON position = The two "M" terminals are not connected and the ignition is engaged.

The water leakage... no gasket is used there, it'll eventually seal with marine debris, salt, etc. However we normally used OMC Adhesive which is now Bombardier 3M Product #847 on the top surface of the lower unit to create a seal rather than have a customer complain about the leakage.

Yep Joe, The wire and it's boot had come off. It works now.

I will take the boat out tomorrow and spin her up a bit. It seems to be loading up a little at idle, so I think it may clear up when I get it up to speed a little.

I checked the temp on both heads as it was running on the water muffs with an IR gun, and they are at about 130-140. The starboard is about 15 degrees hotter than the port, but that seems acceptable for now. I will keep a close eye on the temps when I run the boat tomorrow. This was just at a high and low idle. I have not pushed it to any rpm yet

I will give you a report tomorrow night.

Thanks again for all the help. I don't know where I would be if not for this forum.

Hope someone is around today.

I started the motor this morning, and it started right up instantly. I have not been to the lake to run it yet, but plan to in a few hours.

I have suspected that this boat had a charging problem from the first day I bought it, about 3 weeks ago now. First, the seller told me he just put a new battery in, and I could see it was new. And second, I measured the voltage at the battery with the engine off, and with the engine running, and the voltage is actually lower when the engine is running.

I have searched for a way to test the rectifier, and have come across many of Joes post, but I have not found one that give the instructions for how to test this. Is there an effective way to test the rectifier?

Also, if the rectifier is bad, should I even try to run the boat today?

As always, thanks for the expert advice.

OK, I followed this which I found in a service manual.

“Rectifier Test (All 3-6 cylinder
Except 1984-on 10-35 Amp Systems)
Refer to Figure 18 for typical location and test
connections.

1. Disconnect the rectifier leads at the terminal
board.

2. With the ohmmeter on the high scale, connect
one test lead to the yellow rectifier lead and the
other test lead to ground. Note the meter reading.

3. Reverse the test leads and note the reading.
The ohmmeter should read zero in one direction
and infinity in the other. If the reading is the same
in both directions, the rectifier is defective.

4. Repeat Step 2 and Step 3 to test the
yellow/gray lead.

5. Replace the rectifier if the readings are not
as specified.”

My ohm meter was set on 20k, and I got a reading of 700 on one, and 450 on the other. Both of these were only in one direction, and both were the same direction. I guess I am not sure what reading an “infinity” reading is? But I did get the readings above, so I assume the rectifier is shot.

I will not run the boat today. I am afraid to take any chances.

You did the test on an engine that was specifically "excepted"? Note it says "'84 on 10-35 amp systems" are not included for this test procedure. But anyway...to answer one of your questions....Infinity with regards to an ohmmeter reading means that the circuit is open, i.e. that no current can flow. Diodes flow current in one direction only. That is why the procedure says to reverse the leads...you reverse the polarity on the diode when you reverse the leads. On a good diode, generally speaking, you will show infinity (open circuit) when leads are one way, then reverse, and you will show some resistance reading, I cannot specify what you will show...it all depends on the diode and the meter. You cannot effectively test the reg/rect like you have with an ohmmeter. It is more complicated internally than just the simple diode test that you show above. What you CAN do is this: disconnect the two yellow wires, connect your VOM to the stator side of the wires. Set meter on ACvolts, and scale range to the next highest setting you have to say 30v. That would mean maybe 100v scale, or maybe 50v scale...depends again on your meter. Make sure the wires are not touching any block or metal parts, or each other, and start engine. You should read upwards of 30v AC at idle. It will have to be above 20 or so, to be barely adequate to work. Voltage will rise as engine accelerates. If you have very low volts, or no volts, then the stator is not feeding voltage and current into the reg/rect for it to do it's job. Another test you can do: Disconnect the big red wire attached to starter solenoid on the positive side (comes from the reg/rect). Set your meter on ohms reading, maybe 2k scale, and with engine OFF, measure the red wire to ground. You should not get any reading, (infinity or open). If you get a low reading, or zero ohms, you have a shorted output of the reg/rect. These tests are not the end-all of tests for the reg/rect, but they are a good starting point. You can run your engine all you want with the two yellows disconnected and insulated from each other and ground, just be aware that eventually the more you start it, the battery will go dead. So, start out with a fully charged battery, and I would even bring a spare. You would play he** trying to rope start that V6.

Every once in awhile, I make a post that I wish I could obliterate from the digital world. That last post was one of them.

I was reading, "Except 1984-on 10-35 Amp Systems" as "(Except 1984) - on 10 and 35 Amp Systems". I guess this makes a few of you chuckle, or at least mutter "what a dope". Admit it.

OK, so when we cleared the stator yesterday, all we did was clear it from being a problem. We did not actually prove that it was working properly. I understand now.

I will do those test tomorrow morning.

Also, I would die on the water before I would even consider trying to start this engine with a rope.

Thanks daselbee, don't give up on me!

crashkaloop said:

I have suspected that this boat had a charging problem from the first day I bought it now. With the engine running, and the voltage is actually lower when the engine is running. I have searched for a way to test the rectifier, but I have not found one that give the instructions for how to test this. Is there an effective way to test the rectifier?.

Click to expand...

The proper test that was outlined in the OMC manual years ago to test a water cooled voltage regulator/rectifier assembly (yours) was so involved, so complex, that I read it over closely three times, closed the manual, then devised my own test procedure as stated below.

Hopefully that rig has a tachometer. The tachometer gray sensor lead would normally connect to another gray wire that leads from the regulator/rectifier assembly to a terminal strip. When a tachometer is connected in this manner, and the regulator/rectifier is flawed, the tachometer will be quite erratic or will not work at all. The test to check the tachometer, which will at the same time reveal a failing or failed regulator/rectifier assembly follows.

BTW.... Your engine has a 35 ampere charging system under the flywheel.

(Testing Tachometer With Water Cooled Regulator/Rectifier)
(J. Reeves)

A quick check is to simply plug in a another new tachometer as a piece of test equipment. If the new tach works properly and the old tach didn't, obviously the old tach is faulty.... but usually boaters don't carry around a spare tach (see below).


A faulty rectifier wouldn't damage the tachometer, the tachometer simply wouldn't work. This is due to the fact that the tachometer operates off of the charging system and the rectifier converts AC voltage to DC voltage, enabling the charging system. A faulty rectifier disables the charging system, and the tachometer simply doesn't register.


However.... those water cooled regulator/rectifiers that are used on the 35 ampere charging systems (and some others) bring into play a different type problem, and as you've probably found out, they are really a pain to troubleshoot via the proper procedure. There's an easier way.


The tachometer sending/receiving setup operates off of the gray wire at the tachometer. That same gray wire exists at the engine wiring harness which is connected to the engine electrical terminal strip. You'll see that there is a gray wire leading from the regulator/rectifier to that terminal strip, and that there is another gray wire attached to it. That other gray wire is the wire leading to the tachometer which is the one you're looking for.

NOTE: For the later models that DO NOT incorporate a wiring terminal strip, splicing into the "Yellow Wire" mentioned will be necessary.


Remove that gray wire that leads to the tachometer. Now, find the two (2) yellow wires leading from the stator to that terminal strip. Hopefully one of them is either yellow/gray or is connected to a yellow/gray wire at the terminal strip. If so, connect the gray wire you removed previously to that yellow/gray terminal. Start the engine and check the tachometers operation, and if the tachometer operates as it should, then the regulator/rectifier is faulty and will require replacing. If the tachometer is still faulty, replace the tachometer.


If neither of the yellow wires from the stator is yellow/gray, and neither is attached to a yellow/gray wire, then attach that gray tachometer wire to either yellow stator wire, then the other yellow wire, checking the tachometer operation on both connections.


I've found this method to be a quick and efficient way of finding out which component is faulty.... the tachometer or the regulator/rectifier. It sounds drawn out but really only takes a very short time to run through. If the water cooled regulator/rectifier proves to be faulty, don't put off replacing it as they have been known to catch on fire with disastrous consequences.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay auction at:

http://shop.ebay.com/Joe_OMC32/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1

Hi Joe, Thanks so much for helping with this problem. I had actually read your procedure here: http://www.marineengine.com/boat-forum/archive/index.php/t-388624.html
I was trying to fix the tach, and had not really considered that I was also troubleshooting the rectifier until I was half way through it.

In trying to follow your directions, I must have done something wrong, or worse, the boat may be wired wrong. It is clear that the previous owner had a lot of equipment wired into the boat which is not there now. Anyway, while doing your test, I blew the main 20 Amp fuse that is in the engines wiring harness. I didn't even know it was there, and when the engine wouldn't even crank after I did the test, I was afraid that I had ruined my brand new Power Pack.

I found the fuse and replaced it, but was afraid to go any further with the test. It seems to me that the wires on my terminal are not quite as you described, and the owner may have jury rigged something in the past. I just cannot figure out why that fuse blew because I was slowly going step by step through your method.

I will revisit that tomorrow, and see if I can post some of the wiring discrepancies on the terminal strip that I mentioned earlier. I will try to make a diagram or something on what I have on the terminal strip after I trace some of the mystery wires. Then you won't have to waste so much time guessing what I have, and can better guide me.

I am sure you could take look at it and immediately know what was wrong, but I have to be slow and methodical. And without the guidance coming from you guys, I would be lost on all of this.

Thanks for all your help.

Just so you understand....stator has two separate functions. One is to power up the ignition system and the other is to provide charging power for the battery. When we "eliminated the stator" we were eliminating it as being the problem of your "no spark on one bank" situation. We were NOT even addressing any charging problem. Read the voltage on the two yellows. If around 30vac at idle, stator is good on the battery charging function too.

Well just great!!

Testing the stator was very easy, and very DISAPPOINTING!!

Idle = 5.4 VAC
High idle = 5.4 VAC

I guess this is shot too. I will start shopping for a new one.

Thanks Guys.

Seriously?? $500??

I know the price of copper is quite high now, but $500??

Is there any way to have these things re-worked or re-built?

Can anyone explain to me why the other test we performed on the stator showed good, yet it doesn’t work? I assume there are two primary components to this system. The stator, and whatever spins inside it to generate the AC, like an armature (I am guessing that it’s similar to a generator). Or maybe that function is handled by the timer base, which is slightly less expensive?

Is it possible that it is NOT the stator that is preventing the generation of voltage from the stator?

I explained above. There are two functions the stator performs, and they are separate and independent of each other. We were debugging "no spark on one bank". That is the ignition function of the stator. Your problems now are related to the battery charging side of it. When you get the bad stator off, examine it carefully. You will see that it is made up of many coils, and some of them are different from the others. Just be absolutely sure you did the test right. Yellows disconnected, measure the yellows on AC v scale, the yellow wires coming FROM the stator, NOT the yellows going TO the reg/rect, etc. I would shop around for a stator. EBay, many other suppliers sell them less than 500 bucks. This site doesn't let posts go thru that compete with it's own parts sales. CDI stator would probably be just fine. I would not get a used one, tho.