1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

another todd

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Jul 11, 2009
Messages
38
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

OK This is a different set up from what I described. Sorry. What seals the water jacket at the thermostat?

Oh I see it now, another o-ring.
 

HybridMX6

Senior Chief Petty Officer
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Oct 22, 2008
Messages
676
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

Yeah, it's different from mine too. I didn't know until I pulled up the schematic online.
 

spencroy

Petty Officer 3rd Class
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86
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

Hey Guys,
Thanks so much for all the advice so far, there is a lot to digest here.

First off to Joe's point on which specific cylinder I am talking about. Using Joe's example:
Port - Starboard
2...........1

4...........3

6...........5

The port where I have 0psi (if I am not an idiot and did a bad test) is 6. The two cylinders I am using for comparison are 2 and 4.

Thanks so much for the picture advice, I will be getting home this afternoon and I will try to get some better pics.

Todd, to your points: I am not sure what a reed valve is. would you mind giving me a little direction on that? I was really hoping the compression would be at the blue ring vs the yellow as that causes me to fear the nicks in the piston edge are the root cause.

Hybrid, thank so much for the diagram. I have been struggling on brp trying to come up with that, that diagram will go a long way in helping me point you guys to what I am talking about short of "brass bolt" etc :)
In addition, the o-ring seal itself does appear to be complete, unrotted, and in tact. The only thing I can tell different about it compared to cylinder 2 and 4 is it may be slighly flatter. I will try to get better pic evidence (using the Macro tip).

I will also take your guys advice on putting the head on glass and checking for wobble. Will post as soon as I can.
Roy
 

ezeke

Supreme Mariner
Joined
Sep 19, 2003
Messages
12,532
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

Good or bad, the reeds will have no effect on compression reading.

You need to get the cylinder head off and inspect. You don't have gaskets, you have o-rings on your cylinder heads but they could be leaking.
 

spencroy

Petty Officer 3rd Class
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Sep 26, 2007
Messages
86
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

Hello Guys,
------------------------------------------------------------
Short version:
1. there is no wobble when placing the head on a glass desk
2. I can still not convince myself of o-ring failure
3. The head gasket for cly 6 was not pressure washed, nor was the piston
However, the cylinder was cleaned with b-12 cleaner, but I do not recall
cleaning the head with that cleaner, but I may have to try and inspect for
damage.

current theories:

theory 1 - the 'ridges' on the edge of the piston made contact with the head
and broke the seal between the head and o-ring

theory 2 - whatever caused the damage to the piston edge is much worse
deeper in the cylinder bellow the piston top and piston edges. the two
seals on the piston itself may be badly damaged and that is where I am loosing
compression.

current plan-o-attack:

Since theory 2 suxs, thinking of starting with the o-ring since its cheap.
Borrow a drimmel or sand the metal
edges from the top of the piston in cyl 6 with the piston in the fully
out(up) position. Carefully cleaning all metal shaving etc, lowering the piston,
making sure completely clean. reinstall with new o-rings, retest compression.

However, I will need to understand what caused the 'ridges' on the piston
edge as I am worried this what Joe Reeves was talking about when he
said "spells trouble with a capital "T"
------------------------------------------------------------

Long Version:
Guys I am sorry I lack the ability to be concise. However, I did manage a
couple of decent pictures describing the o-ring and why I am struggling
to suspect it, and the 'ridges' which have me concerned.

Didn?t get home last night till after dark, so the only test I ran was to
verify the "wobble" per Hybrids suggestion. I have a glass desk in the
shop, so I laid the head on the desk, and could detect no wobble. It felt
flush and firm when I tried to get it to rock back and forth. The head
appears not to be damaged or warped.
######################
compression question 1
To hit back on the question I was asking earlier and was answered but I am
still struggling with understanding. I am going to try to use a very crude drawing
to help me illustrate my question.



What I am trying to get straight in my mind is where is the piston located at the moment the spark plug fires. This is in an effort to better understand the root cause of my problem.

Case 1 in the diagram: Based on the "wear" at the top of each cylinder there appears to be a line on all 3 about 1/8th of and inch down from the top. This leads me to suspect that this is the location where the spark plug fires and presses the piston back down. If this is the case it may indicate that my piston seals are suspect along with the o-ring seal between the head and the block.

case 2 in the diagram: The piston head is curved, the head is curved and then bells up at the spark plug. case 2 would be the piston lifts to its maximum length before the spark plug ignites. Why I think may be possibly the case is it would explain the compression loss if, the build up of the 'ridges' on the piston edges reached a point where the piston was forced upwards, the 'ridge' pushed the head just enough to break the seal between the o-ring and the head (the o-ring was pressed in position since 1993 and did not expand when/if the head was pushed). The two major hurdles I have to this case though are:
- if that is true, why is the 'ridge' not beat flat, and why is there not obvious evidence of damage on the head surface.
- no evidence of o-ring seal failure either as its mounted on the block, or on the head surface (as far as I can tell anyway)

... to be continued
 

spencroy

Petty Officer 3rd Class
Joined
Sep 26, 2007
Messages
86
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

...continued

######################
The 'ridges' on the piston edge.
The following set of photos will demonstrate why I am having problems putting the fault on the o-ring, and will give the best view of the 'ridges' on the piston edge which I keep referring to.

About the best overall picture I was able to manage would be this one:
(click for larger)



As you can see, there is nowhere on the o-ring itself that I can associate any specific fault. All in all to the untrained eye it seems ok to me.

The next focus then will be the only thing I can find different about this specific cylinder. With the piston in the up position the piston does not budge side to side, nor down when I try to move it by hand. The only thing I can see different about this piston are the 'ridges' as seen in the following:



The damage seems to be about 3 o?clock, 5 o?clock, 8 o?clock and 11 o?clock

3:00


5:00


5:00 and 8:00


11:00


So, naturally my first question is:
Question 1. What caused this?

In my mind this has to be a bi-product of either heat or friction.

So who is the idiot who rebuilt the VROII? - umm.. that'd be me
an who is the idiot who rebuilt the water pump? - umm... also me.
so there is a whole lot of potential blame here on me.

Question 2. Because I suspect all seals at this point, is there an opposite of a compression test to somehow verify the seals on the piston? I cant think of any way to accomplish this.

Question 3. Is there any solution for this problem of 'ridges'? I lack the skillset (and the cherry picker) to actually pull off that upper, and so replacing that piston is certainly in the worst case scenario. However, if the head is ok, and the o-ring is ok, then that only leaves the two piston seals as the potential failure point.
Whatever caused the damage to the piston edges may have been something banging around in there and it may be blow those piston seals as well. However, loosing all my compression through the side of the piston walls seems a little less likely than through the head gasket o-ring (I would expect to have some compression if that was the case).

The only idea I have is to try and scrape/sand off the 'ridges' and slap her back together.

The problem I have with this idea is that I have done nothing to address a problem here, I am simply reacting. I don?t feel like I have a handle yet on what caused this.
 

spencroy

Petty Officer 3rd Class
Joined
Sep 26, 2007
Messages
86
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

And finally....
Here are all pictures that I took today.
http://s305.photobucket.com/albums/nn227/spencroy/Cajun - 150/cyl-6/?albumview=grid

I didnt do to well on Joe's request of the cylinder down pictures. About the best one I managed was:


If there is something specific down in there I can be after let me know (an angel or something that will show what your after better?)

Any advice/suggestions/"for the love of all that is good don't do that" would all be appreciated.
Roy
 

spencroy

Petty Officer 3rd Class
Joined
Sep 26, 2007
Messages
86
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

double post removed.
For some reason I have had problems with response time from the fourms for the last couple of weeks. It seems only on i-boats where I am having any problems. Am I the only one seeing that?
 
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HybridMX6

Senior Chief Petty Officer
Joined
Oct 22, 2008
Messages
676
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

To be honest, from the locations of all those marks, I'm wondering a couple things.
1: How long have you owned this engine?
2: Has it ever been rebuilt as far as you know? If so, when, and to what extent was it done?

I'm asking b/c given the position (clock-wise) of those marks, they seem like right about where the ports are (and look like it too from that last pic). If the engine has been worked on before, and someone unknowledgeable did the work on the block (i.e. honing it or boring it over), they were probably unaware you are supposed to "chamfer the ports" on outboards. This means you knock off the sharp edge to the port after honing or boring, so the piston top and rings won't catch on it. It looks like the piston has been catching on the ports, which could also lead to complete ring failure, although usually you would see a LOT more piston damage if that were the case. But, if only a small piece broke off, you may not be able to feel the difference due to most of the ring being intact, but enough could be missing to cause 0 PSI.
I am not too familiar with your engine, but from other posts I have read regarding how to check the rings, you may be able to pull off the exhaust or something to inspect them. Not sure if your engine has this as I don't see it in the schematic, hopefully someone else with more knowledge of this engine can answer that.

As for a reverse compression type test, you can see if you can borrow a leak down tester, but you need an air compressor also if you are going to do it. You hook it up similarly to a compression test, but instead of turning the motor over to build compression, I believe you use the compressor to feed air into the cylinder, and then you measure how much it drops over a period of time. I've never done one myself, but have heard of it and heard it is better and more accurate than a compression test.
 

spencroy

Petty Officer 3rd Class
Joined
Sep 26, 2007
Messages
86
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

Hybrid, to your points.
1. I have only had it since april of this year
2. I am not certain, the story I was told did not include a rebuild, but not 100% sure if the seller can be trusted.
If she was bored, it would appear to me all 3 cylinders were, as they all appear to be identical in size.

------------------------------------------------------------------
***brief history, well brief for roy... ***

purchased her in April 2009 from the widow of the old man who owned it.
The boat was not running, and had been sitting outside for the last 2 years (since the old man's death)
The story was that the old man bought it new in 1994, used it for about 10 months and then developed heart disease which eventually killed him in 2004. The boat sat in the garage from 2004-2007, and then was moved outside. The story went that the boat was like new, and had perhaps 50 hours on it (however, it had a couple problems and would not run so the family wanted rid of it.)

I gave them to much for it, but liked the idea of moving from my 77 115 to a 93 150 and started in on it.

To your point though Hybrid, I do not know if the engine was rebuilt. However, due to many little things I seem to find about how clean this engine is, I do ocassionally think the seller may have not actually lied (although not certain) and this may be a fairly low hour engine. For example, there are little stars punched into top of each piston which even lightly coated with grit in cylinder 2 and 4 I can clearly see. The problem cylinder 6 is so clean I can read etching in the piston.

To get her going I had to debug a short in tilt/trim:
http://forums.iboats.com/showthread...p://forums.iboats.com/showthread.php?t=307666
and got her on the water for her maden voyage on Mothers day and had no major problems.

Took her out camping a few weeks later and with the entire faimliy on board after almost a full day of boating while idling through a cove the alarm began to burst every few seconds, and then started solid. Having read the manual I realized this was overheated and trolled our way back to camp. I replaced the entire water pump as a result, and have not had those alarms go off since. The impeller was damaged by (you guessed it .. me) when I launched on the camping trip. The drought is so bad on lake travis that all the ramps are now out of the water, and I had launched into the main lake off a sandy beach. Not paying close enough attention I did not troll her deep enough and apparently sucked some sand into the impeller when I started up. That sand took only a couple hours to cause some pretty obvious damage.

However, since then the rig has been a joy. She is fast and has not had any other problems till this recent bout. I have had her fishing many times, and other than trolling motor problems she fires up on the first try every time.
----------------------------------------------------------------------

I will look into that leak down tester and that is an interesting point you bring up about the exhaust. I am going to take another look at that engine from the back and see if there may be some way to accomplish getting a view of those piston rings via the exhaust.

Thanks
Roy
 
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HybridMX6

Senior Chief Petty Officer
Joined
Oct 22, 2008
Messages
676
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

You wouldn't be able to tell if one has been honed at all, and it'd take a very skilled eye to catch one that's been bored. We're talking the 1st bore size is only .020" over. Honing it wouldn't change the size hardly at all, so doubtful the naked eye would be able to tell. If you had (or coulde borrow) a measuring device for that, you could check it against whatever the actual bore is supposed to be.
I tend to believe people myself, but often find their story is half true, half lie. Not saying yours is, but who really knows?
Like I said, I didn't see an exhaust cover on your engine's schematic, so it may not have one, and what I had mentioned may not pertain to your engine. My 1993 60hp 3 cyl. has one (although come to find out, it's really a 1992, another lie from previous owner, who originally told me it was a 1994).
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

Spenroy.... Excellent job on those pictures. I can plainly see the piston damage as well as the cylinder wall scoring. Unfortunately, you are looking at a major overhaul job. Although the damage may be only to one cylinder, the entire engine must be dismantled due to the cleaning that will be involved, and the machine work that must be performed........ boring that damaged cylinder oversize by at least .020 to accompany a new .020 O/S piston & ring set.

I doubt that this was caused by anything you did, but rather something that wasn't done by you and/or the previous owner (this happens frequently).

The damage I see would normally be caused by improper lubrication due to the related carburetor being somewhat fouled, gummed, clogged. This results in a lean running condition of the related cylinder that the aluminum piston running up and down the steel cylinder won't tolerate.

Bottom line choices..... Rebuild, trade up, quit boating.
 

jonesg

Admiral
Joined
Feb 22, 2008
Messages
7,174
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

The vertical lines in the cyl bore are the signs, the cross hatch is gone.

Get the manual if you don't have it,
www.outboardbooks.com
Dismantle it and have a marine machine shop bore and fit an oversized piston for you.
 

spencroy

Petty Officer 3rd Class
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Sep 26, 2007
Messages
86
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

the only words in the English language that can explain how I feel right now are all outlawed on the boards... $#!#$!

oh well, the "quit boating" is really starting to appear the cheapest and most atractive alternative at the moment. Looks like I am going to be off the water for a while.
Thanks so much for helping me figure out where the problem was. I hope to post sometime this year with the results of the rebuild (although currently I hope to save the money up and have this done by a pro).

I am guessing the entire rebuild by a shop would be 2500-3000 range (perhaps more), but just to get a rough number in my mind, can anyone put forth an estimate on what it would cost if I did the disassembly and only took the cylinder to be bored and the oversized piston fitted?

Roy
 

HybridMX6

Senior Chief Petty Officer
Joined
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Messages
676
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

If you do it all yourself and have the machine shop hone/bore the cylinders, and for good measure at least replace the rings on the other cylinders, I'd imagine you are looking at around $1000, assuming just that one cyl. is in need of major work. You will need some assorted parts, like powerhead gasket set for example, and I'd have to suggest doing the water pump, rebuilding carbs, etc. while it's all apart anyways, it'll save you time and money in the long run.
 

jonesg

Admiral
Joined
Feb 22, 2008
Messages
7,174
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

the only words in the English language that can explain how I feel right now are all outlawed on the boards... $#!#$!

oh well, the "quit boating" is really starting to appear the cheapest and most atractive alternative at the moment. Looks like I am going to be off the water for a while.
Thanks so much for helping me figure out where the problem was. I hope to post sometime this year with the results of the rebuild (although currently I hope to save the money up and have this done by a pro).

I am guessing the entire rebuild by a shop would be 2500-3000 range (perhaps more), but just to get a rough number in my mind, can anyone put forth an estimate on what it would cost if I did the disassembly and only took the cylinder to be bored and the oversized piston fitted?

Roy

For many of us, the reason we are here , this is the only way we can afford boating, its DIY or forgetaboutit.
 

HybridMX6

Senior Chief Petty Officer
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Messages
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Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

For many of us, the reason we are here , this is the only way we can afford boating, its DIY or forgetaboutit.

Agreed. If I had to pay a shop to do my water pump and rebuild carbs, I wouldn't be boating for a few months at least as I don't have the money. As it is, I got all the parts off ebay for a total of $70, complete water pump repair kit and 2 carb rebuild kits.

It may be an easier/cheaper option for you to look around for a used motor with a good powerhead on it, or just a used powerhead. Not sure what's out there for used, but it never hurts to look around.
 

Faztbullet

Supreme Mariner
Joined
Mar 2, 2008
Messages
15,664
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

A word of warning.. OMC had problems with this engine block leaking water internally and several service bulletins issued on this. I will not rebuild a 60 degree 150/175 unless block is pressure tested. I rebuilt one that showed no leaks but crapped out 3 months after rebuild due to it started leaking(ate it) Here is what Mar-fab has on this:
http://www.mar-fab.com/MarFab_Tech_Bulletins_D9579.pdf
 

spencroy

Petty Officer 3rd Class
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Messages
86
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

Hello Guys,

I wanted to provide a quick follow up on this one.

Short Version: $3807 for my local shop to rebuild.

More Detail. Natrually anyone on the this forum is going to think (check that know) I paid a bit to much. I agree that if I had shopped more agressively, or had only had the cyls done it would have been much more affordable, but I thought I would try to buy some peace of mind. I have had the boat back for 6 days, had her on the lake 2 times alread (its cold in austin, but not cold enough to keep me from fishing now that I have her back).

Summary of major changes:
2 cyl rebored and block rebuild
carbs rebuild
gas/oil tanks drained, lines replaced

root cause of engine failure:
water in oil (or other words I am a dumb@$$ and the shop bill is pretty much just regular old karma) water was in the gas tank as well.

Did I have the rebuilt block pressure tested based on the previous post? No, I forgot about that till I came out there to update.

Thanks for all the advice and suggestions in this thread in helping me understand what the failure was, and what my options were. I am just so happy to finally be back on the water!
Roy
logo2.jpg
 

HybridMX6

Senior Chief Petty Officer
Joined
Oct 22, 2008
Messages
676
Re: 1993 Johnson 150 - Did I blow a cylinder or worse? (based on these symptoms)

Well, at least you got her back on the water, know what happened and how to avoid it in the future (perhaps a fuel/water separator would be a good investment), and did it for way less than a new motor would have cost ya.
 
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