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2001 90HP Johnson "Piston Slap" & Cold Start Issues

J

Jeff Woodruff

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I have a 2001 90 HP Johnson. Recently I have had trouble starting after it was warm. It acts like a cold start, ie: I have to pump the fuel inline bulb, and hold the choke in for about 10 seconds before it starts, and that isn't always a guaranteed start. Sometimes it takes several tries. My mechanic tells me that is the ethanol evaporating from motor heat after I turn it off, and that I will always have that problem.

In addition to that, 3 weeks ago, while running about at about 15 mph down the ICW, it just died, almost like it ran out of gas. It did restart, like described above, but now with a loud tapping noise, which sounds like it is coming from the top of the motor. This tapping noise sounds relative to the RPM of the motor, I speed up: louder, faster tap. Oil level is full, the tell-tale is working. Again, the same mechanic, says that is "piston slap" or the piston hitting the rings. Unless I want to spend a lot of $$, then I have to live with it.

Last weekend, I went out again. Ran about 1 mile, the hot light came on, I shut her down and drift fished for about 45 minutes. Started back up, ran another mile, same thing. This happened 2 more times, each time with the same conditions. Finally, it ran without any piston slap or just dying out and no hot light for over 10 miles. Then it started happening again.

I am really confused as to what to think or do. Suggestions?

This motor has less than 200 hours on it. I'd hate to have to ditch it for another, but...

Help?
 
ICW? Where are you?

By the way, you have to start with the basics on this one. Compression, spark and then fuel.
 
daselbee said:
ICW? Where are you?

By the way, you have to start with the basics on this one. Compression, spark and then fuel.
Click to expand...

ICW is the Intracoastal Waterway. I fish in and around the Galveston bay system in Galveston, TX. Occasionally I use the ICW to avoid rougher water and others fishing to get to other spots within the bay system.

Explain what you mean "Compression, Spark, then fuel"please.
 
Yes, I know what the ICW is. I am on the east coast of Florida, you said ICW, and I thought if you were close, you could bring it by.
So much for that idea.

Three basic steps to start with in figuring out what is wrong. Do a compression test, do a spark test, and verify fuel is good and flowing properly.

There is too much wrong on your original post to even attempt to try to suggest a cause without knowing the results of the tests and inspections as listed above.

Your mechanic is iffy too, by the way. Evaporating ethanol....nah. Sorry, don't shoot the messenger.
I call it like I see it.
 
Compression & Spark test tomorrow. I will let you know the outcome. Thanks for the info you have provided already. Wish I was on the east coast of Florida. Gotta go 100 miles out to find water over 100 feet around here. Decent trout, reds, and flounder inshore around here though.

Thanks!
 
Uhh ...piston slap does not come and go unless its transferring aluminum to cylinder wall and tighting up hole....
 
Jeff Woodruff said:
2001 90 HP Johnson. I have trouble starting after it was warm. It acts like a cold start, My mechanic tells me that is the ethanol evaporating from motor heat after I turn it off, and that I will always have that problem.
Click to expand...

If this hard starting problem does not exist when the engine is cold, I'd suggest you take a long hard look at the stator under the flywheel (the beginning of both the charging and the ignition system). Look for two large black coils that are close together that might be starting to melt down, possibly dripping a sticky looking substance down upon the powerhead. Those two coils provide the AC voltage to the powerpack capacitor that is needed to energize the powerpack. When either of those two coils start to melt down, a voltage drop takes place that results in weak, erratic, and eventually no ignition. In this condition, when the stator is cold, it may function properly... BUT... when hot, the voltage drop comes into existence.

As "daselbee" sort of suggests, it might be a good idea to look around for another marine mechanic for a second opinion.

Jeff Woodruff said:
3 weeks ago it just died, almost like it ran out of gas. It did restart, like described above, but now with a loud tapping noise, which sounds like it is coming from the top of the motor. This tapping noise sounds relative to the RPM of the motor, I speed up: louder, faster tap. Oil level is full, the tell-tale is working. Again, the same mechanic, says that is "piston slap" or the piston hitting the rings. Unless I want to spend a lot of $$, then I have to live with it.
Click to expand...

Noise can radiate from a chipped gear tooth in the lower unit, up the driveshaft, then to the crankshaft... very difficult to pinpoint the noise location without a mechanics stethoscope. However, noise sources do not normally come and go... that happening is quite strange. It's possible that fuel wasn't being supplied properly momentarily resulting in the shutdown mentioned above... to test, simply have someone pump the fuel primer bulb constantly (acting as a manual fuel pump) which would force fuel through the engine's fuel pump. Your mechanic's remarks leave a lot to be desired!

Jeff Woodruff said:
Last weekend, I went out again. Ran about 1 mile, the hot light came on, I shut her down and drift fished for about 45 minutes. Started back up, ran another mile, same thing. This happened 2 more times, each time with the same conditions. Finally, it ran without any piston slap or just dying out and no hot light for over 10 miles. Then it started happening again. I am really confused as to what to think or do. This motor has less than 200 hours on it. I'd hate to have to ditch it for another, but... Suggestions?
Click to expand...

It's possible you picked up a plastic bag momentarily shutting off the water supply... BUT... if it were me, I'd be dropping the lower unit and dismantling the water pump assembly for inspection.

As "daselbee" suggests, the basic trouble shooting procedure is the way to go, first the compression test, than a spark test.

Compression test: Remove all spark plugs, check the compression. What are the actual psi readings of "all" cylinders?

Spark test: All spark plugs still removed, use a tester whereas you can set a 7/16" gap. The spark should jump that gap with a strong blue lightning like flame... a real SNAP! Does it? It would be good if you could perform this test when the engine is both cold and hot but it's not absolutely necessary. NOTE that the 7/16" gap is important!

*********************
(Spark Tester - Home Made)
(J. Reeves)

You can use a medium size philips screwdriver (#2 I believe) inserted into the spark plug boot spring connector, then hold the screwdriver shank approximately 7/16" away from the block to check the spark or build the following:

A spark tester can be made with a piece of 1x4 or 1x6, drive a few finishing nails through it, then bend the pointed ends at a right angle. You can then adjust the gap by simply twisting the nail(s). Solder a spark plug wire to one which you can connect to the spark plug boots, and a ground wire of some kind to the other to connect to the powerhead somewhere. Use small alligator clips on the other end of the wires to connect to ground and to the spark plug connector that exists inside of the rubber plug boot.

Using the above, one could easily build a spark tester whereas they could connect 2, 4, 6, or 8 cylinders all at one time. The ground nail being straight up, the others being bent, aimed at the ground nail. A typical 4 cylinder tester follows:

..........X1..........X2

.................X..(grd)

..........X3..........X4
 
You know....I see it all to often......I call it the "Baffle them with BS" method of diagnosis.

Throw out some "technical terms" like "piston slap" and "evaporating Ethanol" OR any other really exotic thing you can come up with. See if it sticks.

Enough of that.

Pull the flywheel and inspect for a possible loose stator hitting the flywheel magnets. Might be the problem.... Maybe if that is it, you can see pieces of metal and junk under the flywheel just be looking up under there. If so, expect large $ for repair parts.
 
Wow, guys...thank you all for the good advice! I am a high school woodshop teacher, so I called the auto mechanics teacher. He came over with his compression tester. We found 140 PSI in 3 cylinders, and 0 PSI in the 4th cylinder. At that point, I was so frustrated, we didn't do a spark or fuel test. I am going to try to find another mechanic and see if we should pursue repair or replacement.

Any suggestions? When 1 cylinder has no compression on a 15 year old motor, is it financially worth repairing?
 
Depends on whether you do the work yourself.-----Picked up a matching pair of 1998 loopers like yours.----came off the same boat.-------Dealer said ---" no time , not worth fixing "-------customer said---" we can not wait for repairs "-----------Installed a new set of motors.-----------Got the motors home and one had a hole in a piston and other motor had scored pistons.-----------Definetly worth repairing if you have time / patience and some tools.
 
Oh no!!! Worst news you could have gotten.

Do we have a model number? Looking it up by year and HP, it looks like a looper, so I guess the old "swelled water deflector" problem doesn't apply.

What is this motor? At any rate, this is bad news.
 
Yeah, worst news! This is a 90HP Johnson, Model #J90VLSIF. Does that sound right? Difficult to read. I certainly have the tools and the time. I could use some direction as to what to do, where to get parts, etc...I'm not asking for anyone to walk me through step by step, just point me in the right direction. My auto tech teacher buddies will probably provide some assistance, especially if they want to go fishing! But I don't want to rely solely on them. Any advice is greatly appreciated.

I did a little research on that model #. I can't find it when I look under the Boat Engine Parts on this site. The closest I have found is J90VLSNF. I went and looked at it again, took a picture, even had the wifey confirm I wasn't blind. It does say J90VLSIF on the tag mounted on the transom bracket. I would share the picture but can't see how on this forum.
 
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Just out of curiosity, did you ever use ether based starting fluid to try to get her running?

Advice, get a factory service manual. Part number 787120. Ebay is the place but unfortunately there are none now.
 
Never have used ether starting fluid for anything other than setting the bead on a tire. I have a Clymer Outboard Shop Manual. Can't find that part # anywhere? I'm also conflicted about the Model #, It doesn't seem to match any that I've found for '99-'02. The V digit is the sticking point, everything else matches. Am I to assume that many parts are interchangeable from year to year, within reason of course.
 
Jeff Woodruff said:
This is a 90HP Johnson, Model #J90VLSIF. . I would share the picture but can't see how on this forum.
Click to expand...

J90VLSIF...... OMC's code is the word "INTRODUCES" whereas each letter stands for a number from 1 to 0. The "SI" within that model number indicates that the year is "01" (2001)

J = Johnson
90 = Hp
V = ?
L = Long shaft
S = 0
I = 1
F = Factory run number

It should be quite easy to insert a image/graphic/picture here. At the top area of this reply window, 3rd icon from the right, let your cursor hover over it, it'll state "Insert Image"... click on it.

If for some reason, your computer doesn't read the same as what I'm looking at... visit the site "Photobucket", a free program... that'll do it.
 
I am not finding a problem with the "V". I see that in the model numbers.
I do not see the "F" on the end. That's the one I cannot see.
Look at shop2.evinrude.com, select Johnson, and then drill to J90VLSIC...that will be the list you should use.
Under the literature section, the service manual is as I posted above.

As Racer says....ignore. The engines are basically the same and you will not have trouble getting your parts.

I thought about this last night. You wanted some pointers.....here is one.
The fact that this is a saltie.....you will likely have a very hard time with the bolts. Be prepared to have to drill out broken bolts.
I know you didn't want to hear that, but I work on saltwater engines all the time, and that is the biggest problem I find...getting them apart.

Get a MAPP torch and do not be afraid to use the heat.
 
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