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terry

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Is it possible to replace a p

Is it possible to replace a piston on a 1980 115 V4 Johnson outboard without pulling the crankshaft? I have at this point separated the crankshaft and the powerhead and removed the problem piston and would like to know if you have to replace the upper and lower crankshaft seals when going this far....
 
At least replace the bottom s

At least replace the bottom seal. The upper can be replaced by pulling the flywheel at any time.You need to remove the 4 inner screws on the bottom bearing housing and the outer screws. Might as well replace the bottom roller bearing as cheap insurance. Good luck
 
"Terry.... If you had to repla

"Terry.... If you had to replace a piston, I would strongly suspect that it has damaged the cylinder wall. If so, simply installing a new piston will result in the damaged wall destroying the new piston.

Joe
"
 
" Mr.Joe. What would be the re

" Mr.Joe. What would be the recommended gasket sealer to adjoin the crankcase and the cylinder block, and also is this material(sealer) under the upper and lower crankcase heads??? Also do you know of a site on the net where the replacement parts that I will need for the 115 Johnson would be the cheapest??? Thanks!!! "
 
"Terry... The crankcase and th

"Terry... The crankcase and the block are one and the same. However, it's usually refered to as the crankcase. The sealer that goes between the halves is a red substance called "Gel Seal" which actually hardens and seals with the "absence" of air. The company "Loctite" also manufactures this substance under its own name... Loctite, and is called Gasket Eliminator 518. Along with this name, it is also marked Item No 51831. It should be available at most of the automotive type stores in a 1.69 Fl Oz tube..

Pertaining to the upper and lower crankcase heads, use only grease which is to be applied to the "O" Rings.

Where the most reasonable parts might be obtained is something I don't know, but possibly someone else will jump in here to answer that one. I do have some parts left in stock which might possibly be of some use to you. List exactly what you need via e-mail and I'll see what I can do.

Joe
"
 
" According to the serial numb

" According to the serial number on my Johnson 115V4 outboard it is a 1980 model..According to the repair manual I am using as a reference for cylinder replacement this outbard year is pre needle bearings (loose) for the wrist pin assembly,but mine has the needle bearings and not the preassembled bearing.. Are the two types of bearing setups interchangable?????? "
 
"Terry.... Yes, you can use ei

"Terry.... Yes, you can use either type wrist pin bearing setup. The assembly with the permanent needles is the latest one. I also wanted to add to my above post.... If your crankcase is the type whereas the halves joins together via a metal to metal surface, then use the "Locktite Gel Seal" substance. However, if your crankcase has the rubber spaghetti seal that lays in a groove within one side of the crankcase halves, then use "Marprox Sealer #1000". Note that "Marprox" makes other sealers... use only the #1000.

Joe
"
 
Does anyone have an idea wher

Does anyone have an idea where I may find a .020 oversized piston and ring kit for a 1980 Johnson 115 V4. Can't find one locally... Woe is the man that has an OMC product after the bankruptcy!! HA. HA.
 
"Terry,
First I tried to e

"Terry,
First I tried to email you directly with this info, but your email address did not work, so I will provide the info here.
I can supply you with that piston in either a Wiseco(80.00), A Sierra(85.00), or a Pro(85.00). I prefer the Wiseco as it is a forged piston as compared with a cast piston, however the original pistons are a cast. All are piston kits which include piston, rings, wrist pin and circlips. The price does not include shipping, which should be less than 10.00 in the US. Let me know if interested. In addition I can supply all other needed parts to rebuild that engine-gaskets, seals, rings, bearings etc.
E-mail me directly if interested to keep this forum open to others.
[email protected]"
 
" Mr. Joe,
This is Terry a

" Mr. Joe,
This is Terry again with the 115V4 Johnson that peeled the ring on the piston due apparently to a water intrusion in that cylinder. On inspecting my head today, I noticed that a two inch piece of gasket material was affixed to the mating surface of the head just above the slots for the water passage. The head gasket itself was smooth and clean at the surface point of this material on the head itself, not a left over from the head gasket that was or is on the motor. Do you think that this could have been the culprit as in the surfaces between the head and the block could not possibly have mated smoothly??
Thanks for your input.. "
 
"Terry... Yes, a piece of fore

"Terry... Yes, a piece of foreign material (something that does not belong there) such as that would certainly create a problem. It would, in effect, act as a spacer which could (and most likely did) allow water to pass across to the cylinder. It would be my guess that someone at one time or another installed a new head gasket and did not catch that stuck on portion.

Joe
"
 
" Mr. Joe,
Terry again. I o

" Mr. Joe,
Terry again. I ordered my replacement piston kit along with a new wristpin bearing assembly. What type of grease in particular should I pack the bearing assembly with, if it matters. I also would like to ask you what type of gasket sealer should I use when reassembling the Johnson V4; other than the type sealer you told me about for the crankcase halves?
Thanks for your indulgence. "
 
"Terry.... It really doesn&#39

"Terry.... It really doesn't matter what type grease you use on that bearing. The fuel/oil mixture running through the engine will disolve the grease quite quickly anyway.

Pertaining to what type of sealer to use on the gaskets... use the gasket sealer that comes in a can that has a brush attached to the screw on cap. It's simply called gasket sealer and would be available at any automotive type store. Good luck.

Joe
"
 
" Mr. Joereeves,
Mr. Joe,

" Mr. Joereeves,
Mr. Joe, 'tis Terry again with the '81 Johnson 115V4 that threw the back ring on the bottom right cylinder. Should I use the gel seal on the flange edges of the upper and lower crankcase heads when I join the crankcase halves together, as I did not remove the crankshaft??? Also as I was cleaning out the exhaust area of the motor after removing the water and exhaust plate, I noticed that the tops of the pistons on the right side of the motor (side that I lost the ring on lower piston) are cleaner (less carbon buildup) than the left side. Any suggestions as to why or is it just that with the compression loss of the missing ring I was not drawing as much fuel and oil mixture to that side???
Thanks for your expertise!! "
 
" Mr. JoeReeves,
Terry aga

" Mr. JoeReeves,
Terry again! I thought that I read in my repair manual on the JohnsonV4115, upon honing the cylinder I was supposed to go back with a certain grit of emery cloth to finish the cylinder wall. I can't seem to find it upon review of the manual. Is this an accurate assesment of cylinder wall finishing or am I daydreaming????????
Thanks!!!!! "
 
"Terry.... I don't recall

"Terry.... I don't recall ever hearing of that procedure. Use a fine grade hone to deglaze the cylinders and when about finished, slow the drill down to a slow speed and run the hone up and down the cylinder so as to give a criss crossed appearance to the sleeve. This will assure a perfect seal between the rings and the cylinder wall.

PS... Just to be sure, I checked my manuals. There's no mention of using a emery in my manuals either.

Joe
"
 
" Mr. Joe,
OOPS! Do you thin

" Mr. Joe,
OOPS! Do you think that medium grit stones are to rough to hone cylinder? That was the stones I had on the hone, but have not sealed the crankcase halves yet, so removing the piston and re-honing the cylinder is not out of the question, but a delay in process.
Thanks,
Terry (OMCV4) "
 
" Mr. Joe,
I also used ga

" Mr. Joe,
I also used gasket sealer (OMC) on the reed valve assembly gasket. I would like to know if that was ok or should I remove or replace the gasket???
Thanks,
Terry (OMCV4) "
 
" Mr. Joe,
What is the thre

" Mr. Joe,
What is the threaded nipple plug for the by-pass hoses called. The top one on the reed valve assembly is broken at the tip and I need to know what it is called to facilitate access through a parts supplier. Sorry for being a pest..My repair manual does not list the part at all..
Thanks,
Terry (OMC115V4) "
 
"Terry..... You should only us

"Terry..... You should only use oil on the leaf plate (reed) gaskets and the intake manifold gasket. The gasket sealer may interfere with various fuel passages.

The medium honing grit will probably be okay. If the cylinder wall feels fairly smooth, I wouldn't be concerned about it.

You asked about "the threaded nipple plug for the by-pass hoses". I can't place what you're speaking of at the moment. The alarms are set right now so I can't get at the books. However I've made a note of that item and will check into it in the morning and get back to you.

Joe
"
 
"Terry.... Those aren't &#

"Terry.... Those aren't "By-Pass" hoses, they're fuel recirculating lines (hoses). The intake manifold has four (4) recirculating valves that the hoses attach to, and I assume that what you're saying is broken is one of those valves. When they were first manufactured, they were made of some kind of plastic or nylon material. They were improved and are now made of brass.

The OMC part number is 392988 and is called a "Recirculating Valve". A rough guess of their price would be in the area of $15.00 apiece.

Joe
"
 
" Mr. Joe,
Terry again wi

" Mr. Joe,
Terry again with the V4 115 Johnson that I am trying to rebuild myself. Is there a repair manual that shows a schematic or diagram that shows the routing of the fuel recirculating hoses and the wiring hornesses coming from under the flywheel. I have reconnected all the hoses and wires as I had them all marked but the routing leaves a lot to be desired. The repair manual that I have "Evenrude/Johnson ourboard shop manual" makes no reference to the routing of either. Is there another more current book that you know of that would have them, preferably in pictures, As I am quite the unskilled mechanic!?Ha!Ha! Thanks for your help. Terry "
 
" Mr. Joe,
Terry again wi

" Mr. Joe,
Terry again with the V4 115 Johnson that I am trying to rebuild myself. Is there a repair manual that shows a schematic or diagram that shows the routing of the fuel recirculating hoses and the wiring hornesses coming from under the flywheel. I have reconnected all the hoses and wires as I had them all marked but the routing leaves a lot to be desired. The repair manual that I have "Evenrude/Johnson ourboard shop manual" makes no reference to the routing of either. Is there another more current book that you know of that would have them, preferably in pictures, As I am quite the unskilled mechanic!?Ha!Ha! Thanks for your help. Terry "
 
" Mr. JoeReeves,
Terry agai

" Mr. JoeReeves,
Terry again. I have a question that I may not be able tio accurately describe, but will try anyway. Upon reassembling the stator/timerbase assembly, I noticed that the spark advance control rod assembly moves in somewhat slow motion behind the full advance of the trottle arm, like the spark advance would be late at full throttle. Does this make sense or have I (which I suspect) have made a mistake in reassembly????
Thanks for your input... "
 
" Mr. JoeReeves,
Terry agai

" Mr. JoeReeves,
Terry again. I have a question that I may not be able to accurately describe, but will try anyway. Upon reassembling the stator/timerbase assembly, I noticed that the spark advance control rod assembly moves in somewhat slow motion behind the full advance of the trottle arm, like the spark advance would be late at full throttle. Does this make sense or have I (which I suspect) have made a mistake in reassembly????
Thanks for your input... "
 
"Terry..... That timer base is

"Terry..... That timer base is held to the top bearing assy with four (4) s/steel "L" clamps. If even one of those clamps is too tight, the timer base will stick. This will cause the engine to fall on its face (so to speak) when throttle is applied. If this is the case, to find which one is causeing the problem, use a long skinny screwdriver to gently lift each clamp (one at a time) while moving the timer base nylon retaining ring. If the clamps are okay, I'd suspect that the bearing surface of the timer base, or that of the top main bearing, is not as clean as they should be.

Joe
"
 
" Mr. Joe,
Hope you are w

" Mr. Joe,
Hope you are well, 'tis Terry again(115V4). I cranked the motor today and it was a little slow in starting, but eventually did. As it warmed up the idle fell off until I would step it up with the carb linkage to a higher idle, then it would hold a little bit and then fall off again to the point of stalling. In as much as I did not move the advance stop adjustment screw in the one piston rebuild is it advisable to have a mechanic check the timeing?? I did not use new spark plugs in this initial start, but intend to use new ones Friday, my next day off... Any suggestions!!!
Thanks much... "
 
" If you didn't move the f

" If you didn't move the full spark advance screw (the one with the rubber boot), and it's locked solid, I wouldn't be concerned about it. "
 
" Mr. Joe,
Terry again suff

" Mr. Joe,
Terry again suffering from major depression. Took the boat out today to try motor and it cranked and ran fine for about 20 minutes and then it fell on it's face just like it did before when I lost the piston(115V4). It would not accept any throttle from console, but accepted high warm-up lever rpm's with no hesitation. Idled back to dock and after about 5 minutes the engine surged once and at that point would accept throttle. I suspected piston loss as before but at home the compression was 135+ on all cylinders.
Thoroughly confused, do you have any suggestions??
Thanks,
Terry "
 
" Mr. Joe,
Clarification on

" Mr. Joe,
Clarification on the 115V4 compression readings. After warming the engine and with open carbs as per manual, I had about 144lbs of compression per cylinder. Upon removal all spark plugs looked the same but the two on the right side seemed to be warmer to the touch than the two on the other side...
Thanks,
Terry "
 
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