Poppit valve on an early 90s Merc 115

[palewis]

The mechanic tells me the poppit valve is gone and that the 5 bolts that need to be removed are siezed. His rec. is that I replace the motor -- his temporary fix is to cap the leak... Can I run the motor that way for long?<br /><br />Any suggestions on how to back the bolts out without snapping them? I can't afford a replacement.

 

[andy6374]

Re: Poppit valve on an early 90s Merc 115

Here's a suggestion, find a new wrench.<br /><br />The bolts might snap...so what. Drill them out, slip in some heli-coils or time-inserts, put in some new bolts (grease the bolts up) and take the boat for a ride.<br /><br />Just remember to replace the poppet assembly while you are at it

 

[TxShorty]

Re: Poppit valve on an early 90s Merc 115

Good suggestion on finding a new wrench!! <br /><br />I have to ask, though, what is the condition of the motor otherwise? Might there be some other reason for this very extreem solution?

 

[palewis]

Re: Poppit valve on an early 90s Merc 115

Thanks for this.<br />The motor is in good repair. The mechanic said they don't drill out bolts, that we'd have to pull the motor and ship it to town, have it drilled there, etc., etc. He has the only machine shop around. <br />Any thoughts on how long I can run it with a cap on the valve? The pressure has gone from 7.5 to 11.5 with the cap on.

 

[andy6374]

Re: Poppit valve on an early 90s Merc 115

Do you have a power drill? Then you can drill the bolts out if they break. Dewalt pilot point no-slip shank are the best. Get a heli-coli kit and you will be good to go. <br /><br />Forget the wrench! Obviously this is one of those shops that says "We don't work on boat from before 1996" (i.e. we don't do anything). You can do it.

 

[palewis]

Re: Poppit valve on an early 90s Merc 115

Does anyone have any idea about how long I can run this with a cap on the valve -- I don't think I'll be able to get to fixing it for a couple of weeks.

 

[andy6374]

Re: Poppit valve on an early 90s Merc 115

you can run it until it burns out if you choose.<br /><br />I wouldn't use it until it is properly working.

 

[grandall]

Re: Poppit valve on an early 90s Merc 115

If you can get a fine propane torch flame on the bolt head try heating and cooling the bolt no less than three times, cooling it down with WD-40 (Be careful of fire). Three times is the magic number. Then heat it again and work it gently back and forth in small increments with a six-point socket. Don't over torque it! I've had good luck with this technique on outboards and have only had it fail on very old tractor exhaust bolts. Like most things in life, you must be patient, gentle, and think good thoughts. If it starts to turn and quits then repeat the process. Once you can get WD-40 under the head don't be afraid to let it soak overnight. <br /><br />Talk to a car restorer or good automotive mechanic about removing the bolts. Extracting or drilling out a broken bolt can be very difficult in aluminum. A screw extractor is a very hard piece of metal designed to break off and foil further removal attempts.

 

[andy6374]

Re: Poppit valve on an early 90s Merc 115

grandall-<br />Normally this would be the correct course of action, but not here unfortunately.<br /><br />The bolts are right near where the mid-section meets the powerhead and if you heat those bolts I guarentee you'll cook/blow the powerhead adapter gasket. Then you will end up also having to remove the powerhead mounting bolts and those like to snap as well.<br /><br />In this particular case I say if they are going to bust...let em. It's sorta of sucky situation that you are going to have to deal with. <br /><br />You know you are a saltwater backyard mechanic if you are breaking bolts.

 

[grandall]

Re: Poppit valve on an early 90s Merc 115

Andy-<br />Ouch! That's bad! If they break will it come apart so they can be drilled out?<br /><br />I spent the last 40 years boating on the Maine coast and know what you mean about saltwater. I spent a winter taking a 35hp Johnson apart and I put it back together with NeverSeize, thinking that would keep threads from seizing. First trip out the flywheel nut and a few bolts started backing out so I had to troll back and redo everything with LokTite. Once I broke off a tap while chasing out a broken screw extractor (why are they called Easy Outs?). The motor is still going with the tap holding the lower unit to the power head. <br /><br />Gary-Florida<br />'83 I6 115hp

 

[andy6374]

Re: Poppit valve on an early 90s Merc 115

Easy outs are your worst enemy, especially if the break.

 

[gss036]

Re: Poppit valve on an early 90s Merc 115

If you happen to break them off, make a center punch start hole in the center(very important) of the bolt. Start with a small drill bit, 3/16 or 1/8 inch and drill in as far in as is safe w/o hitting the block. Then progress upward with drill bits until you have very little of the bolt left. Spray and soak with P B Blaster or the likes, then using the smallest center punch you can find, tap the side of the threads toward the center and they should come loose and leave the threads in the block. It is a slow process and takes patience, take your time and it will work for you.