Blown head gasket?

[Navgunner]

I finally got my 115 Johnson started up (115ESL73M)on muffs. Rebuilt carbs and new ignition switch. She fired right up like a champ. I ran it for a few minutes on the muffs at idle and shut her down to run a compression test. Had about 126psi on #1 and #3, and 120psi on #2 117psi on #4. That seemed acceptable to me so I plugged it back up and decided to run it a bit more since it had set for a couple of years before I got her. <br /><br /> Good news is the water pump seems to be working fine...it started leaking water from the head gasket down the outside of the block (along the gasket) I was only running it at idle, and it just started after I had run the compression test (I had been watching pretty close before the test while warming it up and all seemed good). <br /> I talked to my neighbor and he said I should have lost compression if the gasket has gone. So I ran another comp test on it and they came out to be dead on same readings.<br /><br />Couple of questions:<br /> <br /> <br /><br /> Can I just pull the head off and replace the gasket? Since I witnessed it go, and I shut it down I would like to think there is litte chance it had the opportunity to overheat. If I were to replace the gasket can I do so without fooling with the gasket to the head cover? (just pull the head, replace the gasket and let her rip?) My brother in law says the thing to do would probably have the head milled down ( I am hoping this is not the case) I bought this motor in hopes of salvaging the rest of the season while my Rude 135 is currently seized up. <br /><br /> Any thoughts would be appreciated!

 

[jfm1]

Re: Blown head gasket?

what I would do is get a peace of glass, lay it on a flat surface place a sheet of sand paper on it, take your head and with even pressure run the head over the sand paper, that will clean up the surface and you should beable to tell if the head is warped. I am by no means an expert, but I have done this and it worked Good Luck

 

[Goodoleboy]

Re: Blown head gasket?

Hi Gunner!<br /><br />If it were my mtor and I was getting compresion readings that high, I wouldnt suspect a blown head gasket.<br /><br />Id look real hard for sorce of water leak. Such as hose going to telltale mabey, likley not that simple . <br />Good luck.

 

[Navgunner]

Re: Blown head gasket?

Here is a pic of where I am finding the leak from. It seems the leak is coming from the top and running down both sides of the head gasket. What kind of options do I have here?

 

[Goodoleboy]

Re: Blown head gasket?

I could be as wrong as two left feet. But I dont see how on earth you could get good compression reading on a blown head gasket.<br /><br />If that top cylinder were reading 40 to 50 pounds I would beleive it.<br /><br />It just mite be possible you have a cracked block just behind the head. Ive never heard of an outboard freezing and bursting. They are suposed to drain all water when loaded on the trailer.<br /><br />But then on the other hand theirs one heck of a lot of things Ive never heard of.

 

[ddbyrd3]

Re: Blown head gasket?

Those are real good compression numbers... Yes you can pull the head and change the gasket WITHOUT removing the head cover. <br /><br />I read in a post where it was suggested that you just need to clean the mating surface and you dont need to use the glass trick, not on these heads.... Just make sure the gasket sufaces are cleaned up real good.<br /><br />One thing you will definatly want to do thought since you will have the head off is replace the deflectors... They are rubber hose looking deals in the block.. you cant miss them... Pay particular attention where they are located and simply replace.<br /><br />I just did my head gaskets on my 140... I think it took all of an hour and a half to do both sides..

 

[jleus]

Re: Blown head gasket?

The head gasket not only seals the sleeve and cylinder of the block casting to the top of the cumbustion chamber in the head but also seals the water passages as they form the galleries that come up the sides of the block and into the water jacket on the head. You could easily have a leak on the outer portions of the head gasket (leak cooling water to the exterior) and still have a seal on the crush ring portion of the inner part of the head gasket. BUT I would bet that a head bolt (or bolts) have loosened and that a loss of cylinder seal would not be far behind. Short of breaking a fastner during disassembly both head gaskets and head cover gaskets are short work. If you leave it as is I would almost garuntee a completely blown head gasket.

 

[Navgunner]

Re: Blown head gasket?

So do you mean to say I need to pull the head covers and replace those gaskets as well?<br /><br /> And thanks to all for your inputs here!

 

[ddbyrd3]

Re: Blown head gasket?

You dont have too, but I think jleus is saying if one is going, the rest are not far behind.. You might as well do them all, head covers, and BOTH head gaskets.... 2 hours worth of work for priceless peice of mind..... Not a bad trade off.

 

[Goodoleboy]

Re: Blown head gasket?

I would try retorqueing the heads and see if the water leak stops. I dont know what the torque specs are for your motor. but should use a manual, Mabey somebody will tell you shortly.

 

[Goodoleboy]

Re: Blown head gasket?

Byrd is rite in saying peice of mind is worth alot. Head gaskets dont cost much and a couple hours of your time now, mite save you a headache from worrying.<br /><br />But its your motor do as you please.

 

[Navgunner]

Re: Blown head gasket?

Goodoleboy,<br /><br /> I was thinking of trying that, but I would rather spend a couple of bucks on a gasket now, even if it isn't bad, than have an overheat and warp the heads. That's my logic anyway, if I am way off just say so. <br /><br /> Thanks for the input all the same!<br /><br /> I am calling around looking for the gaskets, hopefully be able to get her up and going for next weeks vacation.<br /><br /> If anybody else has any thoughts please feel free to chime in. If not I will post afterwards and let you all know how it works.

 

[Goodoleboy]

Re: Blown head gasket?

Your rite on with your logic. If a new set of gaskets made me feel on little bit better, Id do exactly the same as you.

 

[ddbyrd3]

Re: Blown head gasket?

I dont know if this will apply to your application but it did to mine..... They offer standard head gaskets, and "low compression" head gaskets.. You may be able to read the part number off the gasket you remove just make you you get the proper type, STD or LC...... I would recommend standard....