Questions about replacing gaskets and seals

[Chris1956]

Heat the water jacket cover bolts and spray with penetrating oil. Let the bolt cool and suck in the oil. Repeat...now use a hand impact driver to try to coax the bolts out. After you break 1/2 the bolts on the cover, you get to face the inner water jacket cover bolts. These are epoxy'd in place and are even harder to remove without breaking.

Best of luck....

 

[Bill kubiak]

I was using PB Blaster penetrating oil for days on mine before I gave up and decided to drill em out, I just cut off the third bolt and center punched it, My punch is one of those spring loaded deals. Now I gotta go out and do the drilling. My manual in all the assembly pictures and instructions says to use Loctite Grade A and in many it shows a little picture of a tube of Loctite
I did the vise grip thing all to no avail, even resorted to a miniature pipe wench I have. watching for your email
I have no idea how to draw arrows or write on a picture in my Mac desktop, anyone that can tell me how would help a long way in pointing to the holes and things in the pictures I am talking about

 

[mlbinseattle]

Heat the water jacket cover bolts and spray with penetrating oil. Let the bolt cool and suck in the oil. Repeat...now use a hand impact driver to try to coax the bolts out. After you break 1/2 the bolts on the cover, you get to face the inner water jacket cover bolts. These are epoxy'd in place and are even harder to remove without breaking.

Best of luck....

And there are 16 of these inner jacket bolts. Yay me.

Is there a better way than removing the inner cover? Pray tell.

 

[mlbinseattle]

I was using PB Blaster penetrating oil for days on mine before I gave up and decided to drill em out, I just cut off the third bolt and center punched it, My punch is one of those spring loaded deals. Now I gotta go out and do the drilling. My manual in all the assembly pictures and instructions says to use Loctite Grade A and in many it shows a little picture of a tube of Loctite
I did the vise grip thing all to no avail, even resorted to a miniature pipe wench I have. watching for your email
I have no idea how to draw arrows or write on a picture in my Mac desktop, anyone that can tell me how would help a long way in pointing to the holes and things in the pictures I am talking about

Bill, I use a PC, but I'm sure your Mac probably has a "Paint" program or something similar. You'll just need to look for it. It will enable you to draw lines, text, etc.

 

[Bill kubiak]

Finished drilling and re tapping number three broken bolt, just got the last one cut off and center punched, taking a break waiting for my wife to get home to hold the flashlight on there while I drill it out, it is the bottom hole and I barely had room to get my dremall in there to cut it off.
BTW do not cut them absolutely flush with the block, leave a little bolt sticking out around a 1/16 to 1/8th, reason once you have drilled thru, it in my case the largest drill I worked up to was 13/64th's and wiggled it around a bit in the hole to get as much of the old bolt out of the threads that I could and my tap size is 1/4-20
after drilled out and before tapping I found that smacking what was left sticking out with a chisel broke the remaining bolt a bit and made it a little easier to run the tap in and out, right now I am trying to figure out a way to put an extension on the tap to work it, I have no room at all under there.

 

[mlbinseattle]

Bill, 13/64 (#7 drill bit size) is the largest you'll want to go when tapping for a 1/4-20. I imagine that, in a perfect world, if the drill bit went straight through the center of the old bolt, then the remaining threads could be removed or cut through when tapping. However, it's not a perfect world, and I imagine that the hole won't be exactly centered and some of the remaining threads will be left and tapped into when tapping.

I seriously don't see how you're going to get those bottom bolts without removing the powerhead. I looked at mine, again, and I can't get that cradle down far enough to even get a ratchet and socket on the bolt heads. In addition, when it comes time to re-install, those bolts will need to be torqued with a torque wrench. My eye-lift arrives, tomorrow, and what I intend to do is to remove the lower drive section (I need to do that, anyway, to change the impeller). Then, I'm going to unbolt the powerhead at the bottom (everything else is disconnected), lift the powerhead, remove the cradle, then set the powerhead back on the base and run a couple of nuts on the studs to hold it in place while I work on it.

Thanks for the tip about not cutting the old bolts flush with the block. I'll keep that in mind when I do mine.

 

[Bill kubiak]

Bleev Dis or not but I actually drilled out and re tapped that broken bottom bolt, That bottom part of the cowling is/was in the way but with all the various bolts out of it it was just loose enough and we pulled it up just enough to get the drill in there and I used a 6 inch long 1/4 socket extension with a 7/32 socket on that fit the end of the tap perfectly and used my ratchet in baby steps and got er done. Yes 13/64 was the final drill size I used and I found it a tad easier to tap it then. During
re-assembly I plan to use Loctite grade A and a thin coat of clear RTV which I just happen to have a tube of on both sides of all gaskets, I want nothing to leak or work itself loose.
Now if can just remember how it goes back together.

 

[mlbinseattle]

Congrats on accomplishing that without removing the powerhead. You da man! Now that you've accomplished that, are you going to take that inner water jacket cover off? I'm debating whether to do mine or not. If it's not leaking water into the cylinders, and I don't believe it is, I don't see any reason to take that inner jacket cover off.

Also, did you have any difficulty getting the exhaust cover bolts removed?

 

[Bill kubiak]

Don't have an inner water jacket cover, when I removed the exhaust cover it had another panel behind it that I did remove just to have a look in there, exhaust cover bolts came out easy.
Gonna start another post about water pumps, I was wondering what happens if you inadvertently install the impeller and bend the vanes in the wrong direction, will they fix then self or self destruct???

 

[mlbinseattle]

Bill, after reading about your success, I was determined to get the water jacket cover off before needing to pull the powerhead. I managed to get two of the bottom bolts out without breaking those off. The third bottom bolt wasn't so fortunate. In all, eight out of twelve will need to be drilled and tapped. Didn't think I was ever going to get that water jacket cover off. I heated those broken bolt studs a lot and resorted to some gentle prying. (I was very gentle with it. Didn't want any part of that cover breaking off on me.) Finally, I broke out the Dremmel tool and put the small diameter engraving bit on it. I used that to clean the area around the holes and broken studs. I'd swear those bolts were installed using loctite. It wasn't until I used that Dremmel tool to clean out a sufficient quantity of Loctite around the broken bolts that the cover actually began to come off. I got the cover off, and lo and behold, there wasn't any inner water jacket cover. It was like what you described with yours. The cylinders look "bell" shaped with the water jacket area around the cylinders. There are two holes on the port side going into the exhaust area, and it appears that there are two holes, one top and one bottom, one the front port side of the engine next to the cylinder walls. Couldn't see those all that well as it was beginning to get dark out here. I'll compare what I have to the what you have as soon as I see the pics of yours.

I'll get started on the drilling/tapping, today. The lifting eye/gaskets/pump kit are also supposed to arrive, today. I'll definitely need to pull that powerhead to remove that bottom cowl so I can drill/tap those bottom bolts. There is no way on mine to get a drill or a tap in there for those.

I was kind of half-way hoping that there would be an inner jacket to remove so I could get a really good look at the inside of those cylinders. However, after thinking about it, I'm glad there isn't one to remove. It would have been an even more pain to deal with. I'm going to buy one of those small work lights, the ones that are one a flexible tube of sorts with the light on the end. I'll stick that inside the spark plug holes and shine it up against the walls to see what it looks like in there.

I'll probably use grade A Loctite on mine, as well. That's the red stuff. I've used that before on 3/4" studs, and I struggled to break those loose and unscrew when the time came. No wonder those 1/4-20's just snapped off so easy. I personally think Mercury didn't intend for those bolts to ever be removed. I suppose since the design called for small bolts around sufficient heat and vibration, they didn't want to take any chances.

With respect to your impeller being put in with the vanes backwards: I'd fix that before running it. From what I understand, that's some pretty tough material, and once it forms, it might break once formed into shape with the vanes moving in the wrong direction. Just my opinion. I don't have any experience with those, so I couldn't say yay or nay for sure. Hope you find the answer to that question. Edited: I saw the thread you started about the impeller and the response you got. I was surprised that the impeller should be able to "fix" itself provided it hasn't sat there for years. Oh well, I haven't actually laid eyes or touched an impeller, yet, so I guess those are pretty flexible. Live and learn.

 

[Bill kubiak]

Send me a regular email and I can send the pictures, I sent you the address on a PM

I plan to use permatex on both side of all the new gaskets to be double sure I have no leaks, I will never take this apart again

was pressure washing the sidewalk this morning will finish it this evening just to darn hot now

when you remove the exhaust cover you will be able to see the cylinder walls thru the exhaust ports, make sure the rings are not broken or stuck by rotating each piston up and pressing in on the rings with a small screwdriver, if good they should spring back, I kept spraying PB Blaster on mine to loosen any junk that may have built up

 

[mlbinseattle]

I already sent you a regular email, once already. lol. I'll do it again.

Did you remove the exhaust inner jacket gasket after you removed the exhaust cover? If so, was it hard getting those bolts out for the inner jacket gasket?

I already checked my rings when I removed the transfer port covers. I used my finger and the blunt end of a pencil without eraser to push on the ring to check for spring/tension. Those are good.

By the way, I managed to work out three of the broken bolt studs, this morning. Did it with heat and a pair of channel locks. This leaves five that I'll need to drill/tap on the head cover/water jacket cover (whatever it's called). Also, there are three holes, not two, on the port side of the water jacket with more holes in the back that appear to be going into the exhaust area. I was able to see better now that it's daylight, here.

 

[mlbinseattle]

Managed to work another broken one out with a pair of channel locks. That leaves only four that will need to be drilled and tapped. :joyous:

Oh yeh ... on mine, it appears that there is an exhaust inner plate that's in-between the block gasket and the outer plate gasket. I'm thinking that there isn't an inner jacket gasket like I've seen on other engines. If I'm correct, it appears that plate is held into place using the same bolts as the outer exhaust cover. Is that the case with yours?

 

[Bill kubiak]

On mine that is called a Divider Plate, Did not work on the motor today, I continued with the pressure washing, almost done and I am beat, did you see the pics I sent

Oh wait, I did test fit the Cylinder block cover to be sure I could thread all the bolts in, I had two that were not perfectly drilled dead center, they were just a little off, everything fit, I will assemble it tomorrow

 

[mlbinseattle]

Yes, I saw the pics. Yours is designed the same as mine. After I got that water jacket cover off, I immediately understood why the pistons/rods had to be attached to the crank and the entire assembly installed into the block from the front end. I'm so used to dealing with car engines that have heads. It was educational to see an engine like this opened up.

Your engine looked pretty clean ... inside the water jacket area around the cylinders. Did you clean that, or has yours never been in salt water? I'm beginning to think mine has and wasn't rinsed regularly.

 

[Bill kubiak]

AS far as I know it has been in salt water all it's life, I was just as surprised when I opened it up and saw how clean it was
BTW as far as I know only mercury/mariner are built the way they are, most others have a cylinder head that can be removed like Johnson and Evinrudes, I had a 5 hp Western Auto Wizzer when I was a kid but do not remember much about that one

At the very beginning of this thread you said you had compression on 4 cylinders and a few replies down #3 Chris mentioned something about spark plug #6, just what do you have???

 

[mlbinseattle]

It's a '76 850 4 cylinder. I believe there was a 6 cylinder version, IIRC, so that may have been what Chris was thinking.

 

[Bill kubiak]

How did you make out with the drilling and tapping????

 

[mlbinseattle]

I got started a little late with the actual drilling. Got one drilled and tapped. Got the second one drilled. Got dark, so I packed it in for the day. I probably would have gotten the second one tapped had the t-handle not give me fits while tapping the first one. I couldn't get it to tighten enough around the tap, so it kept slipping. Finally got that to work. Tomorrow, I have to take care of something, first, then the rest of the day will be on the engine. Parts and the eye-lift arrived, today, so the plan is to finish tapping the second one, drill and tap the third one. Lift the powerhead high enough to remove the lower cowling and then set it back down ... secure the powerhead with a couple of nuts on the studs. Drill and tap the fourth and last one. Pull the exhaust cover and divider plate. Take a look inside that area and hope the water jacket cover gasket looks okay. I'm sure mine has that after looking at the exploded view, again. I was told that the water jacket cover (inside the exhaust area) is just as bad as the cylinder block cover with respect to the bolts snapping. I really don't want to deal with that cover unless I absolutely need to.

If I don't need to deal with the water jacket cover inside the exhaust area, then I'll take the powerhead back off, replace the bottom seal, and then re-install all the covers and everything else. I still need to install the water pump kit on the lower unit. I'm probably looking at a few more days of working on this thing. I'm hoping to have it back on the water by Saturday, maybe earlier.

I was reading another post where the guy had to remove his exhaust cover, and several people advised him not to pull that water jacket cover unless absolutely necessary. They suggested that RTV (black or red) be used in any water leak area because of the water jacket cover gasket. I think I'm going to do this if necessary. Beats having to deal with more snapped bolts just to change a gasket.

 

[Bill kubiak]

In another post I mentioned that my wife discovered that a bolt was missing from the fwd left hand side of the powerhead to mid leg. Turns out it was not a bolt, it was a stud and a nut and washer screwed onto it. There is insufficient room to get a new stud in there and there is also insufficient room to thread an appropriately sized bolt to get in there and just get a few threads started. I hate to pull that powerhead, there is just so much stuff to remove to do it. My neighbor suggested I take the SS bolt that is about a 1/4 inch too long to work in and grind it down and see if I can get a couple turns on it and then use thread locker and RTV to seal it in place. Waddyathink Gang???????