1975 500E - Water in bottom two cylinders

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Posted some pics of the open exhaust port. Arrows show where there are holes/tears in the gasket. Everyone agree that it looks like this is where water was getting in?<br /><br /><br />

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[emckelvy]

Re: 1975 500E - Water in bottom two cylinders

Sure looks Icky! Did a good job of washing the carbon off didn't it???<br /><br />Be sure to check the exhaust baffle plate for pinholes and thin areas to rule out any problems there.<br /><br />A good way to clean all that old nasty hardened-on gasket material is with a wide razor-bladed-type of scraper. Wal-Mart sells one with a nice handle and replaceable wide blade. You can scrape those surfaces nice and clean with something like that.<br /><br />A careful application of gasket remover will also help but be careful where it goes as it'll eat painted surfaces, etc. as well as gaskets.<br /><br />For sealing up the inner plate I like to use an anaerobic-type of sealer such as OMC Gel-Seal or Loctite (now Permatex brand I guess) sealer. The advantage over RTV is that it only hardens where it is squeezed. So any of it that 'squishes' out into critical water passages will just wash away, whereas RTV will not and may plug something up. If you do use RTV, use a Very Very thin coating of it.<br /><br />For the outer exhaust cover I like to use Permatex or equivalent #3 Aviation-type sealer. Brushes on nicely and never hardens. Put a light coating of #3 or anti-sieze on the manifold bolts when you reassemble and they'll never get frozen in the block.<br /><br />Anyway, looks like you're on the right track, you might also consider pulling the lower bearing cap while she's down. Not that much more work now that the powerhead's off.<br /><br />Have Fun, you're now a bona-fide Merc Mechanic!......ed

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Thanx Ed. Yep the Baffle Plate has a lot of pitting and looks like a couple of pinholes so went ahead and ordered a new one. Will pull the lower bearing cap today for a looksee. Sure do appreciate the advice on the sealants. Good info and I will follow it. Think I will wait til I get it reassembled and out on the water before I accept the bona-fide label

 

[Clams Canino]

Re: 1975 500E - Water in bottom two cylinders

While it's off, you REALLY wanna replace the seals in the bottom end-cap. We don't all agree that the gasket had to have caused this. There is a puller for that end cap, if need be have the dealer do that part.<br /><br />To me it looks like owner replaced the water jacket gasket by the plugs. It appears those exhaust plate gaskets were factory install.<br /><br />And I'd bet the water intrusion is from the bottom. You'll note that those two pinholes you're pointing to are right next to a factory water passage hole big enough to drive a goldfish through, so what makes your two holes so significant?<br /><br />-W

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Certainly appreciate your opinion CC. The picture doesn't show it but you could follow the scale left by water thru the gasket and baffle plate into the exhaust chamber. As mentioned there is also a lot of pitting and what appears to be pinholes in the baffle plate itself. But having gone this far, I have no intention of being pennywise/poundfoolish and will attend to the seals. Thank you for your input.<br /><br />Manual shows a bearing in the lower seal housing. Is it a factor in replacing the seals or will I be able to pull the old seals out and replace without messing up the bearing?

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Ok got the lower seal housing off. Harmonic balancer pulled it out like it was butter. Didnt even need a wrench, just turned it out by hand. Dont see any sign of anything going bad inside there, but since Im this far want to go ahead a replace the seals. Any guidance on how to pop that bearing out so I can get to the seals? Manual is a little vague on this one, just basically says "remove bearing".

 

[emckelvy]

Re: 1975 500E - Water in bottom two cylinders

Ok, so you've got the type where the bearing presses into the cap.<br /><br />Best way to do it without 'special tools' is to bore a hole in a 2X6 or suitable other piece of wood, such that you can place the bearing cap in the bore. This'll support the cap properly while you drive the bearing out.<br /><br />With the cap oriented such that the bearing is facing downwards, use a suitable drift or other tool and drive the bearing out from the other end.<br /><br />Drive it out against the inner race. You'll have to make sure it comes out evenly as it's a fairly tight press fit.<br /><br />After the bearing comes out, note the position and orientation of the (2) seals and then drive them out too. Clean up the cap, and drive new seals in. I like to put a thin coating of Permatex #3 on the O.D. of the bottom seal; also you can put a bit of waterproof grease on the seal's lips and a bit in between the (2) seals.<br /><br />You can get a new bearing inexpensively at your local auto parts store or bearing specialty house. Just ask for a 'straight 206' or "6206 unshielded" ball bearing and they'll know what you mean. Lots cheaper than the Merc dealer.<br /><br />The Sierra Marine P/N for the crank seals is 18-2016 (Merc P/N 26-41953) and www.boatfix.com probably has the best price on the Sierra seals.<br /><br />When you go to press in the new bearing, if you have a press it's a Good Thing. You can also freeze the bearing for an hour or so to shrink it, and it'll go in easier (although you'll still need to press or drive it in). Don't press or drive via the inner race as you'll damage the bearing. Any force applied should only be to the outer race. If you drive it in, use a suitably-sized pipe or other equiv tool that'll clear the inner bore of the bearing cap, but will bear sufficiently on the outer race of the bearing.<br /><br />Install a new O-ring on the bearing cap. Smear a coating of waterproof grease on the O-ring and on the bearing cap surfaces where it'll contact the block.<br /><br />Gently guide the cap back in place and tap evenly until bolts in the cap's mounting 'ears' will engage the block. Pull down the cap evenly or the 'ears' will break off. Torque to 150 in-lbs.<br /><br />BTW if you apply a coating of Permatex or grease to the bearing cap bolts, they won't ever sieze in the block. Not such an issue in fresh water, but believe you me out here in the PNW you really appreciate it if someone's worked on it previous and put something on the bolts. Or conversely you're ready to cuss them out if they didn't!!! <br /><br />HTH & Happy Wrenching.........ed

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Success. Got the bearing and seals out. Went to Advance Auto Parts and they had a pivot bearing puller as part of their loaner tool program. Was a tad tricky getting the fingers to grab the inner race. Pretty tight fit with the seals in there, but after a couple of tries It pulled it right out. Now just have to wait for all the parts to get in and its reassemble time!!! Thanx for everyones help and a special thanx to Ed for your detailed guidance. Barring any problems in putting it back together, I will report back when done.

 

[Clams Canino]

Re: 1975 500E - Water in bottom two cylinders

When yo uput the new seals in , fill the void between them with a good grease.<br /><br />And if the baffle plate has holes in it... then it's bad.<br /><br />-W

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Will do with the grease and agreed on the baffle plate. New one on order and should be here Tuesday. Thanx for the help CC.

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Going to start putting everything back together this weekend. Have searched all the local auto parts and marine stores and cannot find Permatex #3. They all have Permatex #2. Will this be an ok substitute?<br /><br />"Permatex® Form-A-Gasket® No. 2 Sealant<br />Reliable paste-like gasket sealant/dressing/coating. Form-A-Gasket #2 sets more slowly to a pliable film best suited for non-rigid, vibrating assemblies. Use to 400°F (204°C). Resistant to gasoline and other solvents. Conforms to MIL-S-45180 D. <br />Suggested Applications:<br />Coating cut gaskets to improve sealing and hold in place.

 

[emckelvy]

Re: 1975 500E - Water in bottom two cylinders

I never did care for #2 because even though it says 'non-hardening', it gets hard as a rock with age and heat. Surprising they don't have #3, my local auto parts store can get just about any Permatex product.<br /><br />If you can spread the #2 out to a thin layer I don't see where it's going to hurt, if that's all you can get then it's probably better than none at all.<br /><br />Also surprising that a marine dlr didn't have Sealer 1000 or equiv. You could also use OMC Gel-Seal but it's somewhat spendy. Good stuff though.<br /><br />Have a good one, I'm working on (2) 1958 40 HP Johnrudes this weekend but may also be picking up a '70's 850-4 Merc. That's more like it!........ed

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Thanx again Ed...got the crank housing all put back together with no problem. Went out this morning and hit one last auto parts store. It is a little old rundown independent operation and lo and behold he had one can of #3!!! <br /><br />Have fun with those old '58's and hope you score the 850. Will post back as I progress.

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Well against my better judgement I got her all reassembled, still same symptoms. Im afraid I botched the crank seal replacement by driving them in too far. You guys spoke of a void between the 2 seals, I really didnt have one. In fact there was probably about a 1/16th inch gap between the bearing seat and the inside seal. If I drove them in too far would it cause it to still leak? Only other thing I didnt do was replace the gasket between powerhead and exhaust extension plate. Anyway for that to cause a problem? Thanx for your help.

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Shameless bump ^

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Ok, ordered new seals and will try again. Sure would appreciate any advice and detail so I can get it right this time. Also am replacing both gaskets between powerhead/extension plate and plate/midsection. Do these gaskets need any sealants?

 

[emckelvy]

Re: 1975 500E - Water in bottom two cylinders

R, the seals shouldn't leak even if they are a bit far into the housing; as long as the surface of the crank is OK where they are contacting, should be OK.<br /><br />I guess it's possible the exhaust adapter plate could be spraying water up into the exhaust passages; when you have the adapter plate out, also check the water tube for pinholes/cracks. Check the water tube's rubber sealing grommet and replace if it looks bad.<br /><br />You can use some sealer on the gaskets but if you end up with the new blue-color gaskets, they are made of 'sandwiched' material and don't really need anything on them. Won't hurt if you do, though.<br /><br />On the crank seals, usually you can drive the first one all the way down until it stops in the bottom of the machined cavity. Then drive the upper seal down below the plane of the ball bearing, but not hitting the lower seal. Make sure of course that the lips on both seals point downwards or it'll suck water in. <br /><br />You'll probably also notice some small holes in the bearing cap, going from the I.D. to the O.D. These are the bleed holes to recirculate excess fuel/oil to the upper end of the motor. Be sure you don't block these holes with either seal.<br /><br />Your bearing cap will either have a check valve embedded in the cap, or will have a check valve screwed into the lower part of the block. Make sure the 'check' function of this valve works properly by blowing from both directions; it should only blow freely one way. If the check valve isn't working you should replace it.<br /><br />G'luck............ed

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Glad to see ya back Ed!! Got a new set of parts in, thankful that my screwup wasnt overly expensive. Only had a few minutes to look at the motor this evening. Think I found the check valve. There is a vacuum-type hose leading from the top of the block to a screwed in connection at the bottom of the block. Will pull that 1st thing this weekend and check it. Just out of curiousity what does this valve do? Did a search on the forum but all it came up with is about 300 posts on poppit valves.

 

[emckelvy]

Re: 1975 500E - Water in bottom two cylinders

The check valve normally lines up with the holes in the main bearing cap, and excess mix, which goes to the lowest point, gets sucked up the bleed hose to help add a little lube to the crank's upper ball bearing.

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Ok gotchya. Found it and it appears to be faulty as I can blow in at the screw end and also suck in air at the some end. So I guess I need to replace it too, but this wouldn't have anything to do with my water in cylinder problem would it???