1975 500E - Water in bottom two cylinders

[emckelvy]

Re: 1975 500E - Water in bottom two cylinders

Shouldn't but might as well fix it while you're at it!

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Hehe ok I'm anal enough to agree with that. I just hope my parts guy doesn't think I'm coming on to him. Seeing more of him lately than my wife!!

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Well I'm stumped. Put in another set of seals, and I'm confident I got it right this time. New exhaust gaskets. Replaced the check valve. Still no go. Where in the h*ll is this water getting in? Only other thing I can come up with is to double check compression but after having the powerhead apart 3 times now it sure looks clean and solid. Rings are clean and tight, pistons shiny, Im just lost at this point. Any ideas guys??? Thanx for your continued support.

 

[rodbolt]

Re: 1975 500E - Water in bottom two cylinders

does your engine use an inner exhaust plate like the larger 4cyl motors of the time? and occasionally the jug would corrode a hole in it. to find a holed jug will require air pressure a careful ear and a way to inject air into the cyl while holding the crankcase. look at your manuals exploded block diagram and see if it has a block mounted exhaust diverter and a exhaust plate.

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Hey thanx for the input RB! Not sure what you are referring to here. Went thru all the parts diagrams and dont see anything referencing a jug or diverter. It does have an exhaust baffle plate between the outer exhaust housing and the block. I did replace that one. Appreciate all the help.

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Ok finally got ahold of a compression gauge so Im gonna check it tomorrow. Manual says to "disconnect ignition system to render it inoperative". Hmm ok, seems like they could perhaps tell me how? At the risk of sounding stupid, could one of you pros provide me with some instruction here? Thanx in advance.

 

[emckelvy]

Re: 1975 500E - Water in bottom two cylinders

You can leave the key off, and jump across the +12V battery cable at the solenoid, to the yellow wire which connects to one of the small terminals on the starter solenoid. This'll crank the motor over for your compression test without sparking. <br /><br />Or, pull out the plugs, stick them back in the plug wire boots, and ground them against the block. This'll allow the system to spark when you turn the key without any risk of harming the system by sparking unloaded. Not likely to hurt things even if you did that, but no sense pushing your luck!<br /><br />BTW, one time I had a pesky Inline with a leak and I made a plate out of solid alum sheet to bolt to the bottom of the powerhead and block off all the water passages. Use the powerhead gasket as a template to drill the plate. Use a solid piece of gasket material on the test plate. You can pressurize thru the "pee hole" fitting to a max of approx 12 psi. If you have a pourous block, leakage from a cracked 'jug' or a warped sealing surface, this should find it.<br /><br />My only other thoughts on the problem would be to inspect the exhaust area after running, to see if you have milky deposits which would indicate leakage at that point. Of course you'd have to pull the manifold in place (if you can get at all the bolts), or pull the powerhead (which is probably a given at this point).<br /><br />The 500 doesn't have any inner exhaust port cover to leak, as the larger inlines do. So, if it's leaking from the exhaust side you've got a crack, a warped exhaust plate (even a new one could be defective!), or leaking block surface. The block could be machined straight, other problems of course might be harder to deal with.<br /><br />I've never had any big water intrusion issues with 500's except for leaky bottom seals or holed exhaust inner baffle plate, so your motor is certainly one for the textbooks!<br /><br />Here's hoping you're close to getting to the bottom of the problem, G'luck........ed

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Yesss!! Just the kind of info I needed. Been wracking my brain trying to think of a diagnostic to find the leak. Was stuck inside the box and trying to figure out a way to shoot some kind of dye up thru the water pump. You went outside the box and shooting water thru the pee hole makes all the sense in the world. Thanx immensely and I will let you know what I find.

 

[emckelvy]

Re: 1975 500E - Water in bottom two cylinders

I was thinking of air but water might do just as well. You may find a smaller leak using air but seeing as how your motor is ingesting plenty of water, if there's a problem with block integrity it should show up!<br /><br />BTW, that old 1150 block I had trouble with sucking water into #3 cyl had a cracked cylinder, the integrally cast 'jug' had been damaged by a broken reed valve. Most reed valves just get spit out the exhaust if they break, but on this motor a chunk 'speared' the top of the cyl and made a very small crack. So much for that block, and it's still sitting in my garage with all the nicely machined sealing surfaces!<br /><br />G'luck with yours...........ed

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Ok, compression checks out good. 120 psi all the way around. Pulled the powerhead again (boy im getting good at this part ). I am going to include a picture of the inner gasket at the top of #4 cyl. <br /><br />

<br /><br />There is milky deposits visible so looks like I still havent gotten the gasket seated right. Ed, you mention a warped exhaust plate or leaking block surface which makes me think of something I did that might have created more problems. When I first took off the exhaust cover and was cleaning up the old gaskets, the cover was a little rough in spots, so I took a dremel with a sanding disk and cleaned it up nice and shiny. Is it possible that I ruined the sealing surface by doing this? Thanks so much for all your help, I still think this thing is doable!<br />Well, went ahead and pulled the exhaust cover and sure enough, more creamy deposits between gasket and baffle plate right around the water inlet above #4. I did this set without any sealant, and that obviously didnt work. Got another set ordered so will try again. Any advice in the meantime is most appreciated.

 

[emckelvy]

Re: 1975 500E - Water in bottom two cylinders

Well, she's definitely blowing chunks on the exhaust side!<br /><br />Regarding the exhaust cover, it's never a good idea to clean gasket surfaces off alum parts with any kind of motorized device. Tends to start removing metal along with the gasket. Gasket remover and an purpose-built gasket scraper (or what I like to use, a broad T-handled razor-blade scraper, cheap at Wal-Mart) work very well. Some of the gasket material 'welds' itself into the metal and you just have to very carefully scrape it smooth.<br /><br />If you can find a good straightedge, you might check the surface of the block for low spots. Seems your water is blowing out from between the new baffle plate, new gaskets, and block surface so that's the area you need to concentrate on. <br /><br />If the outer cover isn't leaking externally I wouldn't worry about it so much. It would have to be pretty bad before it would transfer problems to the other side of the 'sandwich'. You could get a thick piece of glass, lay some coarse 'wet & dry' sandpaper on it and do a home-made 'surfacing' job on the plate to flatten it up.<br /><br />So, either the new exhaust plate has issues, or the block itself. A machinist could very carefully mill the plate and/or block flat. Note that any material removed off the block or sealing surfaces of the baffle plate will place the baffle plate closer to the exhaust ports. You'll have to be sure the plate doesn't bottom out against the block; if it does you'll need to remove an equivalent amount from the edges of the baffles on the plate.<br /><br />You can machine the block without having to tear it all apart, if you strip the accessories off it and seal up all holes tightly. Clean off the exhaust ports, and seal them up with silicone seal, tape, etc. Something that'll easily peel off afterwards.<br /><br />P.S. I'd clean out the entire exhaust area with solvent and check the block for any cracks that might cause leaks.<br /><br />Looks like you're at least closer to the problem now! Let us know what you find.........ed

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Found me a nice thick piece of glass (hopefully "she that always says no" wont notice the oil marks on her wine vault shelf). Made a little feeler gauge out of paper and yep, there was a little burr right where she is barfing water. A couple of swipes with sandpaper and it now feels smooth as a baby's bootie. So time for another go at it.<br /><br />I'm thinking that with the history of trying to get this exhaust gasket to seal I should use sealant on this go. Ed, in one of your previous posts (and man I sure appreciate you hangin with me on this) you stated to use either an anerobic type sealant or OMC gel-seal. I have found a permatex anerobic sealant. It is blue and the instructions call for a "surface activator" to be sprayed on the two metal surfaces and allow it to set for a couple of minutes, then apply the sealant to both sides of the gasket. Are you familiar with this one and do you think it is suitable? I did a search on OMC gel-seal and came up with a couple of different numbers. If this is the better product at this point I dont mind spendin a little more $$ to get it right. I am assuming it would only be availalbe either online or at a JohnyRude dealer. Just want to make sure I get the best one for this application.<br /><br />Thanx for your help.

 

[emckelvy]

Re: 1975 500E - Water in bottom two cylinders

Mercury used to supply a kit made by Loctite that was called Master Gasket and that's what was used to seal up the crankcase gasket joint on Inlines, etc. I used that for many years and it cured very nicely, sealed that joint great. It was 2-part with spray activator and the gasket gel. There was another Loctite product that I used that was just one part and didn't cure until the pieces were squished together.<br /><br />As long as whatever you're using is a true anaerobic sealer and the excess that squeezes out into water passages when the joint is tigthened, won't cure (and thus will get washed away), it should work fine. The biggest concern would be having cured sealer lay in the water passages where it might plug something up. The exact reason I don't like to use RTV for critical sealing surfaces like exhaust manifolds. In a pinch you could use it but only in extremely thin coatings.<br /><br />I couldn't tell you whether or not the OMC Gel Seal is better but I've always had good luck with Loctite/Permatex products.<br /><br />This stuff looks very similar to the Loctite product I've been using for years and from what I understand, Permatex bought out or took over Loctite:<br /><br /> http://www.midwayautosupply.com/detailedproductdescription.asp?10107 <br /><br />This stuff sounds like maybe what you found, not sure how it differs from the '515' stuff but it's more expensive that's for sure!<br /><br /> http://www.midwayautosupply.com/detailedproductdescription.asp?9401 <br /><br />I've used the Loctite version of Permatex 515 on crank flanges and manifolds alike and it seems to do the job.<br /><br />At any rate, whichever one strikes your fancy I guess as they all seem like they should work in this application.<br /><br />Maybe that 'lump' you found was enough to make it leak. <br /><br />And G'luck with the wife, hopefully the glass shelf is back to its former purpose after having served a higher one with the Merc!.......ed

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Well I finally got the exhaust gasket to seal. Turns out the problem was the new baffle plate. The lower baffle was a tad too long and would not allow the gasket to seat. A few strokes with the sandpaper took care of that. Before putting the powerhead back on I gave it one last cleaning and noticed a couple of small holes in the area of the bottom cylinder. There is one at the top and one at the bottom. This is the cavity right below the peehole. Are these holes supposed to be here or is this yet another problem to deal with? (see pics)<br />Thanx for your help and Feliz Navidad to all!!<br /><br />

<br />

 

[emckelvy]

Re: 1975 500E - Water in bottom two cylinders

Ralphy, if I recall those are cooling passages that lead into the main cooling chamber (where water circulates around the cylinders). <br /><br />Just clean them out with a wire or other suitable cleaning implement, back to the original size. This'll ensure the water goes where it's supposed to!<br /><br />Glad to see you finally found your problem, that was certainly one for the books!<br /><br />Cheers.........ed

 

[Ralphy]

Re: 1975 500E - Water in bottom two cylinders

Thanx Ed, Thats pretty much what I thought but just wanted an expert opinion rather than my best guess.