Is there a test WHAT DO I DO NOW

[dozerII]

Is there a way to pressure test, to tell if the exhuast baffle/plate is leaking into the engine. I changed one on a Yamaha 85, but it was right at the back on the motor wide open. On my 75 Merc it looks to be hidden on the left hand side under numerous other items. Any ideas would be welcome.
Thanks Glen

 

[crem1]

Re: Is there a test

Re: Is there a test

Lack of responses implies that one may have to do it the hard way, partial dismantling and putting in new gaskets

 

[Texasmark]

Re: Is there a test

Re: Is there a test

Not that I know of. What is your problem? I have a fairly recent model 3 cyl 90 which could be the same engine as yours and pulling the cover doesn't seem to be that big of a deal.

Mark

 

[dozerII]

Re: Is there a test

Re: Is there a test

Thanks for the repys. I posted some photos of my spark plugs and compression numbers in an earlier post and a couple of replys suggested the errosion of the ceramic on the plugs was caused by water leaking through the baffle plate
Glen

 

[Texasmark]

Re: Is there a test

Re: Is there a test

I'd like to help but I am not following you. The exhaust baffle to me is on the port side of the engine block, rectangular and goes from the bottom to the top of the block. Only thing in it is a rt angle hose barb that provides "pee" water. The plugs are screwed into the block at the rear of the engine and are surrounded by a water jacket cover/gasket.

Where is the thread where you showed pictures?

Mark

 

[dozerII]

Re: Is there a test

Re: Is there a test

Thanks for the help Mark. Here is the link to the origional thread.
http://forums.iboats.com/showthread.php?t=366103 I also have the pics here. The cyl with slightly lower compression is #2 and is the second plug from the left in both photos.
Thanks Glen

 

[Texasmark]

Re: Is there a test

Re: Is there a test

I'm still confused. The plugs have nothing to do with the location or access to the exhaust water jacket. Also your Avatar seems to depict a recent model 3 cyl 75 whereas the older designs had 4 plugs (which you show) and what I said is not necessarily accurate for them.

It is possible to have a hole in the cylinder wall that allows water into the combustion chamber (BTDT); it doesn't necessarily have to come from the exhaust jacket cover.

Also, the water could explain the reduction in compression on #2 as possibly that cylinder has less carbon buildup as a result of the cleansing action of the water.

And then there is also the possibility that the water reduced the lubricity of the gas/oil mix and you have excessive wear on that cylinder (cylinder walls, rings).

Mark

 

[dozerII]

Re: Is there a test

Re: Is there a test

Number 2 plug has some errosion, or pitting , of the porcelan around the eletrode, one of the posters on the last thread said it was possibly from water coming though the exhaust baffle plate. The O/B is a 84 75 hp 4 cyl and the compression is top to bottom 140, 130, 140,140. I just bought the boat and motor in November and have not had it in the water. I am currently redoing the interior of the boat and going through the motor, I just want to make sure everything is good for the spring.

Thanks for taking the time to respond Mark

Glen

 

[Texasmark]

Re: Is there a test

Re: Is there a test

Some may disagree, but 10# is not that much especially when the low one is at 130. You could get half of that in your measurement technique. Before you start worrying about tearing things apart, get a small flashlight and look all over the top of all 4 pistons (through the spark plug hole obviously). If you are leaking water into #2 the piston will be nice and clean, unlike the tops of the other 3. If they all look about the same, put your tools in your tool box, get out your fishing pole and go fishing. Grin

Mark

 

[dozerII]

Re: Is there a test

Re: Is there a test

Thanks Mark. I looked at the tops of the pistons this morning and they all look about the same. When one of the posters said #2 plug looked like water was eroding it, I got a little worried, and jumped to conclusions. The exhaust baffle plate id N/A from almost everywhere I tried, but found one on line. So I have it and the gaskets in stock if I ever need them. The motor is real full of black gooey oil and sludge in the exhaust area and in the lower part of the cowl. Is this normal, and just shows a lack of maintainace. I would imagine that running seafoam through it will help get rid of that goo.

Thanks again for the advice.
Glen

 

[j_martin]

Re: Is there a test

Re: Is there a test

Thanks Mark. I looked at the tops of the pistons this morning and they all look about the same. When one of the posters said #2 plug looked like water was eroding it, I got a little worried, and jumped to conclusions. The exhaust baffle plate id N/A from almost everywhere I tried, but found one on line. So I have it and the gaskets in stock if I ever need them. The motor is real full of black gooey oil and sludge in the exhaust area and in the lower part of the cowl. Is this normal, and just shows a lack of maintainace. I would imagine that running seafoam through it will help get rid of that goo.

Thanks again for the advice.
Glen

Maybe been idled a lot. Yes a can of SeaFoam, run through as the FAQ on the subject on this site suggests, will clean it up. It is hard on neighbors and hanging laundry, though.

hope it helps
john

 

[Texasmark]

Re: Is there a test

Re: Is there a test

As I may have mentioned on another post, I bought my current '02, 90 hp, 3 cyl, 2 cycle, Merc used and it's performance wasn't what I had anticipated.

In short, I started adding Sea Foam to the gas (did not do an official "decarb"); like I would pour in "some" and put in 5 gallons of gas, but I did it every time I went to the lake which insured I had fresh gas for the outing.

I play, fish for awhile, play, and come home. Playing is WOT, uturns and all (Grin) and fishing is electric trolling motor BB type stuff. You would not believe how clean this engine and exhaust passages are today, including the inside of the prop hub. With Merc's Top of the line oil and the Sea Foam, smoke is almost nonexistent. You have to look carefully to see any including when hole shooting.

HTH

Mark

 

[sschefer]

Re: Is there a test

Re: Is there a test

As I may have mentioned on another post, I bought my current '02, 90 hp, 3 cyl, 2 cycle, Merc used and it's performance wasn't what I had anticipated.

In short, I started adding Sea Foam to the gas (did not do an official "decarb"); like I would pour in "some" and put in 5 gallons of gas, but I did it every time I went to the lake which insured I had fresh gas for the outing.

I play, fish for awhile, play, and come home. Playing is WOT, uturns and all (Grin) and fishing is electric trolling motor BB type stuff. You would not believe how clean this engine and exhaust passages are today, including the inside of the prop hub. With Merc's Top of the line oil and the Sea Foam, smoke is almost nonexistent. You have to look carefully to see any including when hole shooting.

HTH

Mark

SOP

 

[dozerII]

Re: Is there a test

Re: Is there a test

HTH ??? SOP ??? Thanks for the advise and suggestions. I have the seafoam in both areosol and regular. Just waiting for spring to arrive so I give it a good cleaning. Mark, What is the merc oil you are using ? I to was using a Merc oil in my last O/B a 1982 Evenrude 115 but it is $15.00 Cdn a liter. I am not sure on the part number for it, I will have to find an old receipt.

Glen

 

[Bob_VT]

Re: Is there a test

Re: Is there a test

SOP Standard Operating Procedure

 

[Texasmark]

Re: Is there a test

Re: Is there a test

HTH ??? SOP ??? Mark, What is the merc oil you are using ? I to was using a Merc oil in my last O/B a 1982 Evenrude 115 but it is $15.00 Cdn a liter. I am not sure on the part number for it, I will have to find an old receipt.

Glen

Since I can get it at WW I use it. I don't remember the Merc name (but if you need it, I can go out to the shop and get it for you), and they don't admit to it, but I'd bet my bippie it's either full or blended synthetic. Or I use TCW-3 synthetic which Pennzoil for one, manufactures and WW here stocks that too. I have used plain TCW-3 oils, but non-synthetics ( Merc TOL oil excepted as I don't know what it is) produce more smoke and more deposits. Since I can go out and have my fill of play for the day with 5 gallons of gas, the cost of oil is not a consideration.

Mark

 

[dozerII]

Re: Is there a test, New problem

Re: Is there a test, New problem

Thanks Mark, If you could get me the name that would be great, no Hurry. I started looking in the engine cowl a little closer and found the loer part is just full of a black oily goo. So I bit the bullet and took the pwer head off, as I already have the leg off. I foung th gasket on the exhaust cover is blown out at the bottom as the red circle in the photo shows. The other one just shows all the oily mess. I quess I am going to need the gaskets sooner than later.
PS Does clicking on the photo enlarge it for you?

Glen

 

[dozerII]

Re: Is there a test WHAT DO I DO NOW

AND IT GETS EVEN WORSE. What do I do now. As mentioned in the last post I was going to remove the exhaust cover and baffle plate ( I was going to wait till next days off but!!!) This is what I found. The photos Show #2 and 3 pistons. # 2 had 10# less compression 130 than the other 3 at 140 And it did this with out a top piston ring how is this possible?? 1st and 2nd photo are centered on #2 the third photo shows #2 on the right and #3 on the left. I really don't know what to do with this motor, scrap it and sell parts? The leg is complete with a entire new water pump, but does have bearing wear. I have over 30 years in auto repair and have never seen compression that close, when a ring is missing.
FRUSTRATION!!!!

 

[Texasmark]

Re: Is there a test WHAT DO I DO NOW

Geez, what a mess. I can't advise you on making your decision. 20 years ago I burned up a 3 cyl 70 hp rude to the tune of .030 over with new pistons/rings and other goodies. Cost was $1000 for the machinist (P+L turn key on the block) and I did everything else. When finished I had a sweet running little looper.

You have to weigh your odds and your desire for involvement. Parting it out could bring you some bucks, or you might find a used engine that has a good powerhead but has a problem with lower unit or something like that at a reasonable cost.

Keep us posted.

Mark