Exhaust Side Water Jacket question

[big_b16]

Hey all, I've got a question for some of the wrenches that frequent these parts. I pulled the exhaust cover plates to check things out. I noticed that there was more carbon buildup on 1 and 2 compared to 3 and 4. Is this normal, knowing that at idle 1 and 2 are used and 3 and 4 come on at higher RPMs. Also, the water jacket looks very dry on the right side, which might be due to me replacing those gaskets, t-stat, and poppet valve. I don't think there are any blockages. The last time this motor was running, it was fogged with sea foam. Thanks for the inputs. The engine is a 1996 Mariner 115 (0G348734). Also, what kind of paint should I use to cover any bare metal spots where the paint was removed when scraping the gaskets?

 

[Laddies]

Re: Exhaust Side Water Jacket question

The carbon is because it idles on the upper cyls. and the bottom don't run at idle

 

[Texasmark]

Re: Exhaust Side Water Jacket question

On paint, I never figured paint would standup to the joint so I used Alodine. You can get it at an automotive paint store. Ask them how to use it or go to www and ask a question like "How do you apply alodine to aluminum".

We used it at work to protect aluminum on aircraft. It's corrossive and provides a controlled corrosion surface on the alum which blocks further corrosion. Won't flake off or get corrosion under it like paint.

Mark

 

[big_b16]

Re: Exhaust Side Water Jacket question

Texasmark, if I only use this motor in fresh water, would bare aluminum get corroded? I primed and painted my water jacket cover but may pull it back off and remove that paint/primer. It was water resistant paint that was durable up to 200 degrees. In hindsight, I probably shouldn't have used it...unfortunately I used some steel wool to clean off the old gasket material and didn't pressure wash it to ensure any small pieces were all removed. If the paint flakes I don't think it would be good however. I don't think the paint was even an aluminum paint either...rustoleum (what was I thinking). I don't think the steel wool bits would be much of an issue since they will likely be circulated overboard in short time. What do you use to remove gaskets in the cooling system so you don't expose bare metal. If you can't use the alodine, etching, painting method via a spray booth or pressure sprayer, what other options are there? I could get into a paint booth if needed. Thanks for any insights.

 

[Silvertip]

Re: Exhaust Side Water Jacket question

Fogged with SeaFoam?? if you meant decarboned with Seafoam that's a valid use of the product. If you really meant fogged, then SeaFoam is not the product to use for that process. Fogging oil is a sticky oil used to coat the internals of the engine for long term storage.

 

[big_b16]

Re: Exhaust Side Water Jacket question

Acutally Sea Foam...Deep Creep, which has directions for fogging on the back. Which I too found odd, since Deep Creep is an aerosolized version of plain old Sea Foam...which is used as a decarb product (and a mild fuel stabilizer, fuel line cleaner, etc.). Any thoughts on my paint connundrum?

 

[Texasmark]

Re: Exhaust Side Water Jacket question

Big-B. In my opinion the main concern is getting a clean surface and adequate surface roughness for the paint to adhere to. On older engines, pre-existing corrosion can make that somewhat of a problem because of deep holes. Then when you paint, you really need a good primer like Zinc-Chromate (for Alum) to help and insure good contact to the alum.

You'll probably be alright. When I have been into engines, If I can't plan ahead and obtain the desired supplies, I tend to use what's available and part of that depends upon what it is and how important and durable the coating has to be.

Good luck,

Mark

 

[Laddies]

Re: Exhaust Side Water Jacket question

While painting gasket surfaces may help in saltwater or make some feel better, I just went to 6 of my newer Mercury manuals and the cleaning, inspection or assembly sections and no where is the use of paint or sealer recommended by Mercury Marine on any gasket surfaces. We work in fresh water here (Thank God) and in 45+ years I have never painted a gasket surface and never had a failure. Hope this helps

 

[Scaaty]

Re: Exhaust Side Water Jacket question

While painting gasket surfaces may help in saltwater or make some feel better, I just went to 6 of my newer Mercury manuals and the cleaning, inspection or assembly sections and no where is the use of paint or sealer recommended by Mercury Marine on any gasket surfaces. We work in fresh water here (Thank God) and in 45+ years I have never painted a gasket surface and never had a failure. Hope this helps

I gotta agree with Bob here (cold up there huh Bob?...rainy here at salty sea level..mountains getting nailed..I 90 over the Cascade pass been closed for on/off 4 days..getting FEET, not inches!)..anyway..gaskets are designed to conform to dips/roughness, etc. for sealing. Meant for bare, clean metal...Putting anything in the way defeats the purpose...

 

[big_b16]

Re: Exhaust Side Water Jacket question

Thanks guys. That is exactly the piece of mind I needed.

 

[Texasmark]

Re: Exhaust Side Water Jacket question

I gotta agree with Bob here (cold up there huh Bob?...rainy here at salty sea level..mountains getting nailed..I 90 over the Cascade pass been closed for on/off 4 days..getting FEET, not inches!)..anyway..gaskets are designed to conform to dips/roughness, etc. for sealing. Meant for bare, clean metal...Putting anything in the way defeats the purpose...

Yeah, well, I have batted that statement around all my life and I think carburetors are the only places I used dry gaskets. I use an appropriate sealer and have never had a problem. I may not have fixed 1000 engines in a repair shop, but I have kept all my equipment (and I've had a lot of it) running all my life with only a couple of trips to the shop to have something done I couldn't or wouldn't....most of which since I retired and got lazy.

One thing I like about adhesives is that they hold the gasket in place while you are attempting to get the thing together. Try leaning over the fender of a 454 Chev station wagon with a 75# head in your hand trying to stab it and get it right without creasing the gasket, by yourself.

I have actually had problems with dry head gaskets and never had a problem since using Kopper Koat which was made specifically for head gaskets. I know that one of the reason's adhesives are not recommended is that the sealer becomes part of the seal and the mfgr has no idea what type of sealer you are going to use so they must figure the best advice is put it on dry.

Problem you have with raw aluminum on dry gaskets is that you are relying on the gasket to seal the alum against the environment. Obviously it doesn't or there wouldn't be corrosion on my alum parts when I take things apart. I guarantee you, when you restore a 20 year old Mercruiser, you have holes that gaskets cannot possibly seal without some type of sealer. BTDT

Matter of fact, in Big B's picture, looks like somebody put adhesive on that gasket. If it were dry alum against a waterproof gasket, what is the mechanism whereby the gasket material we see sticks to the alum. Also, do I see corrosion on that cover? Looks like it along with the stuck pieces of gasket.

Carburetors are a good example. The carb castings are alodined and put together dry. When you dismantle a carb, the castings come off the gaskets clean to the point that in a tight you can even reuse the old gasket. BTDT

But, like motor oil and beer, to each his own.

Mark

 

[Scaaty]

Re: Exhaust Side Water Jacket question

Mark, I agree with the use of sealants where applicable...even if the book don't call for it.
And expierence and judgement helps.
Thing here is from what I gather, we are using paint.
Myself, I use Blue RTV on just about everything, or Red if oily Hi-temp.
Beer?...any kind, anywhere

 

[big_b16]

Re: Exhaust Side Water Jacket question

Texasmark, the gaskets from Mercury that I've gotten for the back waterjacket (and the ones I removed here) had a small bead of blue (silicone i'd imagine) material running through the gasket itself. They aren't dry like the carb gaskets. The shop I bought them from said if they had that bead, that RTV wasn't necessary. My motor surfaces seem pretty solid, no holes that I've found after removing the pieces and cleaning up the old gasket material. I may put a small bit of RTV on to hold them in place if it's needed, but with 4,432 or so bolts holding the exhaust plate and water jacket plate in place, there isn't much room for movement once all is lined up.

 

[Texasmark]

Re: Exhaust Side Water Jacket question

Well sir, they put it in there for you. I had a '97 350 Chev that had a plastic gasket (more like a spacer for the following) between it and the heads. Embedded in the gasket was a strip of silicon which apparently held the seal while the alum squirmed around on top of the cast iron heads.

Funny thing, the GM OEM gasket I removed wasn't nearly as fine a product as the aftermarket replacement. Forgot the mfgr, but they make a lot of gaskets and sets for the automotive world. Their quality was way up there. Obviously this would go on dry.

On paint, having fought corrosion in business all my career, it just didn't seem right to me to put an outboard together with raw alum on a surface that you wanted sealed. Just my preference.

Mark