So I'm all in my head about the amount of smoke or vapor that is coming out of my exhaust. It doesn't happen until the boat is warmed up and under a load of about 2200+ rpm. The video is once the engine is warmed up and I'm cruising along at about 2500rpm. I've noticed this before but am unsure if this is a normal amount and nothing to worry about as other m25 motors I've had did not smoke/water vapor.
Just looking for some group wisdom here in chasing this down!
Short video: https://youtu.be/uBJAgaRxaeY (https://youtu.be/uBJAgaRxaeY)
Boat Details:
1988 Catalina 34
Universal M25xp W/ approx 2000 hrs (I know history on engine going back to about 600 hrs)
10x15 prop
Bottom cleaned a couple months ago
New injectors
Recently adjusted valves
New kubota freshwater pump
Rebuilt Oberdorfer N202m
Filters changed religiously
currently running a Kubota 160 thermostat
Would you classigy it
white smoke
darker smoke
water vapor
Whats the air temp and humidity (vs other times w/ no "smoke".)
Att that can be important in answrig the questions
]-k
Sloopdog,
When motoring along I get the occasional wisp of steam, and I have been since I got the boat in 1988. I couldn't run the video but from the picture it looks like yours is about the same as mine. Unless it's billowing clouds of steam I wouldn't worry about it to much. The important things to keep an eye on are the temp gauge and your coolant level, if those things are normal you should be good.
If you run the engine at those rpm while at the dock, the exhaust will be easier to see and examine.
Ours runs clean, no smoke or steam, at 2000 rpm (max of 2100 rpm on ours) but if we rapidly change engine speed then we get dirty grot blowing out.
We replaced the injectors and tubes last year and had the injector pump rebuilt at the same time.
Paul
Sloop : As Ken points out - the color of the smoke ? is the key!!
A thought
Extremely late followup here but I've moved the video over to Youtube so everyone should be able to easily view.
https://youtu.be/uBJAgaRxaeY (https://youtu.be/uBJAgaRxaeY)
To answer some of the questions posed:
- I would classify as white but take a look at the video.
-Water temperature is about 50 degrees always (San Juan Islands, WA). It seems to be present at all ambient temperatures I've been in but video was probably 65F to 75F
-Only happens under load once the motor is warmed up. Is constant unless I'm under 2000 rpm.
-With thermal gun the temp of my exhaust tubing at the thru hull is less than 100F. Temp on Engine thermostat area is right about at 160 regardless of rpm.
I appreciate any ideas or thoughts even if it's "don't worry about it and go sailing", which is partially why I haven't been able to follow up!
Sloop : I looked at the video on U-tube and it looks like steam to me!! I believe that it's the atmospherics and wouldn't worry about it.
Probably is happening on your auto, you just aren't looking backwards to see it!!
A thought
Quote from: sloopdog on September 01, 2020, 02:42:20 PM
I appreciate any ideas or thoughts even if it's "don't worry about it and go sailing", which is partially why I haven't been able to follow up!
OK, I'll bite: "don't worry about it and go sailing" :D
Really. Why? We've had our boat for 23 years, sailed 1998 to 2016 in San Francisco, sailed up here in 2016. Never had that "stuff" come out the back "down there." "Up here", it's NORMAL. Not an issue.
Go have fun, no excuses now... 8)
Quote from: sloopdog on September 01, 2020, 02:42:20 PM
- I would classify as white but take a look at the video.
I'd buy a color wheel! That's not white smoke, it's water vapor No issue.
Sloopdog,
If you're looking for a problem it's possible you could have a vane broken off from the impeller. A few years back I had a couple of vanes caught in the cooling system, it caused it to steam a bit more than normal but the engine temp never changed. When I pulled the heat exchanger to clean and paint it I also tracked down the broken vanes and removed them. The thing is I knew they were in there but didn't bother with them until regular maintenance provided an opportunity. Since you don't know and your running normally I wouldn't worry about it.
Ha I guess that's all the confirmation I needed to file it under don't worry about it. I appreciate the responses!
in response to scgunner I did burn up an impeller last year but replaced and also rebuilt the entire pump. I'm pretty sure I pulled all the vanes out of the elbow but there could be more in exchanger. Regardless, I've pulled hoses downstream and I have plenty of flow through there.
Thanks all for the input.
Sloop : You might think about pulling the HX and opening it up; and see what "treasures" are inside like impeller blades and old chunks of Zinc!! :shock:
A thought
I'll second Ron, if it's been awhile you might think about pulling the HX to check, clean, flush, and repaint the unit, but I'd probably tie it into your next 100hr service. Also, I'd check that zinc regularly, if it goes away corrosion will attack your HX and that's an expensive replacement. I check mine once a month, but I may be a little paranoid.
Thanks I will get to the HX during the winter. It has been on my list but hasn't quite risen to the top yet. I know it's a new 3 inch version installed probably 4 years ago and hasn't been pulled since. I replace the zinc at least a couple times a season as I've also heard stories of how they corrode rather quickly and break off in there.
Sloopdog,
Regarding that zinc, a lot depends on where you're at(even in the same marina)and who your neighbors are. I've been moved around in my marina and had numerous boats of all kinds as neighbors in the 30 or so years I've been there. One thing I've learned is based on those factors and probably others is there's noway to predict how long the zinc will last, sometimes the zinc will be gone in a month or two and sometimes the zinc has lasted well over a year. That's why I check mine once a month.
SD,
A zinc a couple times a year seems excessive. Does the marina check periodically for stray current in their ground lines to try to locate offending boats? it seems to me that there is a leakage issue there somewhere. Have you checked yours for leakage? It shouldn;t be eaten up that quickly. You will want to bond your Hx to a known good ground (if it's not already) to make sure it has the utmost protection against galvanic corrosion.
ken
Ken,
I don't normally have to replace my HX zinc every 6 months, they usually last around 1 to 2 years, however there have been times when I've had to replace the zinc in two months or less, which is why I do a monthly check. I think if there was a problem with my boat the rapid burn rate of the zinc would be a lot more consistent. As far as the marina I'm in, the only thing they seem to be really good at is billing marina occupants. You're right,it shouldn't be eaten up that quickly, but sometimes, due to constantly changing conditions in the marina, it does.
Kevin and SD. Is your 12v negatives bonded to your shore power green ground? IIWMB I'd check for stray current just for peace of mind. I treat the zinc as a symptom and a last-chance firewall, not a solution.
Ken,
In my case I doubt there's a problem with the shore power since my marina was completely rebuilt(wood docks to cement)a couple of years ago. Also since the burn rate on my zincs currently seems normal I don't see the need to go looking for a problem that's not really there. And I thought zincs were the solution---to galvanic corrosion. It's just a question of burn rate which goes to my original point to keep an eye on the zincs since the burn rate can be influenced by a number of factors besides just a bad ground.
Kevin,
I took it that it was more variable so there might be an intermittent issue.. Certainly if you are happy with checking and using the zinc as the solution who's to second guess that.
-k
Just to clarify for others,
Understand that marina AC wiring doesn't cause galvanic corrosion (well normally anyway.) It transmits the corrosion.
And brand new, perfect, marina wiring can exacerbate, not reduce that corrosion.
In some situations, poor marina wiring could reduce the galvanic corrosion between boats.
Just because a Hx anode (zinc or magnesium or aluminum) corrodes rapidly (or if it lasts forever) doesn't necessarily reflect what's going on with the total picture. Two different metals in an electrolyte (e.g., water) essentially create a DC battery. The indication of the Hx anode can be completely separate (i.e., the Hx is sitting as a completely separate battery) from other metals on the boat that may galvanically corrode. Or the Hx could be completely reflective of the overall situation. It depends on what is, and is not, bonded.
Galvanic corrosion depends on an electrical connection -- non pffeding boat(s) can have an intermittent connection(s.) Or the offending boat(s) can have an intermittent connection(s.) Or both could.
-k
In regards to changing the HX zinc a couple times a year I'm sure it's a bit overkill. The one I remove likely has a lot of life left in it but the replacement zincs that screw into the cap are cheap enough I like to just stay ahead of it and not risk losing one into the hx. I'm still trying to get used to maintenance schedules out in the saltwater vs when I was on the fresh side of the locks down in Seattle. Growth and saltwater seem to create some increased maintenance.
Quote from: sloopdog on September 13, 2020, 05:16:23 PM
In regards to changing the HX zinc a couple times a year I'm sure it's a bit overkill. The one I remove likely has a lot of life left in it but the replacement zincs that screw into the cap are cheap enough I like to just stay ahead of it and not risk losing one into the hx. I'm still trying to get used to maintenance schedules out in the saltwater vs when I was on the fresh side of the locks down in Seattle. Growth and saltwater seem to create some increased maintenance.
Good points. Things DO change when you move your boat, even in saltwater to saltwater. I used to have to change my zincs 4 times a year in California, same marina, same slip for 18 years, but the boats around me, except for my next door neighbor to starboard, changed regularly. Once I moved here to BC, I have found 2 times a year works fine, same slip for 4+ years, neighbors change even more often, and the electrical "system" at my marina is kinda a joke. :D
Just keep checking them and you'll find out what "your" schedule needs to be.
Guys : Now that we have morphed off in to Zincs.
If you are new to your C34 always check the depth that you Zn goes into the HX. On my old engine I found that when I put a #2 pencils in to that hole that it would stop in about 2 1/2 inches. The inside of the HX tubing stopped anything past that depth. I had to cut off about 3/4" off a new Zn to make sure it would fit!!
Moral of the story is to check that depth needed with a pencil or screwdriver to make sure that you are not forcing a new Zn against the internal tubing.
A thought
The original HX that came on my boat didn't allow a full length zinc to be inserted, I also had to cut to fit. The replacement HX does allow for installation of a full length zinc. I think there was a design change down the road.
When I got both of my new 3 inch HXs, I took off the end caps to see what zincs would fit it, so I KNEW. (In an earlier thread I discussed that I needed a second one because the bracket rubbed the first one and penetrated the shell. My thread is in the 101 Topics under Good Guys - Sendure.)
Here's OEM anode info that I had gathered over 25+ years (some p/ns and prices may have changed since I last checked them - I removed all the WM SKUs I had because they are all changed now.)
If your anode takes the following wrench, it tales the corresponding anode:
7/16" wrench (see #1)
11/16" wrench (see #2)
9/16" wrench (see #3)
Three caveats:
1) These are for the correct OEM Hx, if a different Hx is installed your mileage may vary.
2) If your end cap bolt is in the way - don't cut your anode just, 'er, get a shorter bolt.
3) These are old info, if anyone finds errors I will correct and wiki post it.
(#1)
*****
M-25; 2" Hx
Anode length: 2", Dia 1/4" / 1/8" NPT - plug 1/4" UNC; 7/16" wrench for hex head
Zinc anode w/ plug
Universal p/n 301069
Canada Metal p/n CME00 / UPC: 10628309103191 / Substitute for Universal p/n 301069
Anode only, CMEZ00 / $2.99
(#2)
****
M3-20
M-25/ M-25XP; 3" Hx
Anode length: 1-1/4", Dia 1/2"; NPT: 3/8" - Plug 3/8" UNC / 11/16" wrench for hex head
Zinc anode w/ plug
Universal p/n 301068
Canada Metal p/n CME1F / Substitute for Universal p/n 301068
Anode only, CMEZ1F / $1.79
(#3)
****
M-25XPB; 3" Hx
Anode length: 1 3/4" Dia 3/8" 1/4" NPT - Plug 5/16" UNC / 9/16" wrench for hex head
Zinc anode w/ plug
Westerbeke p/n 11885
Canada Metal p/n CME0 / Substitute for Westerbeke # 11885
Anode only, CMEZ0 / $2.99
Quote from: KWKloeber on September 14, 2020, 08:52:36 PM>>>>>>>>>>>
If your anode takes the following wrench, it tales the corresponding anode:
7/16" wrench (see #1)
11/16" wrench (see #2)
9/16" wrench (see #3)
>>>>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>>>
Good summary. However, I have found that my 11/16" nut can take two different sized zincs, a fat one and a skinny one. Guess one size fits all doesn't necessarily apply. I switched to a 3 inch HX years ago on my M25. I use the skinny ones because I found that the fat ones, as they start disintegrating (as they should), are harder to remove from the hole.
Stu,
I agree on the fat and skinny of the zincs, I use the fatty just because I like having more meat, even though you're right, it can be a bit of a pain extracting it. Also I'd avoid the Chinese zincs, they're poorly made and very hard to screw into the brass nut and all but impossible to get out so it's usually necessary to replace the whole unit.
Check the threads on the zinc before using. I found the threads usually have excess material at the parting line from the casting process so they don't screw into the nut right. I use a small file to clean up the threads and they work fine.
Or you can use American made zincs that just screw in finger tight and can be replaced almost as easily.
Sounds like an issue I just went through a few days ago.
Had motored for 11 hours, full load, from Seattle to Anacortes. No smoke. Sailed around for a couple of days in the San Juan Islands, and then when motoring on a longer passage noticed smoke coming out of exhaust, and some slight increase in water temp from the normal 160 to 165-170. Color: white, gray, dark gray...
Shut everything down mid-channel. Checked raw water strainer: clear. Probed raw water through hull with a long piece of thin dowel: clear. Whats up?
Starts normally, no smoke. Run it up to 2000-2200, and after a while smoke. Hmmm.
Called a mechanic in Friday Harbor and explained. He came over and thought was carbon build up in the exhaust riser. I told him it was new 18 months ago and is stainless. Tells me to start the motor in gear, run it hard, purge the carbon, blah, blah, blah...
Watched it for a few more days and experimented. Running continuously at 2000-2200: smoke. Run it over 2500 (1) smoke and (2) jump in water temp to 165-170.
Back down to the raw water strainer. Took off bowl: clear. Re-attached, tightened (not all the way) and watched the bowl while I opened the raw water through hull. Ah, slow to fill--too slow. Probed the 90 degree inlet elbow to water strainer from raw water through hull. Had to remove hose connecting the two first. Voila: eel grass creating a blockage in the elbow before the raw water strainer/basket.
Put it back together. Ran it for 10.5 hours yesterday from Anacortes back to Seattle at 2500-2700 rpms. No smoke. None.
Problem (smoke/sooty stern) appeared to be caused by reduced water being pumped because of the blockage in the inlet elbow to water strainer and then injected at the exhaust riser before the water lift muffler. More hot dirty exhaust, and not enough water, being spewed out the back.
Not sure this helps, but thought I would describe what I found.
Patches
Patches : Been thru that a number of times, but mine were complete clogs!!
That's why I "caulked" a round bronze strainer onto the hull to cover the raw water inlet. That was in 1996 - never had a problem sense!!
"Caulked on", because if it ever presented a problem - all I had to do was take wooden dowel and punch it off from the inside!!
(which has never happened!!!) :thumb:
A thought