M35 Crankcase Breather Blow By

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Jhat
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M35 Crankcase Breather Blow By

i have found a really nice 2000 C36 MKii for sale that had a problem uncovered by the survey. It has a Universal m35B engine with 455 hours that is likely original to the boat. The surveyor described it as moderate crank case blow by. Smoke from the breather tube was white in color and started appearing at about 2000 rpm and increased up to maximum revs. The breather tube is not oily, just the blow by and the white smoke. The engine started started up easily and made good power driving the boat close to 7 knots into a 30 knot headwind at full throttle.  Judging by the condition of the boat and the low hours, I do not think this engine has been run very hard. 

For or those that know this engine is this somewhat normal or an indication to run the other way?

I am am wanting to get into a C36 and I thought I had found a good boat, now I have doubts, help!

Catboat Willy's picture
Catboat Willy
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Posts: 385

Jhat;
 This is a little hard to analyze via this forum but a certain amount of white smoke out of the breather tube is to be expected as the engine heats up. How hot was the engine when this was happening and when was the last time it was used ? It of course begets the question, how much smoke ? I am guessing that the breather tube is not terminated in to a oil catch container. If the boat had not been used in a while, there may have been some water in the oil system.
Two observations:
One;  455 hours seems like a very small amount of time for a twenty year old boat. 22 hours a year ?
Second; Before you spend that amount of money on this particular boat, hire a diesel mechanic to look the engine over. If you pay him $100 and hour, it will be well worth it.
To rebuild an M-35 engine will cost you in the neighborhood of $5,000. plus the hassle and time of extracting the engine and then re-installing it. In my experience, surveyors usually have to find something wrong with any boat they are surveying or you will not feel they are worth their fee. (no offence intended). Seldom if ever does a surveyor say ' 'This is a perfect boat' and usually leaves you with a bargining chip when buying the boat.
Try and find a diesel mechanic and let him evaluate the engine for you. Diesels that are used frequently, such as farm tractor engine that are used on a daily basis, are usually good for 10,000 and 20,000 hours. Engines that are seldom used seem to have a shorter life. ........ Good luck with your decision.
Bill

Bill Dolan 1990 Catalina C-36 MKI - Hull #1041  'Williwaw'
Std. Rig, Walk Through, Wing Keel
M35, Oberdorfer Conversion,
Home Waters; Charlotte  Harbor & The Gulf Islands of Florida
'You are never out of work if you own a boat'

 

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Siler Starum
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Posts: 113

First: A C36MKII is a perfect boat... no  conserns and no doubts about that. Believe this from a 2001 C36MKII user.
455 running hours for a 20-year boat is indeed not that much and if these hours are real you might have an issue caused by some internal corrosion because it hasn't been used so much. Sticky pistonrings??
Friendly spoken we had to do an overhaul of our M35B (1400 hrs) when we bought our Siler because of leaking cylinderhead gasket and a failure of LO-pressure sensor, but all to overcome and since the repair: "hit-and-run" and realy a reliable engine.
We forgot already the additional costs for the repair.... 
 

Durk Nijdam
S/V "SILER"
Catalina 36MKII - 2001 / hullnr. 2013
Stavoren - Holland

McFly
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Joined: 10/22/18
Posts: 200

My 1999 only had 484 hours of time on the Tach, which seemed way too low to be accurate.  And as my surveyor said, the only thing the timer on the tachometer tells you is how much time is on the tachometer.

Mike

Jackfish Girl, 1999, C36 MKII, Tall Rig, Wing Keel, In-mast furling, Monument Beach, Bourne, MA

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alfricke
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Posts: 90

Jubilee is a 2000 mkII #1867. I've put about 2000 of the 3000 hrs she has on her and know her well. I've never seen what you are describing, doubt that it is normal. Like others I'm guessing it is from lack of use. Good diesel mechanic is the way to get your question answered...could be a relatively inexpensive fix and you'd have a great boat!!!

Al Fricke
S/V Jubilee San Francisco Bay
Catalina 36' MkII  #1867
Universal 35-B

Haro's picture
Haro
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Posts: 403

Hi all,
I purchased my 1999 C36 10 years ago with 540 hours on the engine. Today it has 1300 hours on its display.
I have used it regularly, at least twice a month. I sail from San Francisco to Santa Cruz at least once a year and in most cases this 240 mile round trip turns out to require 75% of the time to just engine, due to low or no wind, usually when going back to north. Each 120 miles takes about 20 hours.
Currently my boat is in Santa Cruz as on the way back I had to deal with 8 to 10 foot waves and 40 knot head winds. So engining was the only way to move. Half way to Half Moon Bay - about 30 miles North of Santa Cruz, the engine RPM suddenly dropped from 2000 to 1000 and I heard loud pounding noise from the engine room. So I dropped to idle speed and placed the gearshift to neutral. The engine continued to run in neutral. So I reved up to see if the engine was having trouble - it reved up with no problem. Then I lowered to idle RPM and placed in forward gear and it started to moved forward. But as I increased the RPM to 2000, it started with the same loud knocking sound. Since the wind was blowing south I decided to return to Santa Cruz by raising the main at any way that I could.
I found that I could use the engine to propel the boat as long as I kept the RPM below 1500. I was able to re-enter the harbour and doc on my own power.
Today I went back to find out what I could find wrong. I ran the engine and heated it up to normal 160 F then put it in gear and reved up the engine to 2000 RPM for over 10 minutes.
The only thing that I noticed was there was blue smoke coming out of the breather tube - a light amount. I never heard the loud knocking sound. Everything worked as normal.
Interestingly enough today I found this post about the fumes coming out of the breather tube.
So what is the expected answer? Blue smoke spells trouble? I checked the oil level and it was normal. I am thinking that it appears to be burning oil. Or is this normal. If I could guess I would have to add one quart of oil per 2 months. There are no oily regions near the breather tube as the nearby air filter sucks the smoke in.
A white smoke would mean steam - I would think it is evaporating the moisture in the oil and it will stop when warm.
Has anyone observed their engine under load at 2000 RPM? Is there blue smoke coming out of the breather tube?
I am 120 miles from my home port. I would like to be able to engine back home where I can get help. Is it likely that I will be successful?
What are my choices?
I am also thinking that the engine may have been operating at heavy load and it could no longer handle the load due to large waves and high wind. The water temperature was always normal.
Thanks for your feed back.
 

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pkeyser
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Posts: 659

Unless you are consuming oil (blue smoke out the exhaust) or blowing white smoke out the exhaust (antifreeze/water), I would tend to think the engine is OK. Loud banging can be caused by a fouled fuel injector, or bad fuel (among other things). How does your fuel look? Any water and algae in the separator? Sometimes an injector issue will resove itself or be intermittent. Powering through rough conditions can break free sediment and contaminents in the tank. 

Paul & Wendy Keyser
"First Light"
Rye NH
2005 C36 MKII #2257
Wing, M35B

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Haro
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Posts: 403

pkeyser - you were correct about stirring up the crud that caused the blockage and fuel starvation. I was able to clean the residue that was accumulated in the trap under the primary fuel filter bracket and it is all OK now. The breather tube light smoke was normal.
Find more content visit http://mei1970.org/saillavie

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pkeyser
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Joined: 5/18/13
Posts: 659

Thanks for sharing your findings. Glad it was an easy fix!

Paul & Wendy Keyser
"First Light"
Rye NH
2005 C36 MKII #2257
Wing, M35B

Jhat
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Joined: 8/24/20
Posts: 4

I thought I would complete this thread with the findings.  I bought the boat knowing there was something wrong with the engine but with money in escrow from the seller to cover expenses.  During sea trials after the inspection, the engine made decent power but was 1000 rpms short of readline and did not run particularily smoothly and while it could push the boat at hull speed, there was nothing in reserve. The engine was pulled at the end of the season when the boat was hauled and I took it to a diesel repair shop. They put it in a stand and ran it, noting the same things I did during the sea trial.  The engine looks very good as it is a fresh water only boat with 455 or so hours on it.  

The bottom end of the engine was fine, good compression (like new) and the bores had no scoring or evidence of wear and the oil looked good when it was drained.  The problem was on the top, badly corroded injectors and a bad, corroded fuel pump.  Once these items were replaced, the engine ran well on the stand and they said it made good power.  Now I am waiting for spring and the engine will be reinstalled when the boat is relaunched.

Thanks for the help everyone.

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Ray Taylor
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Joined: 9/11/19
Posts: 81

Thanks for taking the time to detail the engine issue.  

Clean diesel fuel (for practical purposes) is considered non corrosive.   It becomes corrosive from the byproducts of bacterial growth.       Typically diesel becomes wet through condensation,  bacteria grow in the moisture, pH drops due to bacterial growth and things start to corrode.   

The point is that you may want to consider polishing the fuel in your tank to remove water and solids.    

Enjoy the boat,

Ray

Ray & Janice Taylor
"Mizu"
Hood River, Ore.
#2113 2002 TM
 

pierview
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Joined: 9/27/09
Posts: 582

Referring back to Haro's pictures, I was sailing into a harbor a few years ago when the RPM dropped suddenlly (but the engine didn't shut down). The RPM's picked up as I jiggled the throttle but then occurred as I approached the mooring. I changed the filters and the engine seemed to run fine but then, after about 4 hours of running, completly shut down as I was going through the Race.

I hadaan engine tech look at it and of course he expected the filters to be clogged.... they weren't  so he took the whole primary unit into the shop. The problem was in the 90 degree bend of the fule input line into the filter. It was clogged as per Haro's pics. He cleaned it out and I didn't have any problems after that but I draiined and cleaned my fuel tank that winter and it did have junk in it until it finally built up enough to clog the fitting BEFORE the fuel got into the filter itself.

I heartly endorse Haro's suggestion of cleaning out that connection when you change the filter! I ended up changing the fuel line when I cleaned the tank and I used extra hose so I could cut a little off each time I disconnected the line. It's sometimes hard to get the line off the coupling without slitting the end so this allows me years of snipping the end.
 

Chuck Parker
HelenRita 2072 Mk II
2002 Tall Rig - Winged Keel
Atlantic Highlands, NJ

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