Join the C34 Association Today!
[C34 Home] [C34Tech Notes] [C34 Tech Wiki] [Join!]
Please login or register.
Advanced search  

News:

Pages: [1]   Go Down

Author Topic: Universal M25 diesel problems  (Read 286 times)

0 Members and 1 Guest are viewing this topic.

frogdoc58

  • Forum - Seaman Apprentice
  • *
  • Karma: 0
  • Posts: 10
    • View Profile
Universal M25 diesel problems
« on: July 03, 2020, 06:47:35 PM »

Hi All,

I have an '89 Catalina 34 with a Universal M 25 diesel.  On the top of the engine next to the coolant tank is what appears to be a crankcase vent.  Currently when the engine is running there is an oily vaper coming out of it.  The vent has threads, maybe 1/2 inch JIC.

My questions are, is the discharge normal if so is there supposed to be a vent hose attached and if so where does it got to?  Also, when I put my finger over it, pressure builds up.

Can anyone give me some advice.

Thanks,  Paul
Logged

Jon W

  • Administrator
  • Forum - Chief Petty Officer
  • ******
  • Karma: 10
  • Posts: 882
    • View Profile
Re: Universal M25 diesel problems
« Reply #1 on: July 03, 2020, 07:48:42 PM »

Most of us connect a hose and route it to discharge into the engine air filter. Depending the type of air filter some tie wrap the hose to the injector tubing, some drill a hole in the top of the air filter and attach a hose fitting to connect the hose, and some have routed the hose to an air/oil separator then to the air filter.
Logged
Jon W.
s/v Della Jean
Hull #493, 1987 MK 1, M25XP, Manson Supreme 35
San Diego, Ca

Stu Jackson

  • C34IA - Secretary
  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 69
  • Posts: 7629
    • View Profile
Re: Universal M25 diesel problems
« Reply #2 on: July 03, 2020, 08:38:12 PM »

Paul, welcome.  Here's what Jon was talking about:

Breather Hose 101 (w/ K&N Filter Pictures from Rick Allen)

http://c34.org/bbs/index.php/topic,8875.msg63915.html#msg63915

and Noah's:  http://c34.org/bbs/index.php/topic,8858.msg64297.html#msg64297
Logged
Stu Jackson, C34 IA Secretary, #224 1986, "Aquavite"  Cowichan Bay, BC  Maple Bay Marina  SR/FK, M25, Rocna 10 (22#) (NZ model)

"There is no problem so great that it can't be solved."

frogdoc58

  • Forum - Seaman Apprentice
  • *
  • Karma: 0
  • Posts: 10
    • View Profile
Re: Universal M25 diesel problems
« Reply #3 on: July 03, 2020, 08:42:33 PM »

Wow, that's a great solution.  I will be getting right on it in a few days.

Thank you very much.

Stay safe and have a great sailing summer, well as best as you can right now.

Regards, Paul
Logged

KWKloeber

  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 32
  • Posts: 3567
  • "Positive Impact" 1984 C-30 #3573 trbsfk M-25
    • View Profile
Re: Universal M25 diesel problems
« Reply #4 on: July 03, 2020, 08:59:38 PM »



is the discharge normal if so is there supposed to be a vent hose attached and if so where does it got to?  Also, when I put my finger over it, pressure builds up.



Paul

Look at pg 12 of your M25 parts manual that I know you have downloaded and keep handy.  It shows the vent hose (which OEM just hangs into the bilge.)

There shouldn't he a huge amt of oil/gunk come out at any one time but over time it will and will stink up the bilge/boat.  This has been covered many times on the forum if you do a search.

Yes the will be a slight pressure but if you have excessive pressure/oil/gunk you could have excessive ring blowby (check the engine compression.)

If you check the tech wiki site under >>engine<< there are a few suggestions how to route the crankcase vent to the air intake.  Below is mine.  Another way not discussed is to drill. tap, and use a hose barb on the intake manifold.  The XPB has a knockout on the intake manifold to accept the crankcase vent hose.

-ken
Logged
Twenty years from now you'll be more disappointed by the things you didn't do, than by the ones you did.
So throw off the bowlines.  Sail away from the safe harbor.  Catch the tradewinds in your sails.
Explore.  Dream.  Discover.   -Mark Twain

frogdoc58

  • Forum - Seaman Apprentice
  • *
  • Karma: 0
  • Posts: 10
    • View Profile
Re: Universal M25 diesel problems
« Reply #5 on: July 15, 2020, 10:16:56 AM »

Thank you all for your help.  I made the modification.  No more smoke and oil mist coming into the engine compartment.
I'm sure that I am getting excessive blow by, rings, but for now I will get through the season.

Cheers for now,

Paul
Logged

Ron Hill

  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 55
  • Posts: 7012
    • View Profile
Re: Universal M25 diesel problems
« Reply #6 on: July 15, 2020, 12:20:09 PM »

Ken : Have you looked at the belt alignment in your picture??   :shock:

A thought
Logged
Ron, Apache #788

frogdoc58

  • Forum - Seaman Apprentice
  • *
  • Karma: 0
  • Posts: 10
    • View Profile
Re: Universal M25 diesel problems
« Reply #7 on: July 16, 2020, 08:20:03 AM »

That's not my actual engine.  But I do see what you are seeing, the belt looks to be upside down.  Good eye.
Logged

KWKloeber

  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 32
  • Posts: 3567
  • "Positive Impact" 1984 C-30 #3573 trbsfk M-25
    • View Profile
Re: Universal M25 diesel problems
« Reply #8 on: July 16, 2020, 12:41:39 PM »

Ron: That's an OLD pic and I think there's a slight fisheye effect from the lens, but I will check it.  THX!!
I plan some upgrading so it may be moot soon.


Paul:  I find that my belt rides MUCH better when it's turned inside-out.***
Scroll down
                VvVvVvVv







***(Actually it's a dayco "top cog," recommended for our small alternator pulley.) 


Logged
Twenty years from now you'll be more disappointed by the things you didn't do, than by the ones you did.
So throw off the bowlines.  Sail away from the safe harbor.  Catch the tradewinds in your sails.
Explore.  Dream.  Discover.   -Mark Twain

Ron Hill

  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 55
  • Posts: 7012
    • View Profile
Re: Universal M25 diesel problems
« Reply #9 on: July 16, 2020, 02:22:04 PM »

Paul : FYI, the cogs on the belt are for - Cooling.

A thought
Logged
Ron, Apache #788
Pages: [1]   Go Up