Briggs 18HP V twin, Horizontal Shaft, Oil leak


  #1  
Old 06-28-11, 05:12 PM
M
Member
Thread Starter
Join Date: Jun 2011
Location: USA
Posts: 3
Upvotes: 0
Received 0 Upvotes on 0 Posts
Question Briggs 18HP V twin, Horizontal Shaft, Oil leak

Just replaced a head due to an exhaust valve that got stuck open by a displaced valve seat. Noticed while doing the job that there was a lot of oil mixed with grass etc. around the engine block, the head, etc. Replaced a corroded oil dipstick seal, but now I have it up and running (runs good) but I can see I am starting to accumulate oil around the flywheel end of the engine and over the area around the breather cover. There is also a coating of oil covering the inside of the air cleaner housing. If I had to guess, I would say the oil trickling down the front (flywheel end) of the engine is coming from up on top around the breather area. The breather is not occluded, as I can feel air rushing up through the rubber hose attached to it. Could all of this oil be coming from the breather gasket leaking, or is it likely I have bigger problems? As I said, this puppy runs quite well, and only blows white smoke if I occlude the breather (which I think is normal?).
Any help or suggestion as to how to troubleshoot this problem would be greatly appreciated. I plan on replacing the breather and gasket, but every trip to the BandS store is a long haul.

Thanks, Mysticheadlice
 
  #2  
Old 06-28-11, 09:37 PM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 15,837
Received 122 Upvotes on 112 Posts
A leak at that end of the engine gets blown around by the flywheel fan. If the oil goes up under the flywheel, chances are it's the top crankshaft seal leaking. If not, you may need to pressure wash the engine and watch for the early signs of leakage near gaskets and seals.
 
  #3  
Old 06-29-11, 07:26 AM
M
Member
Thread Starter
Join Date: Jun 2011
Location: USA
Posts: 3
Upvotes: 0
Received 0 Upvotes on 0 Posts
Briggs Oil Leak Woes

Cheese,
Thanks for considering my dilemma(s). A couple of questions:
1) Would a leaky breather gasket not be a possible cause for this oil?
2) My rubber tube that runs from the breather to the carb does NOT have a hose clamp on it (the B and S diagram shows one). Could that cause a leak?
3) This engine is on a Grasshopper, I have changed the crankshaft seal at the rear before, but I assume this front (?) one (under the fly wheel) would be a whole new kettle of fish, i.e can it be done without removing the engine from the mower frame?

Mysticheadlice
 
  #4  
Old 06-29-11, 09:24 AM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 15,837
Received 122 Upvotes on 112 Posts
1) yes, it's possible.

2) I won't say no, but it's unlikely.

3) Yes, it can be done without removing the engine.
 
  #5  
Old 06-29-11, 11:01 AM
M
Member
Thread Starter
Join Date: Jun 2011
Location: USA
Posts: 3
Upvotes: 0
Received 0 Upvotes on 0 Posts
Hey Cheese,

I may have to take you out to dinner or something for all this help you are giving. I really appreciate it. The people at B and S all seem to be unable/unwilling to answer the most basic questions- makes me wonder if I want to own their engines.
Anyway, one more question, and you may not know the answer. On this V-Twin, I'm looking at the breather unit on the parts diagram, and it appears I would just remove the one screw and it should come off. It doesn't seem to want to do that. There is this part in the diagram (Engine number 350447 1195E1) referred to as Baffle-Breather part #690686, I assume that sits under the breather. The edges of this baffle thing appear to be sort of curled up in the diagram which makes me wonder if the breather assembly slides into this rather than pulling off of it. Am I just not pulling hard enough to get the breather off, does the baffle just pull off with the breather?

Mysticheadlice
 
  #6  
Old 06-29-11, 05:48 PM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 15,837
Received 122 Upvotes on 112 Posts
Horizontal shaft. Those were the words I missed the first go-round.

The crankshaft seal probably isn't the problem in that case. The breather gasket may well be. Before taking the breather off, take a look at the breather tube closely. Is it cracked? Does it have oil/dirt caked all over it? If so, it may well be the problem. During running, oil can blow up into this hose, then when you shut it off, it can trickle back down and if it does not fit tight on the breather fitting, or if it has a crack in it, you will get a leak.

I have never seen the breather gasket cause a noticeable leak on one of these, but it could. I believe the breather just pops off after removing the one bolt. You may have to tap it on the side to get the gasket to break seal. If it is on there that good, that's an indication that the gasket may be doing its' job sealing it. Usually a leaky gasket lets go pretty easily.
 
  #7  
Old 03-08-13, 10:08 PM
K
Member
Join Date: Mar 2013
Location: usa
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
cheese
I have the same exact problem with an 18hp generac generator. I've already replaced the crank shaft seal behind the flywheel,and the breather seal. performed a leak down test as per local repair shop. No air getting by rings. BUT on start up oil starts slinging until the engine warms up.
Any ideas or suggestions would be helpful.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: