Author |
Message |
Combinations Samba Member
Joined: March 19, 2010 Posts: 286 Location: Massachussets
|
Posted: Mon May 06, 2019 9:55 am Post subject: Oil leak in the |
|
|
There is an oil leak on my 76 bay window bus engine. Right on the bolt that hold the fan. I can see oil all around. Not a lot, but When I drive it smells like burning oil.
I was wondering if it could:
1) come from crank shaft seal behind the fan
2) the oil pump?
Any idea?
Thanks
Aurel |
|
Back to top |
|
|
Wildthings Samba Member
Joined: March 13, 2005 Posts: 50348
|
Posted: Mon May 06, 2019 10:07 am Post subject: Re: Oil leak in the |
|
|
Lots of potential sources, it would help if you would give us the history you have on this engine. Is the rig new to you? Did the problem just start? What recent work has been done on the engine? Is your crankcase ventilation all there and checked to see that nothing is clogged? |
|
Back to top |
|
|
SGKent Samba Member
Joined: October 30, 2007 Posts: 41031 Location: Citrus Heights CA (Near Sacramento)
|
Posted: Mon May 06, 2019 10:11 am Post subject: Re: Oil leak in the |
|
|
as Mike said, lots of potential sources. Be sure your breather works. _________________ “Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin |
|
Back to top |
|
|
volksworld Samba Member
Joined: November 26, 2011 Posts: 2529 Location: formerly NY currently NC
|
Posted: Mon May 06, 2019 5:16 pm Post subject: Re: Oil leak in the |
|
|
the fan attaches with 3 bolts to the fan hub....the fan hub is tapered and attaches to the end of the crank with one bolt in the center, and a woodruff key so it aligns properly....there is a seal that goes into the the block that rides on the fan hub(021 105 247a), and there is also an o-ring behind the fan hub that prevents oil from leaking between the hub and the crank...which would most probably cause oil to appear at the center bolt if its dried out or missing...the tapered fit of the hub requires a puller to remove it to change either seal...any leaks in that area can get sucked into the fan and get blown all over the place, including oil cooler seals or a bad oil pressure switch ...and pushrod tube o-rings and valve cover gaskets can leak onto heater boxes and really smell
Last edited by volksworld on Tue May 07, 2019 3:56 pm; edited 1 time in total |
|
Back to top |
|
|
alman72 Samba Member
Joined: October 09, 2014 Posts: 2573 Location: MICHIGAN
|
Posted: Tue May 07, 2019 7:12 am Post subject: Re: Oil leak in the |
|
|
the spinning fan can make a mess of any nearby leak. |
|
Back to top |
|
|
Combinations Samba Member
Joined: March 19, 2010 Posts: 286 Location: Massachussets
|
Posted: Thu May 09, 2019 4:55 am Post subject: Re: Oil leak in the |
|
|
Thanks guys for these info. Ok to make it short:
-Purchased the bus with engine out.
-The engine was rebuilt by a mechanic and had a dual carb, crank... and all the stuff that makes it ''stronger''
-I installed the engine and drove it for 2000 miles.
-Found that oil leak in the fan area ( some oil right in the center of the fan where the bolt is.
-Clean everything to try to spot if the oil come back after running it for 20 minutes.
I just found a leak at the top of a con rod pipe seal, at 4th cylinder I think ( left on close to the fan)
That's where I am now. Here are some pics.
|
|
Back to top |
|
|
Zed999 Samba Member
Joined: March 04, 2018 Posts: 1247 Location: UK
|
Posted: Thu May 09, 2019 5:45 am Post subject: Re: Oil leak in the |
|
|
Oil in the centre, or if you prefer "intake" side of the fan has come from outside the engine and been sucked there by the fan.
I see that instead of an oil breather plumbed to an air filter, somebody had fitted a small filter. Bad. Bad for at least two reasons...
1. I bet it's by now visually soaked and dripping oil. If not it soon will be. When the engine is running it will spit out a mist of crankcase oily horror.
2. The oily mist is being sucked into both fans, heated by your heat exchangers and pumped into the cab for heating. Not good for the occupants. |
|
Back to top |
|
|
Wildthings Samba Member
Joined: March 13, 2005 Posts: 50348
|
Posted: Thu May 09, 2019 6:02 am Post subject: Re: Oil leak in the |
|
|
Having a breather setup like you do is going to cover everything in the engine compartment with oil over time. I personally would vent the crankcase into the top of one of the air cleaners so the oily blowby gas gets consumed by the engine as per what has been the automotive norm since the 1960's. The vent hose needs to be routed so it has continuous slope otherwise it will clog with engine snot over time.
If you do have oil coming from the fan hub area, then remove the fan and the hub and check/replace the o-ring that fits behind the hub. You could replace the shaft seal for the fan hub at the same time if you feel there is any possibility that it is the cause of the leak. |
|
Back to top |
|
|
SGKent Samba Member
Joined: October 30, 2007 Posts: 41031 Location: Citrus Heights CA (Near Sacramento)
|
Posted: Thu May 09, 2019 7:21 am Post subject: Re: Oil leak in the |
|
|
anytime the breather is inadequate it will cause pressure to build in the crankcase when under load, and force oil out other places. Get the breather fixed first. _________________ “Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin |
|
Back to top |
|
|
Combinations Samba Member
Joined: March 19, 2010 Posts: 286 Location: Massachussets
|
Posted: Thu May 09, 2019 7:41 am Post subject: Re: Oil leak in the |
|
|
Ok I see, what is the correct air breather I should mount? ( any picture or link) I am used to split and don't know these engines. Thanks guys! |
|
Back to top |
|
|
Combinations Samba Member
Joined: March 19, 2010 Posts: 286 Location: Massachussets
|
Posted: Thu May 09, 2019 8:09 am Post subject: Re: Oil leak in the |
|
|
Wildthings wrote: |
I personally would vent the crankcase into the top of one of the air cleaners so the oily blowby gas gets consumed by the engine as per what has been the automotive norm since the 1960's. The vent hose needs to be routed so it has continuous slope otherwise it will clog with engine snot over time.
|
Do you have by any chance a picture that could help me visualize the configuration?
Thanks
Aurel |
|
Back to top |
|
|
Wildthings Samba Member
Joined: March 13, 2005 Posts: 50348
|
Posted: Thu May 09, 2019 9:34 am Post subject: Re: Oil leak in the |
|
|
Combinations wrote: |
Wildthings wrote: |
I personally would vent the crankcase into the top of one of the air cleaners so the oily blowby gas gets consumed by the engine as per what has been the automotive norm since the 1960's. The vent hose needs to be routed so it has continuous slope otherwise it will clog with engine snot over time.
|
Do you have by any chance a picture that could help me visualize the configuration?
Thanks
Aurel |
This is the air cleaner lid and breather hose on my 1800. The hose just runs from the breather box on the engine and dumps through the air cleaner lid right above the venturi. I just used a grommet and plastic elbow available at most any hardware store.
|
|
Back to top |
|
|
Combinations Samba Member
Joined: March 19, 2010 Posts: 286 Location: Massachussets
|
Posted: Thu May 09, 2019 10:49 am Post subject: Re: Oil leak in the |
|
|
Excellent, merci! Good inspiration! |
|
Back to top |
|
|
|