merc 650 lower bearing check valve ?

[Yachtzee]

I do not know how I would hadnle this engine without this forum!

I have a 67 merc 650 4. The lower crank bearing was really rough,
I notice on a parts diagram that I found ( the website for BAM), that a check valve is called out for the lower bearing carrier, but the part is unavailable.
I would guess that this may have been a ball baring thing that should live in a hole bored in that carrier? Is that a good guess or am I off base?
Was there a spring associated?
The tube running up from the lower end of the case to the main bearing that should function as a check valve too is that correct?
I am going to put some bucks into this thing and I do not want fry bearings down the road due to my ignorance.
Thanks mcuh for the continued help
Yachtzee

 

[Laddies]

Re: merc 650 lower bearing check valve ?

It's been awhile but if I remember right the there should be a hole that removes the oil that has puddled either between the bottom and top seals of the bottom main or just above the top seal and under the brg. The purpose of the bleed was to prevent number 4 cyl from puddleing oil at idle the ck would hold the oil in the bleed tube so if you shut the engine off it would not all run back into the lower cyl. In most cases you can clean the ck valve by blowing some WD40 thru it. If not there are many donor engines around it don't have to be a 650 4 cyl any inline will work

 

[Chris1956]

Re: merc 650 lower bearing check valve ?

Yachtzee, My '77 6 cylinder inline had a checkvalve on the lower crankcase, transfer port side. This was connected to a brass fitting on the top of the crankcase, via a thin rubber hose. If your fittings are the same, they should be available at any junk yard. I alos have a set that I am not using.

You should check www.dougrussell.com and see if you can match up some part numbers from your 650 to a newer motor.

 

[Yachtzee]

Re: merc 650 lower bearing check valve ?

Chris and Laddies,
Thanks for your replies and ongoing help!
The "thingy" I am referring to is item 27 PN 21 - 28481A 1 on Doug Russells parts list for the merc 650 ser# 2207362. On a parts diagram it is called a check valve the arrow points to the side of the bottom end cap or bearing carrier what ever you call it. I see a hole a bit less than 1/4 inch drilled into the side of the cap, it is about 1/2" deep and is bored with a tiny outlet at the bottom where it feeds into the bearing, (which was toast) and lines up with a passage in the case that connects to the elbows and hose outside the block.
If there was any kind of valve a ball etc in there it got lost when I popped the cases apart. can either of you visualize if there should be something inside that hole, the part whatever it is is $30+

Thanks

 

[Chris1956]

Re: merc 650 lower bearing check valve ?

That fitting for my '77 Merc 1500 is $50+ at Doug Russell. I cannot tell if it will fit from just looking at the picture and the part number is different.

My Memory says that the fitting is a one way valve which allows oil thru it into the bleed hose and pumps it to the top bearing. I think it has a BB to give it the one-way property. You might just use any standard plumbing fitting, since it should not have a great effect on the running of the motor.