The Ford Barn

MAG · 06-30-2010, 02:53 PM

I'm trying to locate pictures of the proceedure for installing the Center Main Bearing oil pipe. Any hep appreciated.

Blessyouboys · 06-30-2010, 03:09 PM

Might help if you provided a little more information regarding the engine you are building.

You do know the stock Model A engine had not provision for a center main bearing oil line?

Kurt in NJ · 06-30-2010, 09:34 PM

On the blocks that I have seen it done a pipe is made that goes from the center of the middle cam bearing to where the gravity pipe was in the main bearing saddle, usually with small compression fittings and copper pipe.

The pressure oil doesn't seem to help the cam bearing, it seems to have more wear than the front or rear bearings which just get splash and gravity ---but it does get first chance at all the dirt the pump picks up, the other bearings get oil that has had a chance for the large chunks to settle to the bottom of the valve chamber, all the oil pipes get oil at least 1/2" off the bottom. ---just my thoughts and ramblings, i have been measuring my selection of blocks to pick my next victims.

Barry in St.Paul · 07-01-2010, 06:28 AM

I've never seen a "book" method, but this is what I did, as guided by a mechanic in our Model-A Club. Rationale he had was that the center main takes twice the pounding because it is inbetween TWO cylinders instead taking the abuse of just one, like the front and rear mains. Not sure, but was easy enough to add and figured it wouldn't hurt anything and might help.

MAG · 07-01-2010, 09:52 AM

Thank you Kurt and Barry. That is exactly the info. I was looking for. Seems that I have seen this procedure written up (the Restorer/ Model A News)?? but after 50 years of playing with these cars my filing system (aka memory) is not maintained as well as it should be. Thanks again.
Here is how we did it

48Rob · 07-01-2010, 06:22 PM

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MAG · 07-01-2010, 08:16 PM

Thats a great idea Rob. Thanks for the picture.

quickchange · 07-02-2010, 03:05 AM

Rob, interesting, so does the rear main not receive preasure?? Is the pump altered at the top in any way? Does one need to fit a realease valve in the system? Thanks for sharing the info, Derek

James Rogers · 07-02-2010, 04:44 AM

The system shown does not actually pump much pressure to the bearings as shown. It only assures a slight pressure over the head pressure from the valve chamber. This issue can be resolved by blocking the top of the pump and installing a pressure valve in the lines. The bad part of this is that the valve chamber gets less or little oil if any, and as such, starvation of other systems (rear main) is probable. The reason the rear main is not plumbed is, the stock sealing system would be overwhelmed and a serious leak would result. This can be lessened by installing a modern sealing system but, none have been proven totally effective and leaks are still a problem. I do a center oil line but don't like to obstruct the main bolt so I bend the line to allow removal of the bolt without disturbing the line at the oil source which is the side of the oil tube at the pump.

Here is a picture of the type I use but with a different bend so the line does not cross the bolt head. This is not a picture of any motor I have ever built. I would NEVER wire the rod bolts like this.

Dave in MN · 07-02-2010, 11:40 AM

Quote:

Originally Posted by 48Rob

Rob...with your extended reach installation to the front bearing the use of steel tubing is prudent. How many miles do you have on this system.
Thanks for the photos!
Dave in MN

Doug Cox · 07-02-2010, 01:28 PM

as long as folks are posting pic of their center main, I might as well too. Just so you will know how common a practice it is..

Bruce · 07-02-2010, 02:10 PM

I have two engines set up for pressure oil to the center main. The location of the tap into the block/oil passage that the oil pump feeds is different in the two engines.
I bought the PRESSURE OIL CENTER MAIN BEARING kit from Piranio's in Denton Texas (www.modelaparts.net) and Dennis held my machinist's hand ... over the phone ... while he drilled the hole in the block.
Happy center main bearing, now!!

06-30-2010, 02:53 PM	#1
MAG Senior Member Join Date: May 2010 Location: Austin, Texas Posts: 925	Direct Oiling of Center Main Bearing I'm trying to locate pictures of the proceedure for installing the Center Main Bearing oil pipe. Any hep appreciated. __________________ I noticed the harder I work the luckier I get!

06-30-2010, 03:09 PM	#2
Blessyouboys Senior Member Join Date: May 2010 Location: Blissful Posts: 298	Re: Direct Oiling of Center Main Bearing Might help if you provided a little more information regarding the engine you are building. You do know the stock Model A engine had not provision for a center main bearing oil line?

06-30-2010, 09:34 PM	#3
Kurt in NJ Senior Member Join Date: May 2010 Location: on the Littlefield Posts: 6,195	Re: Direct Oiling of Center Main Bearing On the blocks that I have seen it done a pipe is made that goes from the center of the middle cam bearing to where the gravity pipe was in the main bearing saddle, usually with small compression fittings and copper pipe. The pressure oil doesn't seem to help the cam bearing, it seems to have more wear than the front or rear bearings which just get splash and gravity ---but it does get first chance at all the dirt the pump picks up, the other bearings get oil that has had a chance for the large chunks to settle to the bottom of the valve chamber, all the oil pipes get oil at least 1/2" off the bottom. ---just my thoughts and ramblings, i have been measuring my selection of blocks to pick my next victims.

07-01-2010, 06:22 PM	#6
48Rob Junior Member Join Date: May 2010 Location: Illinois Posts: 10	Re: Direct Oiling of Center Main Bearing Sponsored Links (Register now to hide all advertisements)

07-01-2010, 08:16 PM	#7
MAG Senior Member Join Date: May 2010 Location: Austin, Texas Posts: 925	Re: Direct Oiling of Center Main Bearing Thats a great idea Rob. Thanks for the picture. __________________ I noticed the harder I work the luckier I get!

07-02-2010, 03:05 AM	#8
quickchange Senior Member Join Date: May 2010 Location: Nelson. New Zealand Posts: 2,010	Re: Direct Oiling of Center Main Bearing Rob, interesting, so does the rear main not receive preasure?? Is the pump altered at the top in any way? Does one need to fit a realease valve in the system? Thanks for sharing the info, Derek

07-02-2010, 02:10 PM	#12
Bruce Senior Member Join Date: May 2010 Location: Sun City West, AZ Posts: 489	Re: Direct Oiling of Center Main Bearing I have two engines set up for pressure oil to the center main. The location of the tap into the block/oil passage that the oil pump feeds is different in the two engines. I bought the PRESSURE OIL CENTER MAIN BEARING kit from Piranio's in Denton Texas (www.modelaparts.net) and Dennis held my machinist's hand ... over the phone ... while he drilled the hole in the block. Happy center main bearing, now!!