Rod Bearing Confusion!!!!

[Zap]

In the middle of the rod bearing job and I come upon this situation that makes me feel a bit weird about things...

I just got done installing 5 of the 6 sets of bearings when I discover writing on the bottom of the old bearings. There is a little symbol plus some type of part #. All 5 of the bearing sets from front of engine to rear have the part number D4H. The last set of bearings, however, has the part number D4D. eek! I am worried that this may be a different clearance for some reason?!? Strangely enough, the set of bearings by the rear of the engine looks very good, and the rest are not too bad either. Any guess as to what is going on here?

Also, I feel like a ***** asking this, but I want to verify that from front to back (crank to flywheel sides) the rods are for cyls. 1-4-2-5-3-6

Thanks a bunch!

<small>[ January 24, 2004, 10:37 PM: Message edited by: Zap ]</small>

 

[sdpatt]

I'm not familiar with the markings you are referring to, but you do have the cylinder order correct. I had to look at a photo I took during my rod bearing service to get the order on the crank. The cylinder numbers are as shown.

Firewall
1-2-3
-------
4-5-6
Radiator

 

[Off Road SHO]

In the old days some factories would put in custom bearing if they found a journal or bearing surface a wee bit off. They would give it a different alpha character to signify each additional one thousandth of an inch.

Found this out the hard way on a Toyota motor.

Do you have access to a good quality vernier caliper that measures to 3 decimal places?

Tom

 

[Ishodu]

I see the markings your talking about but mine are D4L's. All 6 of them. You should get your crank measured like Tom has suggested and get some plastigauge (try a search on that).

 

[Zap]

From what I have found it appears that these bearings may just have lot numbers on them, or something to that effect. From the folks who have posted the identifying numbers in a few places, there are quite a few different ones between engines, and I find it hard to believe that non-standard sized bearings would be used on that many cars at that time. I know in the past that would have been normal, but from what I've read, that practice was pretty much gone when the SHO was made.

 

[Irish Pride]

Rod / Main bearing stamping part number

Yes, I know that this is a 21 year bump (record) but i've been researching this all day at work and wanted to document it some place.

The stampings on all the original/factory Ford rod and main bearings will start with a D and then have a number and then a letter. I have not pinpointed what the first D means but the number is the year and the last letter is the month of manufacture.

So to reference the first post in the thread, D4H would be August of 1994 and D4D would be April of 1994.

There should also be an ink number stamped on the bearing which represents the size of the bearing. #1 = standard. #2 = .25 oversized. Etc...

-Chad

 

[Toolman]

In the old days some factories would put in custom bearing if they found a journal or bearing surface a wee bit off. They would give it a different alpha character to signify each additional one thousandth of an inch.

Found this out the hard way on a Toyota motor.

Do you have access to a good quality vernier caliper that measures to 3 decimal places?

Tom

Just liked a +20-yr old post of Tom’s, he is missed.