OK...I have been chasing an oil pressure ghost for a while now...I have the crank back out and I noticed on the parts list that there is a part 8BA-6307, which is a plug that goes in the end of the crankshaft. I have heard it called an oil plug, sludge trap plug and weight plug. DOES ANYONE KNOW WHAT THE HELL THIS THING IS?? I have searched and been unsuccessful at finding any information on it. Any information is helpful, especially pictures. I was able to research this plug on newer engines, and it seems that it is very important to the oil pressure barrier. I don't think this crank has one in it...and I am very confused. HELP!!

 

i'll keep your post at the top. wait for the experts to confirm. i think their are four plugs. the originals, i think, are just fairly thick press-in plugs. we used a slide hammer with a screw threaded point to yank them out. i think you can find the original type replacements, but some builders tap out the hole with pipe thread and put it a pipe plug. when you have them out, you want to clean out the passage ways in the crank.

 

Dick's got it right, they are in the crank throws, there are 4.
Crankshaft Plugs - 3/8 [168] - $5.00 : Red's Headers, Speed Equipment For Old Fords

If you were missing even one, you would have very very low pressure.

 

Scroll down to 8BA-6307 // GREEN SALES CO. in Cincinnati OH has 225 = 800-543-4959.

 

Does anyone have a picture of the original plug? Maybe in the hole? I want to be sure that mine are actually missing. I don't think they are there, but I have nothing to compare it to.

 

the link ross gave you was to pictures of the orig style plugs from red's headers. they are bullet shaped but hollow tap in plugs. the picture is of the recessed head pipe plug style. if you have the crank out and are concerned about oiling, you may want to pull them anyway and clean the sludge out. check the size, i vaguely remember something about 3/8" ford 5/8" merc. help me out here guys.

 

Do they make cranks without these holes? It appears that the crank that came out of it didn't have any...I am puzzled...

 

No, they all had them. Maybe filled with junk? The original style press-in's have thick walls, so the opening you can see is pretty small, like 1/8" or so.

Dick, those numbers sound right to me. But not all Mercs had the bigger plugs, not a reliable way to discern a Merc crank at any rate.

The screw-in type are to be avoided at all costs, IMO. Here's what it took one guy to get his out. As I recall it took him several days...

Can you post a picture of your crank throws?

I think the plugs you may have originally been talking about are the ones at the front and rear of the block, at the ends of the oil distribution tube down the valve chest. You can pull off the timing cover to see the front one, and the rear one is under the oil pump drive gear cover at the rear of the block. As I recall, one of them is real hard to see without pulling the gear out (pretty sure it's the rear one).

 

i see only one that i have a driver for.. the others must be special order one"s
lol

 

Actually yes, but not during the 8BA engine years. All the earlier Ford flathead V8s came with floating rod bearings and did not have the clean out plugs. If your crank only has one oil hole per rod journal, you have an earlier crank and you must use the earlier floating rod bearings and rods.

 

Well...*****! It looks like I have the crank out of an older engine...and yep...you guessed it...non-floating bearings/rods. I bought it on ebay from RPM Motorsports and it was listed as an 8BA crankshaft. It bolted right up, so I didn't even think twice about it. I only ran the truck for a few minutes, and didn't like the oil pressure. I was only getting about 5# at a hot idle, which I know isn't bad, but for a newly rebuilt engine, I thought it was low. Sure enough, I looked at the throw, and it only has one oil hole. Now I have to find another crank, and pull the engine again. Maybe I will get lucky and find one with STD journals...HA! That means I will probably need new bearings too...I guess we learn as we go...

 

I'd ask for your money back from RPM, and then some!

I thought the rear seals were different enough on those early cranks that it wouldn't bolt up without some rework, same on the timing end. On the bright side, if the crank is still good, there may be some guys on the Ford Barn who are interested in it, if RPM stiffs you.

 

I should have known better when I had to swap out the front timing gear. Someone mentioned that it might be off an earlier engine, but I didn't think it would bolt up if it were that different. The only difference is the oil holes. Other than that, it bolted right up. I bought the crank last July, so RPM has every right to tell me to take a hike, but they usually make it right. I emailed them, so we will see.