Best way to remove Crankshft Plugs

Pete from OZ

Pete from OZ

Member
Hi Fellas,
This is my first Flat Head build ( 8BA ) and I would like to know the best way to remove the 4 plugs from the Crankshaft to clean out the Oil passage,

They are a Slotted type. I have tried my Impact Screw Driver. But no good.
I also have to remove the Oil Gallery plug in the front of the Block. Same slotted type.

Any help would be much appreciated.
Thanks,
Pete from OZ.
 
The originals are a freeze plug type press in, 8BA is 3/8"... You may have plugs that have been owner improvised. Some people -including me sometimes- have a tendency to over tighten things.

The plug in the front of the block should be 1/8" pipe and I suspect that your crank plugs could be the same 1/8" pipe thread. I think that I would try heat on the area around the front of the block. Drilling the plug may be an option, be careful if using an easy-out, they can break. I use a round ended chisel arrangement to pick out the pieces, or collapse the remnants of the plug.

Karl
 
For the plug in the front of the block I used a screwdriver that was a good fit in the slot and had a square shank. Used a wrench on the square shank while pressing firmly on the screwdriver to hold it in the slot.
 
Hi Karl,
I believe you are right with the 1/8 Pie Threads in the Crankshaft. I will try the Heat around the plug method and see how I go.
The 8BA appears to have never been apart till now. Standard bore and bearings.

Thanks 40cpe. I think I will also have to heat around the plug.
Thanks Flatjack9. Heat it will be

Pete from OZ
 
I believe the original plugs were 3/8 press in plugs. Some guys remove them to clean the oil passages and then tap them to hold a screw in plug. Mercury cranks have 1/2" press in plugs so if you cannot unscrew the current plugs you could drill them out to take the Mercury press in plugs. JMO
John
 
Most of the cranks we get here in the USA have press in plugs, every once in awhile I'll get Canada crank with 1/8 pipe plugs. The best way to get them out is stand the crank on end, heat the plug with a torch, with the plug pretty hot melt some wax around the plug, use a good screw driver that fits the slot, you can almost screw it out by hand or use a wrench on the screw driver, there come right out easy. Walt
 
Hey Walt,
You nailed it. Canadian Flathead with 1/8 Pipe Plugs in Crank.
I went with Karl Wolf,s suggestion and they came right out with a little heating around the Plug.
Boy there sure was a build up of Gunk in the Crank oil passages.
No luck with the Brass Oil Passage Plug. I Drilled it out as near to the Thread as possible, and used a small screwdriver and hammer to get the rest out.
Removed all bearings and bushes from the Block, and next week it is off to Redi-Strip.
Thanks all for your advice.
Pete from OZ
 
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At our shop we remove the plugs prior to tanking the crank so all gunk and other material is removed before putting it in our crank grinder. We replace them by threading the holes and installing Allen head plugs with sealer to prevent oil leakage. Any changing of the crank assembly requires that it be checked for balance.
 
Hi Pete,

If this is your first engine build you will be pleasantly surprised at how clean that block will come back from Redistrip. Good luck with the rebuild
 
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