November 2022 Shop Solutions - Engine Builder Magazine

November 2022 Shop Solutions

November tricks and tips for the shop!


Chasing threads at the bottom of deep holes in engine blocks can be done with a pulley tap. Pulley taps are made with an extra-long shank. However, if you do not have a pulley tap, you can make a tap extension.                                                                                                                           Here’s how: Cut off the threaded end of a long bolt and drill a hole in the end of the bolt’s shank 1/2” deep. To determine the hole size, measure the distance across the flats (AF) of the tap’s square drive.

Multiply AF distance by 1.155 to find drill diameter (DD). Example: AF = 0.252” Drill size = 0.252” x 1.155 = 0.2916”. In this case, use a letter “L” size drill bit (0.290”). Set the tap’s square drive on the hole in the bolt; mark the bolt where each corner of the tap’s square is located. Using an angle grinder with a 1/16” wide cutting wheel, slot the bolt where marked, about 1/2” length. Slots should be just wide enough to let the tap’s square drive wedge into the bolt’s hole. 

Slot width is typically 0.196 x DD. Max slot width = 0.392 x DD. Example: typical 0.196 x 0.290 = ~0.057” and Max 0.392 x 0.290” = 0.114”. If you wish to permanently secure the tap, silver solder it in bolt. Otherwise use the tap with the wedge fit, or with cured red threadlocker.

Tom Nichols, Automotive Machine & Supply, Joshua, TX


If you are rebuilding Ford V8 marine engines from the ‘80s and ‘90s, the marine reverse rotation 1-piece rear main seals can be expensive and almost impossible to find. The late model PTFE rear seals are non-directional and make a great seal to use in these applications. The PTFE option will work great on your late model GM marine engines as well. Always follow the manufacturer’s installation instructions.

Dave Sutton, Sterling Engine Parts, Minneapolis, MN


When rebuilding vintage engines, a person must deal with rusty components. When I have rust pits in the cylinders that do not require sleeving, I treat them with rust dissolver jelly right before honing. It may take a few times to get it and a small stainless brush helps. I believe it stops the rust and oil spots right after final washing. I’ve had engines on the stand for many days and even weeks without the pits growing or showing rust – in my experience anyway.

Randy Torvinen, Torvinen’s Machine, Menahga, MN


When port matching intake manifolds, I make some different shaped “Reverse Scribes” to get in and scribe mark the dye on the intake manifold flange side. It works great, is often easier than marking and transferring an intake gasket pattern, as this gives you a real time indication of where to port to. Sometimes transferring a gasket can allow for some misalignment if you’re not 100% right on. 

Ron Flood, Cedar machine, North Branch, MN

You May Also Like

Shop Solutions July 2023

Engine and machine shop tips and tricks.


To precisely shorten bolts in the lathe, I made slotted collets for each bolt diameter. They are fractional in length to measure off the end, so you know where to cut for your length. I’ve used large O.D. valve guides and aluminum round stock. Just make the collet big enough to clear the bolt flange, hex or socket head.

Shop Solutions June 2023

Engine and machine shop tips and tricks.

May Shop Solutions 2023

Engine and machine shop tips and tricks.

April Shop Solutions 2023

Engine and machine shop tips and tricks.

Shop Solutions March 2023

If I’m not using torque plates, I tape up both sides and trim out the bores. I use painter’s tape, which comes off easily and doesn’t leave any glue residue. I get much less oil in the spray washer this way.

Other Posts

Shop Solutions February 2023

Check out February’s shop tips and tricks.

Shop Solutions January 2023

Next time you have set of large journal small block Chevy connecting rods to resize, consider honing the big ends of them for a +.002” outside diameter bearing that the LS engines with fracture cap rods use.

Shop Solutions December 2022

Everyone misses occasionally, and this helps avoid dents and damage.

Shop Solutions October 2022

When machining on the CNC mill, it’s necessary to blow the flood coolant and chips off the parts for inspection. I tried a tool holder mounted fan, but it wouldn’t get all the chips and coolant out of the deeper areas.