Performance Notes, Inspiration Leads To Innovation For Resurfacing Tool - Engine Builder Magazine

Performance Notes, Inspiration Leads To Innovation For Resurfacing Tool

All too often we start with a good rebuildable engine core only to find the camshaft thrust surface has taken a beating at some time in its previous life.

This is not a new problem for engine builders. Machinists have come up with a number of solutions to these problems throughout the years. Some of those methods of repairing worn thrust surfaces may work for you and your shop, but most require lifting the block in and out of the milling machine and quite a bit of set up time.

We build a simple tool to make repairing the camshaft thrust surfaces easy, and most importantly – profitable (about ten minutes start to finish). Our tool is called a “Camshaft Thrust Resurfacing Tool” and it fits into the camshaft tunnel of the engine block. We feel 99 percent of all automotive machine shops already have valve seat grinding equipment with various stones and pilots; the Camshaft Thrust Resurfacing Tool allows you to use your .375″ valve guide pilot,

valve seat stone holder and stones to regrind the worn camshaft thrust surface. The cam bearings must be removed before the Camshaft Thrust Resurfacing Tool can be inserted into the block.
After the tool has been inserted into the block a .375″ pilot is inserted into the tool (see Photo 1 and 2).

Photo 1 & 2

You will need a 3-inch general-purpose flat stone to be able to resurface both small and big block engines. Carefully dress the stone flat by setting the diamond at 0°. Now dress the outside diameter of the stone with the stone dresser set at 0°. The large stone will run much more smoothly after both surfaces are dressed (see Photo 3).

Grind the thrust surface for a few seconds and check your work. The thrust area may only need a light touch up to create a desirable, oil retaining, new thrust surface (see Photo 4). If the block is worn badly then more grinding is required and an after market thrust washer will be required between the cam gear and the block (see thrust washer – Photo 7).

The next step we do is to check the fit of the camshaft thrust washer on the engine using a straight edge (see photo 5). The camshaft thrust surface is the same height as the timing cover surface. Place the straight edge across the timing cover surface and grind the thrust surface until the thrust washer just fits between the straight edge and the block (see Photo 4).

Photos 3 through 7

After grinding recheck the surface using the small straight edge placed across the adjacent block surface to determine when enough metal has been removed. Again the thrust washer should just fit under the straight edge (see Photo 4 and 5).

We are careful to keep the camshaft in its original position in the block. That is why we keep checking with the straight edge as we grind. The lobes on a camshaft are tapered slightly. If a camshaft is too deep into a block the lifters will rotate too fast and cause problems. If the cam is not deep enough the lifters will not rotate at all and will scuff and wear quickly (Photo 5).

We have used the Camshaft Thrust Resurfacing Tool on many blocks since we invented the tool. We have noticed that if a block has a great deal of core shift the tool may not enter the camshaft tunnel because the lifter bosses are down in the tunnel. Blocks with that much core shift may not be a good choice for rebuilding and the tool kind of lets you know this.

We have developed this tool for both small block and big block Chevys. The blue anodized tool (see Photo 6) is for the small block engines. The natural aluminum anodized tool is for the big block engines.

Our frustration with existing repair methods led to our inspiration to create this tool for our own use. But we also want to make it available to other shops that suffer the same challenges. It’s been extremely helpful to us and will most likely be helpful to you as well.

You certainly have ideas in your own shop that can be turned into tools that others would be interested in as well. Talk to your shop supplies representative to find out how to develop and market such a product. Not only will you be helping an industry, by selling the tools you’ll be helping yourself, too.

Jerry & David McLain operate McLain Automotive in Cuba, MO. For more information about the Camshaft Thrust Surface Repair Tool, visit them online at

You May Also Like

America’s Best Engine Shops 2022 | Choate Engineering Performance

This shop’s dedication to quality engine work, its growth, its machining capabilities and its impact in the diesel industry, all make Choate Engineering Performance well deserving of Engine Builder’s and Autolite’s 2022 America’s Best Diesel Engine Shop award.

Necessity is the mother of all invention, and it certainly played a role in the founding of Choate Engineering Performance. The diesel engine and machine shop was founded by shop owner, Cass Choate, after finally becoming fed up with having to rely on others for certain aspects of his work.

America’s Best Engine Shops 2022 | 4 Piston Racing

The 4 Piston Racing facility in Danville, IN houses two buildings – one is 12,000 sq.-ft. and the other is 2,500 sq.-ft. The shop is very heavily focused on Honda cylinder heads and engine work to the tune of 300+ engines and 1,000 cylinder heads annually!

Randy Bauer Shares His Experience as PERA President

We recently spoke to Randy about his PERA presidency and what some of the biggest hurdles are facing the engine remanufacturing industry right now.

Women in Motorsports: Mattie Graves

Mattie Graves competes in the Outlaw Diesel Super Series (ODSS) dragster class, and is the only female doing so in a class that already has very few competitors in general. Find out more about this up and coming diesel drag racing star.

Women in Motorsports: Johnna Dunn

She got her drag racing license before she got her regular license, and that tells you everything you need to know about Johnna Dunn. She’s a drag racer and clutch specialist for her grandfather’s NHRA Top Fuel Funny Car team, Jim Dunn Racing.

Other Posts

Women in Motorsports: Kayla Blood

A veteran of the military, a former track star, an MMA fighter, Motocross and ATV racer, and now a Monster Jam driver, Kayla Blood has packed a lot into her still growing career. Now the driver of Soldier Fortune, she strives to make a name for herself and for other women looking to make motorsports a career.

Women in Motorsports: Felicia Smith

Felicia Smith was never a huge gear head. However, following her first taste of speed at the track, she’s been living a life of cars and racing ever since. She’s taken the past six years to build up her CTS-V and her own car/engine skills in an effort to share it all with the car community.

Women in Motorsports: Jillian McLaughlin

Not all of us start out in this industry. Take Jillian McLaughlin for example. The once hairdresser is now an engine builder helping do a little bit of everything at Precision Machine Engine in California.

Women in Motorsports: Janine Shoffner

Whether it’s motorcycles, skydiving or road racing, Janine Shoffner has an addiction to adrenaline-filled activities. For the last decade, road racing has been her biggest passion as a co-founder of J2-Racing.