Jim Smart
September 1, 2001
Photos By: Mustang Monthly Archives

Crack Check

Only a few of us get this one right until we experience the agony of an engine build gone bad. Check for cracks before the heavy expense of machine work. Locating the crack after machine work may save you the grief of engine failure, but it's still an expensive oversight that means redundancy and even more cash flow.

Blazing Saddles

The main bearing saddle alignment gets overlooked more than anything else during an engine rebuild. Have someone at the machine shop check the line bore before pressing ahead to any other machine work. And if necessary, have him bore and/or hone the main bearing saddles. This gives your crankshaft a comfortable spot in which to sit, which means less wear and tear on the main and rod bearings.

Clean Up!

It's easy to take for granted that the folks at the machine shop have performed a stellar clean-up job on your engine's block and heads. Oil and cooling passages must be clean. Make sure the oil passages are clear from stem to stern and the cooling passages are free of rust and iron particles. Look at the crud in the water jacket on this rebuild we witnessed in one Los Angeles machine shop! Examine your castings before the engine is assembled.

Keep Your Seat

Twenty years ago we were worried about the absence of lead in gasoline because lead served as a valve seat lubricant in the old days when iron cylinder heads had iron exhaust valve seats. The sky didn't fall after all, because unleaded fuels have served to clean up the air and our engines. Still, too few of us are installing hardened steel exhaust valve seats during our rebuilds to ensure longer cylinder head life. Don't forget to install hardened exhaust valve seats whenever the heads come off.

More Isn't Better

Too much silicone sealer can harm your engine. Why? When too much silicone sealer is used, it can block oil and cooling passages, thereby causing hot spots and definitely dry spots. Globs of loose silicone sealer follow a path to the radiator, thereby plugging the cooling tubes and causing overheating. Loose silicone can also find its way to the oil pan and end up plugging the intake screen and limiting oil flow. Just a dab will do. Use a thin film of sealer on just one side of a gasket surface, then install the part. Use silicone only at cooling passages and in areas where oil may leak. Intake ports don't need it.


You wouldn't believe the number of engines that get assembled with the main and/or rod bearings installed backward. Nagley told us, "Check for the bearing tab's location during installation. There shouldn't be any oil between the bearing and the saddle or rod. Seat the bearing snugly, and make sure the oil holes are aligned correctly. Cam bearings are especially easy to install incorrectly. Check the oil holes for correct alignment in all applications."

Lube The Lobes

All camshafts should be lubricated during installation. Only a few of us get this one right. Flat-tappet camshafts need lots of lubrication, then a good, 20-minute warm-up at 2,500 rpm, according to Crane Cams. Roller tappet camshafts don't need the warm-up lap, but they do need lubrication. Make sure all journals and lobes are covered with assembly lube before fire-up.

Getting It Right For 1967

Did you know that 1967 was an odd-duck year for Mustang V-8 engine mounts? Before mid-1966, Mustangs had doughnut-style V-8 engine mounts. In mid-1966 Ford redesigned the Mustang V-8 engine mount to create a saddle affair, which allows the engine to sit lower and the mounts to take up more vibration. It may surprise you to know that the '67 Mustang V-8 engine mount stands alone from the '66 and the '68-'70, because-dimensionally-it's a different mount. How do we know this? From hours of fighting with a duo of aftermarket engine mounts our auto parts store said would fit on a '66-'70 Mustang or Cougar.

When we visited with Cecil Myers at Mustangs Etc. in Van Nuys, California, he told us the '67 Mustang and Cougar stand alone when it comes to small-block engine mounts. For the '67, the 289 gets two D0ZZ-6038-B mounts where the holes are positioned 11/44-inch differently from the '66 and the '68-'70. What's more, the mount and the bracket are geometrically different. Apparently, Ford engineered new dimensions for 1967, then had a change of heart back to the '66 dimension for 1968. If you have either a '66 or a '68-'70 Mustang, aftermarket mounts will fit just fine. If you have a '67, you'll have to opt for D0ZZ-6038-B mounts, which currently retail for approximately $100 each. One way to get out of this is to install '68 Mustang engine mount brackets in your '67 and use '66 or '68-'70 mounts. Just don't forget that's what you did later on.