PER Notebook

In my last article I talked about doing a complete rebuild to your engine. Your engine may be badly damaged and you have decided you don't want to tackle a complete rebuild or it is to costly. You have checked into a new engine and found it may not be available or need costly modifications for your application. Considering a shortblock as an option may prove to be the only way out to get the equipment in like new shape again and insure that you don't have to modify equipment. A shortblock may also prove to be very economical compared to other options if you can do the labor yourself. A shortblock normally contains a 90 day new parts warranty from the engine manufacturer covering defective material or workmanship, the same warranty that applies to any new part.

A new shortblock normally consists of all the internal engine parts, including the crankshaft, piston, rod, camshaft, valves and governor, but normally not the cylinder head and sometimes not the oil pan. If the shortblock is for an OHV engine, you will need to address any valve problems when transferring the head. All gaskets and seals needed to do the job are included. The beauty of a shortblock is you don't have to worry about internal parts and only need to install the external parts such as cylinder head, carburetor, linkages, magneto, flywheel, starter and shrouding. If you are considering a shortblock, here's a list of things to evaluate first, before doing your installation:

When considering a shortblock keep in mind that just replacing the shortblock may not put the engine in first class shape. You will also need to do such things as rebuild the carburetor and replace all filters and fuel line hose. New Briggs & Stratton shortblocks are designed for magnetron ignition and do not have a plunger hole for the points, so you may have to convert the ignition system to a magnetron if your engine was built prior to 1983.

As with other repair procedures I always recommend purchasing a repair manual for your engine to help you make the proper torques and adjustment procedures for the governor and carburetor etc. You may also want to consider a flywheel puller to make that part of the job easier. If you own a digital camera, take pictures of the governor springs, linkages and other items you may want to look at when it comes time to install these items. Since you will not have to worry about the engine internal parts, you should clean and set the components aside in groups to be assembled in a logical order. Clean up the cylinder area and apply a teaspoon of oil around the upper cylinder before putting the head on. Here's a sequence I normally follow on an L-head engine:

One final note: The most important procedure you will do when installing a shortblock is adjusting the governor and linkages. Click here to view additional information on this. Make sure this is done along with filling the crankcase with the proper engine oil, before attempting a startup. You now have an engine that is in everyway as good as a new one and should give you just as many hours of service if you were careful in both your evaluation and repair. Now pull the rope or turn the key and enjoy your new/old engine with the satisfaction that you made this fine piece of machinery - Bruce Perrault