If you’re looking to make a change with your automobile engine, deciding whether you should pay to have your current engine rebuilt or pay for a brand new engine can be extremely difficult. Making things even tougher is the fact that the average cost of rebuilding any engine is dependent on many different, fluid factors like the level of maintenance your current engine needs and the varying costs from one expert and laborer to another.
When rebuilding a stock engine for transportation purposes only, the cost should not exceed 50% of the cost to purchase a new one. This is a good rule of thumb if you really are only considering engine replacement for transportation and nothing else.
However, when rebuilding an engine for performance this rule of thumb does not apply and the price difference between a hypothetical rebuild and a hypothetical purchase can become razor thin and very blurred. Rebuilding an engine includes hiring the services of a machinist and a mechanic, unless you find a mechanic with all the tools and knowledge of a machinist.
Machinist vs. Mechanic
A mechanic is someone who replaces parts using tools whereas a machinist makes parts using a machine. A thorough engine rebuild requires the expertise and service of both. This is not a short order considering most machinists and mechanics specialize in their respective fields, and employing two totally different people to play such crucial roles with one single engine build is costly and could be disastrous.
Ideally, you need to find a great mechanic who already has a trusted, working relationship with his own great machinist.
Machinist Role and Cost
Consider all the parts that can be reused. Typically, a machinist will clean everything from the engine block to the connecting rods. The machinist will also usually be responsible for boring the block, and milling the cylinder heads, along with installing bearings, plugs, piston pins as well as installing the pistons onto the piston rods. A machinist has the tools and knows how to turn the crank under, precision to within .001 inch is necessary to ensure consistency for a proper fit, or else you’ll be replacing the engine again and much sooner than you think.
A machinist can determine and oftentimes repair areas of the engine a mechanic will not even see. If only cleaning is required the cost will range from $350 to $600, however, if the machinist finds any problem areas that need repair or replacement the price will go up.
Unless you can remove and replace all the parts yourself, you will need a qualified mechanic. It is advisable to locate a mechanic who is familiar with your make and model of vehicle. You don’t want a Mercedes specialist working on your Ford Mustang. The mechanic knows where all the parts go, how and where to lubricate the parts, adjust the valves, set the torque, adjust the timing, check pressures, along with the experience to hear any problems. The engine is a precision machine and requires all parts to operate optimally. Mechanics charge by the hour, a basic rebuild with no problem parts will run approximately $1,200 to $2,000.
One benefit of a rebuild is that, thanks to the quality and longevity of modern car engines, complete engine replacement is not really a necessity.
A rebuild kit may provide more updated parts than your current engine. The costs are generally within a competitive range of a rebuild and far less expensive than replacement. A kit should include plugs, seals, rings, oil pumps, etc. They do not include belts, water pumps, alternators etc. A rebuild kit will run from $450 to $3,000 depending on the vehicle and its performance requirement.
Again, this is a difficult decision and not one to take lightly, regardless of which option you choose. If you want the best possible results at every stage, you could be paying thousands for it.