Newly Installed Engines: Critical Care for the First Few Weeks

Whether you install the engine yourself in your Mitsubishi Fuso FE, FH, FK or UD 1200, 1300, 1400, 1800 or 2000 series, Isuzu NPR, NQR, GMC W3500, 4500, 5500, any other mid size truck or even regular passenger cars or whether you hire a mechanic or if the dealership installs an engine in a truck, the first couple weeks are critical in the life of that engine.

Let me tell you why: any time a new or used engine is installed in a vehicle, many fittings, many bolts have to be loosened, many hoses have to be taken apart, many connections, electrical – oil – and coolant lines and fittings have to be disconnected. There is always a risk –no matter who does it whether its owner operated or a dealership — there is always the risk of one of these fittings leaking, and causing severe damage to your newly installed engine.

Here is one way of ensuring that you don’t have a leak or a problem.  Every day for the first week, check all the fluid levels – coolant, oil, transmission – before you crank up first thing for the day. Then midday, check them again. Check the truck’s fluid levels every 3-4 hours on the first couple days you run the truck.  Take note of where the levels are.  Word of caution: DO NOT OPEN THE RADIATOR WHEN IT’S HOT, only check it when it’s cooled off.  You run the risk of getting serious burns if you open a hot radiator.

Here is another way to watch for a leak.  Each night, when the truck is sitting, slide a clean piece of cardboard underneath your truck. The next morning, take note if there are any drips on the cardboard and what color the fluid is – green or red antifreeze, black oil, red transmission fluid – and where they are located so you would have some idea as to what is leaking.  Drips can result from a loose clamp, or maybe a fitting or bolt that is not tightened, it can be something very simple but it can also be something that turns into something major.

The cardboard under the truck is a great way to check for leaks. I would do this for at least the first 7 days. Thereafter, each day check your fluid levels in the morning when the truck is cold. It’s always a good idea to check your fluid levels every morning for the life of the truck if you run it all day long, every day. This will ensure that you catch a fluid problem before it causes you severe damage.

Most used engines will come with heat tabs that are installed before installation. If the engine is run hot and exceeds the engine’s heat limits, these heat tabs will melt.  If they are melted, it voids any warranty that the owner of the vehicle will have against the engine provider.  So it is critical to keep the coolant and oil levels of these trucks up to the proper levels.


Inform Your Driver an Engine has Just Been Installed

Caution the driver to watch the gages and lights carefully.  After installing an engine,  alert your driver that there is a newly installed engine, making him extra aware of the gages.  Also make sure your gages and caution lights are working properly. Caution him that if a light comes on — temp or oil – stop the truck immediately, do not wait because the engine can be ruined in less than a minute with no oil. One minute with no oil pressure can ruin the engine. He needs to get off the side of the road, out of danger, and stop it as quickly as possible.  Do not try to make it to the next exit with the oil light on.

Caution the driver to listen carefully for any unusual noises.  During that first week of installation, it is important for the driver to use his ears. Any noises that are out of the ordinary, he needs to be aware of them. If he hears a knocking, a whining, or anything out of the ordinary that is different, take note of it.  Belts can be loose, pulleys can lock up, unusual noises in the engine are just like symptoms for a sick person… signs that something is wrong. Unusual noises don’ t just happen by chance and go away. When unusual noises come about there is a cause.

Drivers need to be made aware to listen intensely for unusual noises and watch the lights and gages for at least the first week.

After your first 2-3 weeks of service with a newly installed engine — after the first 1000 miles — I would recommend that you change your oil and filter to ensure that any contaminants which might have been shaken loose in the installation of the engine are removed from the crank case of the engine. Also take note when you pull the oil plug for any excess metal that may have attached itself to the magnetic oil plug. Some very small shavings are to be expected, but any chunks larger than a pencil eraser may be an indication that there is a problem.

Time spent watching for problems will keep your cost on repairs down as well as the down time it costs to be without the truck.

So here’s the bottom line:   When you install a new engine in your truck, be aware of anything out of the ordinary. Make your driver aware that there is a new engine, and that he should be aware of anything unusual. A little bit of awareness can save you thousands and thousands of dollars.


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