How to Inspect and Prep a JDM Engine - Project Car Magazine

How to Inspect and Prep a JDM Engine - Project Car Magazine   |   How to Inspect and Prep a JDM Engine

The days of finding a 30,000 mile used JDM engine like an SR20DET, 4AGE or B16 are almost over. Ten years ago, almost everything being imported was clean and the importers simply scrapped anything looking questionable. As the Japanese economy spiraled downward, so did the supply of good engines. Japanese car owners were forced to hold onto their cars longer, often without keeping up with maintenance. More importantly, many of these engines have now been in cars for 15 to 20 years. Finding a 90’s model car with 30K on the clock is quite difficult anywhere in the world. So, in today’s market, a little knowledge can go a long way when selecting the right engine for your swap.

For starters, ask around to find a reputable seller-preferably someone local to you. By dealing with a local seller, you can hand pick an engine and in many cases have them do a compression or leak-down test right in front of you. Even if you have to pay a little more up front, it’s best to be able to see what you’re spending your hard earned money on. If you must have it shipped to you blindly, finding a reputable seller is key, but be sure to clarify what their return policy before dropping any money. Equally important is to make sure that the engine is complete. Do your research well in advance so you know exactly what components will be needed for the swap. In many cases, you’ll need the JDM harness, ECU, MAF and igniter, while in others you can get away with a bare long block.

When picking up an engine for Project Black Flag, we had to go through the same selection process as many of you have experienced or will experience in the near future. Luckily, we had some expert help from Marco Vargas of the SR20 Store who’s been dealing with SR20s for over a decade. As always, we had our cameras ready to bring you the insider tips. While we would have purchased our engine from the SR20 Store, they didn’t have one available. Instead, Marco referred us to M&P Trade Inc. located in Compton, CA. These guys were extremely helpful and had just what we were looking for at a price we could afford. For step-by-step information about the FWD SR20DET engine swap please see our last issue of Project Car (issue # 8).

TOOLS NEEDED: Engine hoist, engine stand, ratchet, metric sockets a combination wrenches, Phillips and flat-blade screwdriver, hammer.

Engine Inspection

How to Inspect and Prep a JDM Engine - Project Car Magazine   |   How to Inspect and Prep a JDM Engine

01 If you remember one thing, make sure it’s this. Remove the oil filler cap and look inside. This usually requires a flashlight so be sure to bring one with you. If it looks nice and shiny inside, it’s probably a really good engine. A brownish color on the inside is to be expected on a higher mileage engine. If you see black walls and a lot of carbon build-up, put your money back in your pocket and keep searching.

Also be sure to check the cam lobe for wear (see following steps). Once you’ve found something worth bringing home, ask the seller if they’ll do a compression or leak-down test for you. If they’re willing to do it, it’s worth your time to get it done. However, be aware that the results may not always be accurate if the engine’s been sitting around for a long time. Quite often, a valve or two might stick from the months/years that it takes to get from the overseas donor car to engine supplier you’re dealing with. We’ve seen many engines that initially tested low come back and test perfectly after running for a few minutes. When doing a compression test, look at the spark plugs as well. If there’s a major problem on a particular cylinder, often you’ll see signs of it on the corresponding plug.

How to Inspect and Prep a JDM Engine - Project Car Magazine   |   02 Once we got our engine back home, we pulled the valve cover for a closer inspection of the valvetrain. Note the nice clean shiny walls. Don’t judge an engine by its valvecover; it’s what’s inside that counts.
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine

Maintenance Prep

How to Inspect and Prep a JDM Engine - Project Car Magazine   |   How to Inspect and Prep a JDM Engine

09 When prepping an engine for installation, it’s recommended to change out the basic maintenance parts such as the water pump, front and rear main seals, thermostat and timing belt (when applicable). Dealing with these maintenance parts while the engine is out of the car will save you a lot of time and headaches later on. We sourced our parts from Superior Nissan in Puente Hills CA. Just contact Mike in the parts department; he usually keeps these parts on the shelf.

  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine
  • How to Inspect and Prep a JDM Engine - Project Car Magazine