Technical Tips

Have you ever wondered whether to buy a new car or invest money into your current car? Well with the economy being what it is today, you are better off investing in your old car. Unless of course the body is beyond repair or the frame is rotting away, you may want a new one or as they say today “A Pre-owned vehicle”. I am not a wealthy person so I opted to invest in my older vehicles. The main areas of concern are t he motor and the transmission. I decided to test there worth and this is how I did it.

Engine: I like physical tests instead of using a computer test.

Do a wet and a dry compression test

Do a cylinder leakage test

What we want to know is whether the engine is still in good condition and capable of sustaining a few more miles for a while. Ok, so what do these tests involve?

1. Compression testing (Wet and dry)

a. Using a compression tester to determine if the top compression ring is capable of holding enough pressure to fire the spark plug.

b. How do I do this? Disable the fuel system by removing the fuel injection fuse or non fuel injected engine remove the coil wire! Crank the engine over by the key 4 to 5 times and observe the compression gauge.

c. Compression should be 90 PSI or better (Most cars today can sustain anywhere from 120 to 160 PSI and be considered acceptable.

d. Now if the compression is lower than normal, administer a small quantity of engine oil or equivalent into the cylinder and repeat the test. If compression increases then there may be a problem with the compression ring or an engine problem!

2. Cylinder leakage testing (I like this test because it tests all of the piston rings at one time)!

a. Remove a spark plug or all if you want so that we can introduce a 100 psi pressure into the cylinder when the piston is at top dead center on the compression stroke both valves closed.

b. Bar the engine over to top dead center on the cylinder you want to test. Install the tester and calibrate the tester for the amount of pressure you want to introduce.

c. Cylinder pressure is read in percentage of leakage or how much pressure the cylinder will leak out over a period of time.

d. Acceptable leakage is about 0-25 percent. Good leakage is about 5-10 percent. Any more than 25 percent is unacceptable. There is always some leakage due to ring end gaps allowing air to leak by.

If air is escaping, it may be from one of 4 places.

1. The intake throttle body - bad or bent intake valves

2. The exhaust pipe - bad or bent exhaust valves

3. The dipstick shaft - Bad oil rings

4. The radiator inlet - possible bad head gasket

What this test tells me is that all the rings on the piston or intake and exhaust valves or head gaskets are at either acceptable condition or unacceptable condition. Now I know what condition the engine is in.

Transmission - This going to require a little more attention than normal. Because a transmission is a more complex system, you are better off leaving this to the professionals to look at. Transmissions take beating from there owners in some cases but the majority of transmissions out there can be saved with a little TLC (Tender Loving Care). Things like draining the fluid and inspecting the pan and some computer testing may be required to diagnose a problem. Replacing fluid and filters are a must to maintain longevity of the transmission. Good driving habits can also contribute to longer life span of the transmission. Checking for leaks and addressing them is very important. If the transmission runs dry of oil then the cost to repair it is going to be incredible when simple common sense tells us to be aware of these simple symptoms.

When your sitting around on the weekend, start you vehicle up and let it warm up and take it around the block, then when you get back,while it is still running in park with the emergency brake on, check the fluid level. if it is low add some or if it is Ok, then your peace of mind will be satisfied knowing all is well.

My theory is that I don't have 30,000 dollars or more for a new vehicle but if I spend 2 or 3 thousand over the same length of time it would cost me to pay off my car loan, I am a happy camper. Who knows maybe one day I will hit the lottery! :) LOL Yea Right!!!

When you get right down to it, What do you want to do? Deal with your current vehicle or buy a new one and maybe have to deal with it later. Can you say RECALL???

Check out the videos below!

Cylinder Leakage testing

Compression Testing

Checking transmission Fluid

Hey ya'll, I love watching those Automotive TV shows about muscle cars, where they put a new engine in the car. Then they try to start it and “Boom” it backfires and shoots flames out the carburetor. Now I don't know about you but this really pisses me off big time. These guys are professionals and can't get a car to start properly??? So with that being said I decided to start a Tech Tip Page, so that I can show you some short cuts on how to be more professional at your job!

TECH TIP NO. 1 -

Let's say your installing a new engine and your are about to start it for the first time. Something to make sure of is that the motor has been primed for oil pressure, (I will make a new Tech Tip for this procedure also). Ok, now lets assume (be careful of that word, we all know what that means) we want to get the motor started. Follow this procedure:

1. Remove No.1 spark plug
2. Get a breaker bar and a socket to fit the crankshaft bolt.
3. Start to bar the engine over and put you finger against the spark plug hole till you feel compression pushing against your finger.
4. At this point look at the damper pointer(make sure you mark the damper with paint or white out)
5. Look at the numbers on the damper and make sure that the “0” or zero is directly in line with the pointer!
6. At this point advance the damper to the recommended timing specification. (0 or 2 or 10 or what ever the manufacture recommends)
7. Now remove the distributor cap and see where the rotor is in respect to the No.1 spark plug wire .
8. If all looks well then re-install the distributor cap.
9. Now, re-install No. 1 spark plug.
10. At this point we are almost ready to start the engine.
11. Using a screw driver or a spark substitute, connect the spark plug wire to either one and turn on the key.
12. Rotate the distributor in the direction of rotation till the spark plug substitute fires a spark across it,
13. Lock the distributor in place till after the engine is fired and running for a while.
14. Re-install the spark plug wire.
15. The purpose of this is too get a preliminary timing point so the engine will start on the first key turn!
16. Once the engine is running, set timing to correct specification

I used to do this every time I built a new engine and never had to worry about backfire or destroying a power valve in the carburetor!

Good luck with this and be careful. If you mess it up, always have a fire extinguisher on hand to grab in case of an emergency!

AS ALWAYS SAFETY FIRST!!!

Automatic Transmission Fluid level Inspection

Natef Task - Check automatic transmission fluid level

Task 1 - Start the engine and bring it up to operating temperature  ___

Task 2 - Move the gear shift selector into forward and reverse gears ___

          Tip - This transmits the fluid to the correct places to assure an accurate                  level check! Make sure the engine is still running in park and set           parking           brake! Open hood. Install fender covers to protect from oil and scratches.

Task 3 - Remove the transmission dipstick and record the fluid level

                   Low______     High ______

Task 4- Record the condition of the fluid

                   Red and clean____  Burnt and brown____   Particles present____

Task 5 - install vehicle on lift___

Task 6 - Inspect transmission pan - Clean_____  Oil leaking _____

Task 7 - Record any other transmission visual problems, such as loose linkage or bolts. Wire connections! If leaks are present record the positions.

Problems_found_______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Task 8- Return vehicle to original condition and remove from lift! Make sure      to clean any grease or oil from vehicle exterior! _____

Task 9 - Record any safety precautions when performing this task and list              them below!

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________