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you DON"T have to start and run an engine to prepare for a compression test...

do it cold..  

COMPRESSION TEST




A noticeable lack of engine power, excessive oil consumption and/or poor fuel mileage measured over an extended period are all indicators of internal engine wear. Worn piston rings, scored or worn cylinder bores, blown head gaskets, sticking or burnt valves, and worn valve seats are all possible culprits. A check of each cylinder's compression will help locate the problem.

A screw-in type compression gauge is more accurate than the type you simply hold against the spark plug hole.

Although it takes slightly longer to use, it's worth the effort to obtain a more accurate reading.

Make sure that the proper amount and viscosity of engine oil is in the crankcase, then ensure the battery is fully charged.
Warm-up the engine to normal operating temperature, then shut the engine OFF .
Disable the ignition system.
Label and disconnect all of the spark plug wires from the plugs.
Thoroughly clean the cylinder head area around the spark plug ports, then remove the spark plugs.
Set the throttle plate to the fully open (wide-open throttle) position. You can block the accelerator linkage open for this, or you can have an assistant fully depress the accelerator pedal.






Install a screw-in type compression gauge into the No. 1 spark plug hole until the fitting is snug.


WARNING
Be careful not to crossthread the spark plug hole.

According to the tool manufacturer's instructions, connect a remote starting switch to the starting circuit.
With the ignition switch in the OFF position, use the remote starting switch to crank the engine through at least five compression strokes (approximately 5 seconds of cranking) and record the highest reading on the gauge.
Repeat the test on each cylinder, cranking the engine approximately the same number of compression strokes and/or time as the first.
Compare the highest readings from each cylinder to that of the others. The indicated compression pressures are considered within specifications if the lowest reading cylinder is within 75 percent of the pressure recorded for the highest reading cylinder. For example, if your highest reading cylinder pressure was 150 psi (1034 kPa), then 75 percent of that would be 113 psi (779 kPa). So the lowest reading cylinder should be no less than 113 psi (779 kPa).
If a cylinder exhibits an unusually low compression reading, pour a tablespoon of clean engine oil into the cylinder through the spark plug hole and repeat the compression test. If the compression rises after adding oil, it means that the cylinder's piston rings and/or cylinder bore are damaged or worn. If the pressure remains low, the valves may not be seating properly (a valve job is needed), or the head gasket may be blown near that cylinder. If compression in any two adjacent cylinders is low, and if the addition of oil doesn't help raise compression, there is leakage past the head gasket. Oil and coolant in the combustion chamber, combined with blue or constant white smoke from the tail pipe, are symptoms of this problem. However, don't be alarmed by the normal white smoke emitted from the tail pipe during engine warm-up or from cold weather driving. There may be evidence of water droplets on the engine dipstick and/or oil droplets in the cooling system if a head gasket is blown.  

here is some cooling system info




 

trying to find in my Haynes manual how to do a proper radiator pressure test for my car but not finding it. Want to make sure i do it by the book .  

engine OFF      pump it to 7 PSI... stop......    check for leaks...   watch to see how long it takes for it to leak down.. should hold pressure for along time...  more than 10 minutes..

and yes.. the cooling system cap says 13PSI  or .9 bar    but all caps are coolant recovery caps.. and usually release at about 7 to 9 psi.. its been a LONG time since i had the cap adaptor out of the bottom drawer of my tool box.. i just use my pressure tester and most of the time replace the cap if it even looks bad..

i have had too many instances of the cap not holding pressure and causing an overheat that blew the head gasket..

oh... and overpressurizing the system above about 7 pounds.. is hard on the hose fibers...  you want to check for leaks... NOT create new ones to happen after testing..

DO NOT run the engine with the radiator pressure tester pumped up without your eyes on the gauge.. .. and i know you have your valve cover off.. this is for knowledge...  as coolant expands..  the pressure will rise as the tester does not automaticly control pressure...  it can exceed the test pressure in just a few minutes and blow a hose or the end of the radiator tank off.. or worse.. blow the heater core open.  

Thanks man. I'm going outside right now to pressure test it. I'll stick with 7psi. My cap actually says 16lbs.  

I ran into a snag. The Radiator top is to small for the Radiator tester to fit on. Most radiator tops are bigger but this one in my 1995 ford escort is alot smaller then normal Radiator tops. The compression test comes with a blue tube things that allows me to hook up my smaller cap to, to pressure test the Radiator cap but not so i can hook it up to my Radiator. What part do i need so i can hook up the radiator pressure tester to my smaller radiator top??  

you need a radiator filler neck adaptor for the small filler necks..





OEM/Import Radiator Adaptor


Part Number: 27112

should also be in the loan a tool section behind the counter...  

transmission cooler quick connect ...



these are usually what i use... the smaller one sometimes comes with a new radiator..



this is the set one normally ends up with..



there are some X shaped versions... and some single sized aluminum versions for just over 20 bucks for a set of 4 or 5..  that i have also used..   the plastic ones work great...    

remember.. push the tube all the way in to the fitting before trying to shove the tool in..  this frees the latches to allow them to expand easier for tool entry...  

Thanks Wayne and others for all your help. Well, i learned a very important lesson. Read your Repair Manual before doing work on your vehicle. Just because something was one way in another ford vehicle doesn't mean it's the same in another ford vehicle.
 Originally i thought i had a blown head gasket because when i drained some of the radiator fluid( or so i thought it was the radiator drain plug) black looking fluid came out looking like oil. But as i began to inspect the hoses I couldn't find any gunk coming out of the Heater core hose nor the radiator hoses. Well, where i made the mistake was not reading my repair manual for the car i just got.
 You see, before this car, I had a 1991 Ford Ranger and when i went to look for the Radiator Drain plug underneath my 1995 ford escort wagon, I gravitated to one plug and assumed it was my Radiator drain plug. It was in the same proximity and had about the same look as the Radiator Drain plug in the 1991 Ford Ranger and I just assumed it was my radiator drain plug for the Ford Escort. Problem was that it wasn't the Radiator Drain plug. It was the plug for the Transmission coolant line which natural has TRANSMISSION fluid in it, not radiator coolant. I pulled the Transmission coolant plug out instead of the Radiator drain plug, freaked out when i saw black and thought the worst. Come to find out my 1996 ford escort doesn't have a plug; it has a valve you turn and it's at THE OTHER END OF THE RADIATOR, LOL. I got the 2 thing mixed up. Next time i need to read my Haynes book before assuming anything.
 So, actually my Radiator fluid turned out fine. Well, it did has some junk in it because that thing apparently hasn't been flushed in a while.  So, what was causing my over heating you ask...Well,The problem, which turned up after running a Radiator pressure test, turned out to be that my Radiator has 2 leaks. After inspecting it, I found 2 leaks underneath the radiator seeping through.I also made sure it wasn't coming from the hosing and just trickling to the bottom instead. My Radiator looks little rusted in some spots so It's time for a new one anyway. $90  for a new radiator and I'll put it in this weekend.
 So, in closing. When doing work on your vehicle, ALWAYS I mean ALWAYS read the manual. Thank you LORD that all i did was just take off the Valve cover instead of tearing the whole top of the engine off, assuming it was a blown head gasket. oh well, $17 for the valve gasket but A WHOLE lot of wasted time that could have been using fixing the real problem.
 Honestly, I'm glad It happened. I learned  more about my car then i would have if i didn't think it was a Blown Head gasket. In a way, I was kinda looking forward to ripping the top of the engine off so I could learn something new. I'm the type of person that loves doing stuff like that so as to learn a new skill and solving the problems that come up on the way.
  Again...READ, READ, READ the Manual before you assume anything because your assumption can be way off. Thanks guys.

Oh wait... I still have a Radiator to put in...I'm sure I'll be back.  

want to have some fun.. with cars when its NOT so cold...

load your tools (tools only no parts)  and a small wagon or drag behind dolly... a bottle of water.. drive to the local pick your part..    spend some time looking at similar models that have been ripped apart in the junk yard..

its a learning experience..   i used to spend a LOT of free time wondering junk yards . with a 5 gallon bucket with a few carefully selected tools and screw drivers.. always a magnet on an antenna tool.. so you can retrieve dropped tools .. yep it happens to the best of us..  

the trick is to take a few simple things apart with care.. and NOT break them.. as somebody else might need them.. only to find them removed properly and ready for them..  

i love going in a junk yard.. finding the exact parts i need already removed.. laying there waiting for me..  it happens more times than i could count..



when you have parts to buy..   you can also pick up the various screws and fasteners for your car.. as most don't charge for the nuts and bolts you pick up as long as you buy something ..  handy to have extra fasteners when working on cars..

i have also gone to the junk yards to try to reverse engineer how a system works...  so i don't have to rip a customers car to pieces to try to figure out why its acting stupid..

i have gone as far as pulling entire dash boards .. not just the display.. the WHOLE dash.. to get to the wiring on the inside of the firewall.. to split it open to trace the wiring..   as one circuit fed about 6 different devices on this caddy.. and i could not figure out where it got its power from..   it was the electro luminescent circuit.. that varied the brightness to the dash.. the ac display.. the radio.. the displays on both sides of the column..  i never did figure out where it got its power from...  

Wayne, I'm in bit of a predicament. I need to clean the junk off my valve cover bottom to prepare it for the new gasket to put on. I don't get off until dark and it's been rainy so I want to bring the valve cover into my house so I can clean it but that would require me to cover the top of the engine to keep moisture or junk out of my engine while the valve cover is off for the night. Is it okay to put some plastic wrap or something over the uncovered engine so I can keep the valve cover inside, overnight, to clean it?
 I'll be off Thursday morning so That's when I'll do the engine part of it, but I need to have as much done as possible before then. Meaning..the valve cover. Recommendations??  

cleaner degreaser from smart and final or cash and carry stores.. can be used as a parts wash..   its like 409 or fantastic but stronger.. washed with hot water... will remove any grease hopefully..

yes.. food wrap may protect the engine from moisture..  

hey wayne, having hard time getting jumper cables from positive battery terminal to the connection on the starter, is it okay just to go ahead and buy a remote starter like above and use that?? wasn't sure if the wire on the remote starter would be thick enough?? If not then what gauge speaker wire would be thick enough??  

Wayne, I was thinking. We were talking about the battery and it not being fully charged but isn't a normal car battery a 12 volt battery?? I was getting 11.99 or 12 volts from the digital multimeter so the battery would be find then wouldn't it??