First off I am new to tearing into motors. I have worked on and fixed mechanical and engine parts and problems in my back yard but this is my first experience with a real seroius problem that requires motor dismantal.

I did a complession test on a 2.4L motor the other night to see if the head gasket was bad and here are the results.

Cyl1= about 48psi
Cyl2= about 45psi and pulsed wile turning over the motor
Cyl3= about 48psi(same as cyl1)
Cyl4= about 53psi

I do not know what PSI this motor (Toyota) should be getting but I am also not sure what this tells me. I was told if two cylinders near each other were low than the head gasket was gone between the two but that is not the case here.

Any help is appreciated..
Thank you

Do I possible have more problems than a blown head gasket??.....

 

Does the engine run?
I would guess the compression should be in the 120-150 psi range.
If your compression tester works properly and you have such low compression on all cylinders that would point to a jumped timing belt or chain....whatever a Toyota uses.

 

Moved to proper forum.

 

I agree, sounds like jumped timing chain or belt. All of your readings are very close to each other, so no head gasket problems.

There is no way it should run on the compression you are showing.

BUT, if it does run, then check the compression again, but hold the throttle wide open when cranking over the enging to make sure the cylinders are receiving enough air to give a correct reading.

 

do two compression test. The first one,open the throttle all the way. The second time,squirt oil into the cylinders first,spin engine over, then take test. If compression raises you could have ring problems.
Also check your cam timing.
Has the engine ever been overheated. Taht would kill the compression rings

 

Here is waht I have found so far.

The truck did overheat as the radiator poped. I bought the truck(got a deal) with blown rad and possible blown head gasket.

I took off the valve cover and it looked like chocolate milk(Yu-Hoo) inside it. I removed the head and brought it to a machine shop. The guy took a quick look at it and said the head was shot due to cerosion. There was pitting where the head gasket seal would sit. He does not have the equipment to fix the cerosion problem and there is no place localy he kew of that did it. his shop deals with a place in South Carolina(I think). He said he could machine the warpage out but the corosion divit would get bigger and after an unknow time(2 weeks or 2years) water would be put back into the cylinder.
Before taking off the head the timing chain looked and felt real tight. Also the cylinder walls had no scoring or even substancial wear I could feal with my fingernail.

I'm now in the search of a new head. For a popular motor these heads are either really expensive or hard to find. 5 local shops have them referbed for $350-$500(without core charge) and only 2 of the 8 local salvage yards have any.

And thank you for moving the thread. I had no clue where to put this so I figured all 4 cylinders are similar.

 

Since you have the head off, take some solvent and pour down each cylinder enough to cover the top of the piston and see if stays there for a while or goes by the rings real quick. if it goes down real quick,the rings are shot

 

Its at the shop right now. I found a shop that can deal with and fix cerosion pitting.

An inspection by the shop of the head gasket shows that the head worped and there was blow by going between the first 2 cylinders and the second 2. The first 2 had a grater blw by. The head gasket was not bad to the point where there was leaking into the cylinders from the water jackets.

The shop also say marks on the head that matched marks I found on the timing cover and pointed to a broken timing chain guide. I saw 1 and thought the marks were from a previous loose or broken chain but the shop said there are supposed to be 2 guides, so the timing being out is a possibility also.

 

I might have found a good used head.

Is there anything I can do to make sure the head and valves are good?
I was told to put either oil or water in the top of the valves and see if any leaks through. Is this correct? Any other little things I can do to check integrety of head?

 

if the head is off the best way to check it is have a machine shop do it. If your head is warped do NOT have it machined flat. This fixes the mating surface but does nothing for the overhead cam. The best bet is find a machine shop that has an oven and they can heat it and straighten it correctly. If the engine is still together you can. do a wet compression check which is using the oil to seal the gap where the rings are. the only other thing you can do isrun each cylinder to top dead center and used compressed air if the air leaks out the valvecover it is bad valve guides