First of all, I am doing this because my car won't start. It will turn over, but won't start. Fuel pump primes and there's fuel in the chambers also. There's also spark to all 4 plugs. My dad and I just did all of this as well as made sure the timing was spot on.

Although it is supposed to be done at N.O.T., we did a compression test. The numbers came back 60, 30, 100, and 90; cylinders 1-4 respectively. Keep in mind, these are cold numbers, but the variance scares me naturally.

This brings me to my current situation. I woke up at 4:30 in the morning for no apparent reason. Well actually, this is not true. Apparently fate would have it that I feel I should take a look at the valves, cylinders, and pistons this morning. Here is what I came up with.













I'm probably gonna take the head up to a shop in the area, since pics don't always say enough, but any input you all have, I would really appreciate it!

-Shane


Modified by nighttrain33 at 7:30 AM 4/8/2008

 

Also, sorry about the large pics, I'll try resizing them for everyone.

-Shane

 

Was this compression test done after the multiple times you tried to start it without luck? The extra fuel in the chamber could have temporiarily "washed" out the rings causing bad numbers. "Could" is the magic word.

GL!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by blk92_d16 &raquo;</TD></TR><TR><TD CLASS="quote">Was this compression test done after the multiple times you tried to start it without luck? The extra fuel in the chamber could have temporiarily "washed" out the rings causing bad numbers. "Could" is the magic word.

GL!</TD></TR></TABLE>

No, they were done on 2 separate days.

Well, I took it to a shop in the area (even though everything looks fine to me) and he agreed. So now I get to put it all back together and start over again.

-Shane

 

your seats look pretty bac. whats the milage on the head? id say get a 3 angle real quick

 

You can try a 3 angle ..

 

i dont know what kind of car you have but these are specs for a 97 dx hb. and yours would fail by a long shot. granted you may have a diffrent motor but i dont think it really matters cause those numbers are garbage by any standards

Compression [1]


Nominal 1,270 kPa (184 psi)

Minimum 930 kPa (135 psi)

Maximum Variation 200 kPa (28 psi)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RS2 FAB &raquo;</TD></TR><TR><TD CLASS="quote">your seats look pretty bac. whats the milage on the head? id say get a 3 angle real quick </TD></TR></TABLE>
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by changeYYYY &raquo;</TD></TR><TR><TD CLASS="quote">You can try a 3 angle ..</TD></TR></TABLE>

Please dont let this be your first step to try and fix this problem. Im not saying that the valve seats are good or bad, but a compression test does not test how your valves are seating at all. It is ment to diagnose piston rings for the most part. If you are going to try and diagnose it as a valve seat problem. you need to either put the moter back together and do a cylinder leakdown test or else with the head off lap the valves and see how the are seating. Just trying to save you some money.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LS-V Turbo &raquo;</TD></TR><TR><TD CLASS="quote">i dont know what kind of car you have but these are specs for a 97 dx hb. and yours would fail by a long shot. granted you may have a diffrent motor but i dont think it really matters cause those numbers are garbage by any standards

Compression [1]


Nominal 1,270 kPa (184 psi)

Minimum 930 kPa (135 psi)

Maximum Variation 200 kPa (28 psi)</TD></TR></TABLE>

It's a B16. I will be doing a leakdown test when I put it back together, but I am fairly certain that somehow we got the timing wrong. I don't know how since I have had to do the timing before, but the guy at the shop said the head is fine and personally I think the cylinders and pistons look great.

From people I've talked to, they believe it has to be the timing. Also, I am not sure if my dad let me give the car enough cranks on each cylinder to get a good reading on the compression test. It was cranking pretty badly that day (bad battery charge).

-Shane

 

my z6 had the same issue,

blew the rings. i could literally baley push down on the piston and it would slide, when i took the rod cap off the piston fell out of the block and ring bits fell all over the floor. as well as part of my ring lands

also i ripped apary an XSI block (which is a b16a obd0) same thing.

but you need to get that head done. it's just ontop of all the **** you're going through did you do a dry AND wet test?

dude 30psi in cyl 2 is not a timing problem