Replaced the head gasket and not getting any compression.

[kiamors]

My motor was eating coolant and had several other issues such as a leak at the turbo/ exhaust manifold joint, and some issues with a few motor mounts. So after taking the motor apart and fixing everything and putting it back together, minus the radiator and intercooler, I tried to fire it up to make sure it would run, but it would not start. upon testing the compression it was lacking. 30-60-0-60 was the numbers we got. since the motor was running fine before the head gasket was changed, we took it down to the head and took the head back to the machine shop. before we took it back we did the water test and the valves did appear to be leaking. of course the machine shop did complain about fixing it but the did eventually take it back. upon putting it back on again with a new head gasket and new head bolts and putting the engine back together again it still did not start. I will start compression testing tomorrow as it was quite late when I was done.

What I am wondering is is there anything that could cause the car to not start after having the head gasket replaced? it is acting like it does not have compression again but until I test it tomorrow I wouldn't know.

has anyone experienced this problem or have any ideas as to what else might be causing it.

 

[Jo060]

Could the timing been changed on accident?
Did you re torque everything to spec?
Rocker arms ok?

 

[kiamors]

The head was torqued to 15 ft/lbs and then the bolts turned 90 degrees and 90 degrees, which is to the specs as listed in Alldata (the computerized car repair manual that mechanics use. my friend who is helping me is a professional mechanic.) The timing was set and checked according to alldata as well. (line up the notch on the crank with the rib and align the marks on the intake and exhaust cam gears. it was spun around twice and the notches still matched every time.)

as for the rocker arms, I am a bit rusty on my engine terminology but I don't believe that the 2.0 engine in the mazdaspeed has them. It is a DOHC setup which eliminates the need for rocker arms. my intake and exhaust cams interact directly with the lifters. but all of these things have been double checked by my friend who is a professional mechanic and who supervised me doing the work. Im about to head over there and start again today.

 

[justanothermp5]

if the engine was making compression before, it could only be the head gasket or the valves.
You used a different head gasket each time right?

 

[kiamors]

I used a different head gasket each time.

But I have an update. after spending 4-6 hours monkeying with it and trying different things and testing this and that, we have figured out that it is something to do with the head gasket or the head itself. we ended up pressurizing the cylinders individually to see how and where they where leaking. also to test for leaks in the head or block. turns out the cylinders are leaking into each other. so we figure either the head gasket we replaced is faulty, the machine shop shaved off a bit too much when they planed the head, or the head or block got warped somehow. my vote is on the head being shaved a bit too much since the pins that you use to line the head and block up where sticking into the head when I pulled it off last. they shouldn't be doing that, so we think the head got shaved a bit too much and the pins are keeping us from torquing it down correctly and causing the leak.

time to search for a thicker head gasket and I guess take it apart next weekend and check to see if they are warped.

I saw some threads about thicker head gaskets in the forums when I was researching the problem last night so im gonna go back and read some more but does anyone know if I could just put on a larger head gasket without experiencing any major problems or would this change the compression on the engine too much?

 

[01CrznMp3]

The pins are normal to be up in the head after surfacing the head. You have to hammer them um or pull them out in order to have a flat surface to deck the head. Sounds like to me that you got the timing out. Make sure the I on the intake cam and E on the exhaust point at eachother on the center of the head. And yes there are thicker headgaskets at a price, I got a Cometic .051 on mine and they run $124 Shipped. There is a downfall though that it drops your compression even more. I lost 25-40 lbs with this gasket. Check out this video though, the guy did a great writeup. http://www.youtube.com/watch?v=k6lJ_3yw_Tc

 

[hornsfan10609]

Thanks for posting that video. Answered a lot of question for me, i'm tearing down my motor to replace the head gasket right now and i'm a little lost.

 

[01CrznMp3]

No problem, keep us updated on how things are goin. If you need anymore help let us know.

 

[nopistons3]

There is a small thing some people forget when aligning the timing marks. Make sure #1 piston is at tdc on Compression stroke! Some people get that confused. I did once years ago n smacked myself for it. Good thing protege engines are non interference!

 

[hornsfan10609]

No problem, keep us updated on how things are goin. If you need anymore help let us know.

Head gasket install went just fine, cranked right up once the injectors finally had fuel.

 

[kiamors]

just got my car back to running ended up buying a new used engine with half the mileage as my old one to fix the problem. The problem was the machine shop I went to didn't cut the valves down like they are supposed to since the MSP has solid lifters, and sadly we didn't realize this until months afterwards. Needless to say I was pretty pissed but it should be back on the road by the end of the week. I can't wait, and I now have an extra engine that I can forge, and then switch back in with my new head or have my old head modded.