Hi I just wanted to get some opinions on the health of my evo's engine. Evo 9 MR with 62K. No power upgrades other than what was leftover from previous owner - fuel pump and boost controller

Cylinder Compression Test
Dry 128-135-135-128
Wet 135-140-140-135

Leakdown Test
18%-20%-20%-20%

I've read brand new the cylinder compression is supposed to be 163 psi. The numbers do seem low but they are consistent. And on the leakdown gauge 20% is right in the middle of the "good range" but the evo's a performance car so I wasn't sure if that's too high. During the leakdown test any air I could hear was coming out of the dipstick or the cylinder next to the one being tested, but in either spot the sound was faint. I do not know the previoius owner and how modded the car was when i bought it (10/11 w/52K miles). I have noticed the car runs hotter compared to my first evo and I can smell that sweet coolant smell while the car is stopped at lights, etc. sometimes I can smell oil as well. I also did a coolant system pressure test - radiator seemed to hold at 15 psi but the radiator cap couldn't hold pressure (bought replacement, hasn't come yet). No coolant leaks or oil leaks that I'm aware of.

I bought a TBE, intake and intercooler and was planning on getting it tuned afterwards so I wanted to check the engine before adding more power and get some opinions on whether I should investigate further.

Any thoughts?

 

3% leak down is good, 5% is mediocre, 8% is crap

 

Did you make sure that the cylinder being tested during the leak down was at TDC?

 

Lining up the mark on the right cam gear with the mark on the valve cover gets me to TDC for cylinder 1 for the compression stroke correct? I did that, tested cyl 1, rotated the crank 360, tested cyl 3, another 360, cyl 4, another 360 cyl 2.

 

360 or 180?

 

i have the shop manual and it says 145 psi is max. your compression is fine. idk about your leakdown.

 

I wouldn't worry about that compression as its consistent and not too far off, that leak down on the other had seems bad to me.

 

The MIVEC motors have lower compression. Mine with S2's is 135-140 across the board as well, and who knows how your gauge compares to mine. Sounds like it's fine then, unless you're burning oil, or coolant.

 

My 2.3 with Mivec GSC S2's was about 150psi on all 4, tested COLD with WOT.
That was before and after the run in.

 

as someone else said, 145 psi is the hot value for evo 9.

 

Where did you hear air escaping during the leakdown? What gauge were you using?

The percentage is basically worthless if you are using a cheap gauge. What you should be looking at is how consistent the readings are...and in your case they look great. Read up on how to properly perform a leakdown test and give it another try. If anything is wrong the test will tell you exactly what the problem is.

Compression tests are a rather crude way of determining a motor's health. It could easily produce good compression, but have something like a slightly leaking valve that would go unnoticed.

 

was the car hot during this test?

 

I ran the cylinder compression test and leakdown test back to back. It took probably over an hour to accomplish both the dry/wet cylinder compression tests. I'm quite the novice tuner. So the car probably had cooled a considerable amount at that point.

I was using a $40 US General leakdown tester. I do question the quality of the gauge as I could hear air coming back out of the cylinder being tested, leaking somewhere near the sparkplug hole out of a portioin of the hose. Any recommendations on a better gauge?

I did not know the MIVEC tests lower than 163psi. Thanks for the info.

I will rerun the leakdown test next weekend. When I did the test the first time I zeroed the leakdown gauge before attaching it to hose already threaded into the spark plug hole. Felt like I was loosing air just connecting the manifold to the hose but I could be wrong.

I found out the general viscinity of where the car is leaking coolant. It's somewhere around the pump/lower coolant hose. Just need to get under the car and take a look. I got the car's timing belt replaced recently at the same time replaced the water pump and coolant hoses. Maybe a gasket wasn't seated correctly or a hose needs to be retightened.

I just sent the DC Sports exhaust manifold, MR turbo outlet, and MR downpipe to SwainTech to get White Lightning coating. So I'm pretty pumped to get the ball rolling on the first set of power mods. I've got the ETS front mount on its way and the Mil.Spec HFC, Greddy Ti-C sitting on the floor in my room.

Thanks for the help everybody. Cheers.

 

I was able to investigate the coolant leak further. I've attached a few pictures of what I found. Not sure what to make of all the dried coolant everywhere. I pressurized the coolant systems and nothing started to leak. The pressure did drop some (from 19psi to 15psi) gradually but it's wasn't immediate. I sprayed some soapy water over the parts after cleaning them off and didn't see anything. Anybody out there have a similar leak? The splashing on the battery especially interesting. Thanks in advanced.

I recently had the timing belt changed (~3K ago) as mentioned above, and at the same time I had the shop replace - the water pump, the radiator hoses (as you can see), and the thermostat. Maybe when they installed the samco hoses the didn't have them completely sealed? Seems like a stretch. I've cleaned all the surfaces , made sure the hoses were on, bolts tight, and will keep an eye on it.

I tested the radiator cap as well and it definitely is not holding pressure. So a replacement is on it's way.

Again when I'm driving around - I smell coolant at lights, etc. When I get back home check under the car - nothing's dripping. Every 2 weeks or the level of the coolant drops.

 

Looks like its leaking out the top silicone hose.