onelostcoupe

So I have a 2000 civic, didn't run when I bought it and was told the compression was low. Ran the numbers and it's like 10-50psi on all 4 cylinders. Timing belt is in good shape and the mechanical timing is good. Any ideas? No oil in the coolant and no coolant in the oil so I don't think it's a bad head gasket. This really seems like the timing belt snapped, smashed the valves and they threw on a new timing belt? I can't really think of anything else. Unless they ran a **** load of dirt into the engine and destroyed the rings on all 4. But I find that highly unlikely.

Chance EG

If you're getting 10-50psi across all 4 cylinders, the internals are toast.

onelostcoupe

yeah, she's fucked. Took the head off and number 4 piston doesn't move. I don't really understand how that would **** up the compression on the other 3 though.

Tylers88

Time for a b swap and make it fun

Chance EG

Probably. Don't waste your time or cash just replacing it with another D.

Pretty sure you could do an LS swap for the same cash, or a B16A for slightly more. Either would be more fun, just as reliable, and probably about the same MPG.

Depends on what you want to use the car for but there's a ton of options.

onelostcoupe

******* wow. I pulled the motor and prepped my spare d16y7 to drop in, got it installed to the point where I could run it and guess what? This motor is fucked too, same cylinder 4 with a thrown rod. I got scammed as **** on craigslist.

Tylers88

That sucks to hear about the spare

onelostcoupe

Incredible someone would intentionally rip someone off like that. He insisted it ran great when pulled. But the fact that the piston doesn't even move shows it was ran hard until it died.

On that note, why does that happen? This replacement motor has the same problem my original one did, cylinder 4 threw a rod. And I've also seen that happen on a friend's 94 civic D15B7.

Does the oil pump go bad and cylinder 4 is the furthest away? Or Did all of these civics run low on oil and one hard left or right turn sloshed the little bit of oil away from the pick up?

Jimi Hondrix

Scammed on Craigslist? No way!..lol
Did you buy an already pulled motor or one that was running that you could test?

NVturbo

That happens everyday. People will take advantage of others whenever they have the chance. A few months ago, I met up with a seller on Craigslist selling a set of "used" Integra tail lights. When I got home and thoroughly checked, one of the lights had a noticeable crack on the side portion. Contacted him and he acted like it was in perfect condition when he handed them to me. ****** shady asses.

Don't sweat it. Karma is a bitch. POS that do stuff like that will get their day.

dck1ng69

Craigslist transactions definitely force you to improve how thoroughly you inspect future purchases. I recently got a "complete A/C system" pulled from a civic and didn't do enough research to realize that he skimped me on a few small parts, that aint happening to me again. Stock D series motors though aren't really designed to be abused, they're fuel economy engines, that's why so many people blow them up imo. Do an ls or b20 swap

tony_2018

Low compressoin? Ok to boost, than buy another motor.

Tylers88

You may be out the money and an engine right now but I'd go dump the bad engine in his lawn in the middle of the night

NVturbo

People blow up D series engines along with any other engine due to carelessness and neglect. 99% of the time, they have no clue what they're doing anyways....hence my sig.

onelostcoupe

I wish I could have checked it further, I guess I should have brought a spark plug socket and put a rod into the cylinders to check if 1 and 4 moved in sync and 2 and 3 moved in sync. But I did test if it turned over with a breaker bar which it did. I didn't think it was too much effort to turn it over either.

Matt_EH3

Get yourself a compression tester and carry around a spare battery when checking engines. The cold compression test will not be accurate, but you will at least know if all parts of the engine are moving.

onelostcoupe

Wait, how would I do a compression test if I'm just buying a motor? The starter bolts to the trans? This particular motor had no flywheel, no pressure plate, no trans, nothing.

Matt_EH3

Ah, good point. Never mind then. I guess I never bought a tranny-less motor

joey1320

You prop open the throttle butterfly and attach a socket/wrench to the crankshaft bolt and spin the engine manually. It's not going to give you the most accurate readings but as long as they are all within 20% stock, the you have a healthy engine.

mk378

Just removing the spark plugs to look at the business end of them can tell a lot about engine condition. If the spark plugs are in and the timing belt is on, you should feel compression resistance every 180 degrees you turn the crank. If you feel compression, compression, then it just spins over through one cycle, there is a dead cylinder.

tamboo

here's to hoping it aint melted!

https://www.ngksparkplugs.com/about-...d-a-spark-plug

Jimi Hondrix

To add to this: Remove all spark plugs first for easier cranking. Follow up the dry test with a wet (cap full of oil) test in each cylinder. If compression rises significantly then could be a compression ring(s) issue.
Also, as mk378 mentioned..inspect spark plugs:

Rick Nelson

You need to run a leak down test to diagnose the source of compression loss. It could just be stuck or burned valves and lower end ok. For example exhaust or intake valves that are stuck open can give you zero compression on one or all cylinders depending upon which valves are open. Specific diagnosis cannot be precise without doing a simple leak down test which much be done on each cylinder with all spark plugs out, throttle propped open, dip stick removed, radiator cap off, valve cover hose to throttle intake disconnected. But a 40 buck leak down tester and follow instructions to the tee.

You can isolate the source of a leak pretty easily this way. The key thing is to know how to put each cylinder tested on top dead center on the compression stroke while testing that cylinder. there are lots of good youtube videos that show you how to do it.

You Tube

Just buy one of the testers in stead or trying to rig one.

Examples: If you have air under pressure leaking out of tail pipe, you know you at least have a bad exhaust valve. If you leak from your open throttle, you have a stuck open intake valve. just google for more indicators for this simple test. Also if you have bubbles in radiator fluid cap area, you can count on at least head gasket. ALWAYS run on TDC compression stroke or the test is worthless.Many videos show you how to do this. I use a small balloon on my comresssion hose tube and turn the crank counterclockwise until the balloon inflates some and then a wood dowel in the spark plug hole to touch the piston and fine tune it to the precise TCD. Mark the dowel beside the top of the spark plug hole and use that mark to double check the height on the other cylinders.

Remember, do not let anyone tell you that a compression test is not sufficient.