90 Civic valve issue...

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meld_b

I bought a 90 Civic Hatch at 129K from a mechanic who told me that the
valves were just redone.... We I found it was consuming oil I took it
back and he fiddled with the PCV and declared it fixed. When it wasn't
he started saying Oh-well...and I'll sell you this other car, classic
evasion... I basically just kept driving and watching the oil. It
doesn't emit smoke at all when started but under load and when cold it
smokes more. I think it eats a quart in 300 miles.. One question is, if
you fix the head do you usually need to fiddle with rings? (complete
rebuild?) The other question is, is how is it possible that compression
checks out (or it used to) and it still burns oil?

Recently, while at highway speeds with not as much oil as I'd like on
the dipstick (at the bottom hole) I felt a surge and a loss of power,
and it was rather rough after that. Now it wobbles at low rpm but at
high speed I almost can't tell.. Mechanic says there is one piston with
not much compression. He said the plugs were pretty fowled and put in
new. The Engine light had been seen a couple of times and I was getting
ready to put an 02 sensor and plugs in.

So any opinions? Shoot the thing and move on?

-D
 
I bought a 90 Civic Hatch at 129K from a mechanic who told me that the
valves were just redone.... We I found it was consuming oil I took it
back and he fiddled with the PCV and declared it fixed. When it wasn't
he started saying Oh-well...and I'll sell you this other car, classic
evasion... I basically just kept driving and watching the oil. It
doesn't emit smoke at all when started but under load and when cold it
smokes more. I think it eats a quart in 300 miles.. One question is, if
you fix the head do you usually need to fiddle with rings? (complete
rebuild?) The other question is, is how is it possible that compression
checks out (or it used to) and it still burns oil?

Recently, while at highway speeds with not as much oil as I'd like on
the dipstick (at the bottom hole) I felt a surge and a loss of power,
and it was rather rough after that. Now it wobbles at low rpm but at
high speed I almost can't tell.. Mechanic says there is one piston with
not much compression. He said the plugs were pretty fowled and put in
new. The Engine light had been seen a couple of times and I was getting
ready to put an 02 sensor and plugs in.

So any opinions? Shoot the thing and move on?

-D
Click to expand...

One problem with engines that have over 100,000 miles is that the rings
wear out. If that happens, the only solution is to take the engine apart
and replace the rings. In some cases, the damaged rings may do some minor
damage to the cylinder walls. This means those walls have to be worked on.
A mechanic may charge you over $1000.00 to do this sort of work since it
takes lots of time. I advise you to trade it in on another car unless you
really love the car. Of course, I could be wrong so you might want a
mechanic to take a look at it in case it's a more minor problem.
 
meld_b said:
I bought a 90 Civic Hatch at 129K from a mechanic who told me that the
valves were just redone.... We I found it was consuming oil I took it
back and he fiddled with the PCV and declared it fixed. When it wasn't
he started saying Oh-well...and I'll sell you this other car, classic
evasion... I basically just kept driving and watching the oil. It
doesn't emit smoke at all when started but under load and when cold it
smokes more. I think it eats a quart in 300 miles.. One question is, if
you fix the head do you usually need to fiddle with rings? (complete
rebuild?) The other question is, is how is it possible that compression
checks out (or it used to) and it still burns oil?
Click to expand...

Often times, simply replacing a head gasket or doing other head work on these
motors without doing any work on the rings will lead to high oil consumption.
It is best to rering the engine in order to ensure that this problem does not
occur.
Recently, while at highway speeds with not as much oil as I'd like on
the dipstick (at the bottom hole) I felt a surge and a loss of power,
and it was rather rough after that. Now it wobbles at low rpm but at
high speed I almost can't tell.. Mechanic says there is one piston with
not much compression. He said the plugs were pretty fowled and put in
new.
Click to expand...

It sounds like this mechanic may be trying to cover up something. It there's a
cylinder low on compression, then you need to find out why. For example, is the
compression loss occurring past the rings or via the valves? If it's past the
valves and this mechanic did the valve work, then he could be held responsible.
Note that you may want to take it to another mechanic for diagnosis in order to
obtain (hopefully) an unbiased and honest assessment of the situation.
The Engine light had been seen a couple of times and I was getting
ready to put an 02 sensor and plugs in.
Click to expand...

If the engine light has come on, then it might have set some codes in the ECU.
The codes are accessed by pulling up the front of carpet on the passenger side
floor, turning the key to the on position, and then counting the number and
sequence of the LED flashes.

Eric
 
Thanks guys - There are two mechanics involved... The one that did the
valve work and eventually admitted that he didn't work on rings - Which
I've now learned he should have. (Hindsight is 20/20)

The second mechanic is much more trusted and I believe him when he says
the compression is low in one cyl. I just put some Marvel's Mystery
Oil in for the fun of it, and it is significantly less wobbly! It's
still there when going just at the wrong RPM. I have started looking for
another vehicle. It's neat how it is STILL moving me around!

Did Honda change any designs so that later years would be less likely to
have this sort of thing happen? Is the Accord different than the Civic?

-Dan
 
|Thanks guys - There are two mechanics involved... The one that did the
|valve work and eventually admitted that he didn't work on rings - Which
|I've now learned he should have. (Hindsight is 20/20)
|
|The second mechanic is much more trusted and I believe him when he says
| the compression is low in one cyl. I just put some Marvel's Mystery
|Oil in for the fun of it, and it is significantly less wobbly! It's
|still there when going just at the wrong RPM. I have started looking for
|another vehicle. It's neat how it is STILL moving me around!
|
|Did Honda change any designs so that later years would be less likely to
|have this sort of thing happen? Is the Accord different than the Civic?

If the car is otherwise sound and everything works, why don't you just have the
motor changed? You should be able to get that done with a low-mileage engine
for about $1000, maybe less. Then you'd have a car that would serve you well
for years.
Rex in Fort Worth
 
|Thanks guys - There are two mechanics involved... The one that did the
|valve work and eventually admitted that he didn't work on rings - Which
|I've now learned he should have. (Hindsight is 20/20)
|
|The second mechanic is much more trusted and I believe him when he says
| the compression is low in one cyl. I just put some Marvel's Mystery
|Oil in for the fun of it, and it is significantly less wobbly! It's
|still there when going just at the wrong RPM. I have started looking for
|another vehicle. It's neat how it is STILL moving me around!
|
|Did Honda change any designs so that later years would be less likely to
|have this sort of thing happen? Is the Accord different than the Civic?

If the car is otherwise sound and everything works, why don't you just have the
motor changed? You should be able to get that done with a low-mileage engine
for about $1000, maybe less. Then you'd have a car that would serve you well
for years.
Rex in Fort Worth
Click to expand...

That's great advice and I should have mentioned it in my post. Thanks for
your excellent post.
 
Yes, it still gets you -- and me -- "around" even with one cylinder
with low compression...in my case it's #2 cylinder which has 27 pounds
and it's been that way for about 4 years now!

Why don't I get it fixed? For one thing, try to find another 1973
Datsun 1200 engine in an auto salvage yard or even a remanufactured
engine somewhere...the A12 engine isn't evenlisted on such an old car
like this one, or, try to find parts for rebuilding an A12. Probably
REALLY expensive even if I DID find an engine. Besides, it runs pretty
well considering, but yes, I DO plan to get it rebuilt somehow and
restore the car at some point if possible.

My point is, these Japanese cars -- even "wounded" -- can be pretty
reliable and definitely "get you around" despite their ills! Can't
complain here!!

John D.
 
Wow - 4 years! I find it a little scary with all the SUV's around
pulling out into traffic, with a engine that isn't really all there.

My wife is opposed to putting an engine in this car... I only paid about
$2500. Engine availability is not really the problem. I was thinking of
checking the milage one last time and putting it in the paper. See what
I could get.... I see all these "engine needs work" at the same year for
$800, Edmunds says more like $500 for "Average" or "Rough"

-D

I did see that there are lots of engines around
 
Yeah...but you couldn't tell anything was wrong listening to it
idling.

As for SUVs, I'm in no hurry like most everyone else is, but I stay in
the right "slow" lane regardless...they can pass me all they want.
Let's see if ANY of them are still on the road in 30 years...probably
not...I pass a lot of them broken down on the shoulder or "camping
out" on the freeway medians during holidays. ;-)

John D.
 
John D. said:
Yes, it still gets you -- and me -- "around" even with one cylinder
with low compression...in my case it's #2 cylinder which has 27 pounds
and it's been that way for about 4 years now!

Why don't I get it fixed? For one thing, try to find another 1973
Datsun 1200 engine in an auto salvage yard or even a remanufactured
engine somewhere...the A12 engine isn't evenlisted on such an old car
like this one, or, try to find parts for rebuilding an A12. Probably
REALLY expensive even if I DID find an engine. Besides, it runs pretty
well considering, but yes, I DO plan to get it rebuilt somehow and
restore the car at some point if possible.
Click to expand...

That's fine for such an old car. All you loose is some power and loss of
mileage. However, for a more modern car such as the one under consideration in
this thread, the low compression will lead to excessive emissions due to
incompletely burned fuel making it difficult if not impossible to pass an
emissions test. Moreover, this will likely also cause the catalytic converter
to overheat and shorten its life. The incompletely burned fuel could also wash
the rings of oil on that cylinder leading to greater wear.

Eric
 
Eric,

I didn't say it was "fine" for ANY car -- it isn't -- I'm just poor.

But maybe the original poster is NOT poor...he should get it fixed as
you suggest.

I was just stating what a car can do even though it's not 100%. My car
has even "fixed itself" on occasion. Amazing. Can't fix its #2
cylinder though...

John D.
 
No - I'm not poor just "cheap" well... actually saving up for the house
addition 8-)

I'm still bombing around in this thing. I'm about to fill up and assess
the milage to see how much raw gas is going by. My last few tanks were
37.4,37.2,37.7,40.2,34.1 (the problem happened at the tail end of the
last tank) It is interesting how at highway speeds you can't tell there
is anything wrong. Going up a hill from a stop is very rough. The
frequency and amount of shaking seems to shift around...

What's a good theory? A piece of valve broke off? or maybe a piece of
ring? and stuff gets plugged in there and that's how it could "fix" itself?

If the emmissions test 'round here had any teeth in it I wouldn't have
been able to buy this car in the first place. This would have been a
good thing! The guy who signed the inspection sticker had the valves
done and just glanced at the cylinder and declared it "In great shape"
he didn't check compression... OK so I'm learning.

The big question is: I had since checked compression to be 140-145 on
all 4 when it was burning oil... so Is this in spec? If so, what do you
have to do to make sure you've got an OK engine? A leakdown test?

-D
 
If you add a couple of squirts of oil to the problem cylinder and redo the
compression test you should be able to determine if it's the rings or the
valves. The compression should come up if the problem is in the rings, while
there should be little change if it's the valves.

Eric
 
Meld,

Glad you're just cheap instead of poor...there's enough of us poor
folks already! I want to save up, too, not for a house but for an
older "classic" Class A RV for full-timing it. Don't like apartment
living, don't want a house at this point in my life.

As for emissions checks here in TX, they ARE tough, but cars 25 years
old are exempt...safety inspection only for the oldies. Besides, the
car doesn't smoke so it's not a noticable problem but still, not sure
what the cause is.

As for your case, try Eric's test, but you may not know for sure until
you look inside...either by using one of those endoscopes
(camera-probe through the spark plug hole, preferred) or taking the
head off (a job in itself). If a piece of valve or ring broke off,
your cylinder walls are probably scored pretty well.

Good luck,

John D.
 
Thanks guys - I keep reaching for chemical solutions... Engine restore
will help me with the scored pistons right? I wonder how to find someone
with a REAL manual that will tell me the target compression. The
Chilton's that I've found in a local library don't seem to have the numbers.

-D
 
meld_b said:
Thanks guys - I keep reaching for chemical solutions... Engine restore
will help me with the scored pistons right?
Click to expand...

Most of the "mechanic in a can" solutions are wishful thinking. Although I'm
not familiar with this specific product, I would be suspicious any product that
claimed it could fix scored pistons and cylinders.
I wonder how to find someone with a REAL manual that will tell me the target
compression. The Chilton's that I've found in a local library don't seem to
have the numbers.
Click to expand...

250 rpm and wide open throttle
nominal 185 psi
minimum 135 psi
max variation 28 psi
 
Thanks - I'm learning here... Is 250 RPM what the starter spins? What
does the wide open throttle do for you? I'm thinking these numbers are
what you use to compare to when you have a four plugs pulled and you put
the compression checker in each cylinder and have someone crank it? So
they need to floor it too!?

I measured 140-145 on all 4 before the incident and it was burning oil
like crazy ... so I must have done something wrong... or loss of
compression isn't why this was burning oil. The PCV was checked and
thought to be fine. I feel like I need to learn this lesson before I buy
the next car.

-D
 
It is a red flag to me if someone says thay have done the valves on a
car with high mileage. Engines tend to age gracefully if well cared
for, and that means the top and bottom end age together. So, when you
do the top end and restore full sealing power and compression to the
engine, it can spell trouble for the older bottom end, leading to ring
and cylinder failures.

If thi car is in excellent shape otherwise, look around for a short
block and put it in. Can't be more than $1200-$1300 total.
 
meld_b said:
Thanks - I'm learning here... Is 250 RPM what the starter spins?
Click to expand...

I don't know since I've never clocked it but it probably is the cranking rpm
(on a fully charged battery).
What does the wide open throttle do for you?
Click to expand...

Maximizes air flow, allows the engine to breathe, helps give you the highest
possible compression numbers, etc...
I'm thinking these numbers are what you use to compare to when you have a
four plugs pulled and you put the compression checker in each cylinder and
have someone crank it? So they need to floor it too!?
Click to expand...

Yes, or use a brick or pedal depressor and a remote starter switch (and make
sure the car's out of gear so you don't run yourself over).

Eric
 
Thanks - I think running over yourself trying to fix a car worth about
$600 would have to put me in the running for a Darwin award!! 8-)

No this car isn't in that great of shape, starting to rust on one side,
axles about to go. Heater blower has brushes that are suboptimal. And
most importantly, my wife doesn't want me fiddling with new engines,
etc. So I'm probably off to something new, when I can get around to
it... It is nice how it's giving me time by still moving me around.

-D
 
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