engine rebuild questions

Am considering options with a 93 dohc that has one #3 cylinder
running 180psi. Engine has 120k and has the oil loss problems, 1
qt per 500 miles. Am planning on doing an 'in-frame' rebuild
with rings, hone, bearings, timing set, oil pump, valve job &
seals, clutch(maybe), water pump. Might as well pull it, right?

Anyway, questions I have a
1.) Where does one find a straight bar of steel in order to
check the 'deck' & cylinder head for warpage?

2.) Is there any ball park numbers of machining costs for a shop
to repair a cylinder head or bore cylinder sleeves as need be?
Should valve guides normally be replaced?

3.) Are third party timing sets from ebay OK?

On Fri, 25 Aug 2006 05:22:45 GMT, CBrooks >
wrote:

>Am considering options with a 93 dohc that has one #3 cylinder
>running 180psi. Engine has 120k and has the oil loss problems, 1
>qt per 500 miles. Am planning on doing an 'in-frame' rebuild
>with rings, hone, bearings, timing set, oil pump, valve job &
>seals, clutch(maybe), water pump. Might as well pull it, right?
>
>Anyway, questions I have a
>1.) Where does one find a straight bar of steel in order to
>check the 'deck' & cylinder head for warpage?
>
>2.) Is there any ball park numbers of machining costs for a shop
>to repair a cylinder head or bore cylinder sleeves as need be?
>Should valve guides normally be replaced?
>
>3.) Are third party timing sets from ebay OK?


On the head warpage I would take the head to a shop and have it
checked with you get a valve job done on it. On the oil consumption,
it is not realy that bad and if it runs well otherwise I would switch
to 10w30 in winter and maybe 15w40 (not 10w40) in summer and stop
using 5w30 you will likely cut oil consumption in half or more and get
more life ot of it. 5w30 will go through a worn engine pretty quick at
times. On more thing if you take this route, do change oil about every
2000 to 2500 miles or so as even though you are adding to it, it is
getting dirty faster and increasing wear potenail and oil consumption
too.
-----------------
TheSnoMan.com

"SnoMan" > wrote in message
...
> On Fri, 25 Aug 2006 05:22:45 GMT, CBrooks >
> wrote:
>
>>Am considering options with a 93 dohc that has one #3 cylinder
>>running 180psi. Engine has 120k and has the oil loss problems, 1
>>qt per 500 miles. Am planning on doing an 'in-frame' rebuild
>>with rings, hone, bearings, timing set, oil pump, valve job &
>>seals, clutch(maybe), water pump. Might as well pull it, right?
>>
>>Anyway, questions I have a
>>1.) Where does one find a straight bar of steel in order to
>>check the 'deck' & cylinder head for warpage?
>>
>>2.) Is there any ball park numbers of machining costs for a shop
>>to repair a cylinder head or bore cylinder sleeves as need be?
>>Should valve guides normally be replaced?
>>
>>3.) Are third party timing sets from ebay OK?
>
>
> On the head warpage I would take the head to a shop and have it
> checked with you get a valve job done on it. On the oil consumption,
> it is not realy that bad and if it runs well otherwise I would switch
> to 10w30 in winter and maybe 15w40 (not 10w40) in summer and stop
> using 5w30 you will likely cut oil consumption in half or more and get
> more life ot of it. 5w30 will go through a worn engine pretty quick at
> times. On more thing if you take this route, do change oil about every
> 2000 to 2500 miles or so as even though you are adding to it, it is
> getting dirty faster and increasing wear potenail and oil consumption
> too.
> -----------------
> TheSnoMan.com

180 psi doesn't seem like bad compression to me, what are the compression
readings on all the cylinders? What are all the readings dry? and after
adding oil through the plug openings to seal the rings? Have you done a
compression leak down test? Dry and with oil added? Can you hear air
leakage into intake or exhaust manifolds? Do any of the plugs indicate more
oil fouling than the others? Have you tried any of the chemical ring
cleaning procedures? Have you used a borescope to check the condition of
the cylinder walls?

Always make a teardown and rebuild your final and NOT initial strategy. I
do agree that IF it is necessary to remove the head, then a head rebuild and
inframe ring job should probably be done. Your oil consumption problems MAY
be due to worn valve SEALS which CAN be replaced without removing the head.

I agree with SnoMan that your first strategy to deal with excessive
consumption should be to try different oil viscosities, (and change your
shifting techniques to a less 'spirited' driving style). I also agree with
reducing oil change intervals on engines with higher consumption rates. If
cost is a major factor (or the difficulty getting at the filter if you do
not have any ramps) then it is better to only change the filter every second
change rather than to extend the oil change.

I would continue babying this engine with oil and viscosity and driving
style changes until engine removal is necessary for clutch replacement. You
can do a much better (and easier, and very importantly cleaner) rebuild with
the engine removed.

Re question #2, get local quotes for rebuild/valve job on your cylinder head
from several automotive machine shops. They will normally check for warpage
if asked, and will also check for valve stem/guide wear. Valve SEALS should
always be replaced, your machine shop/rebuilder may have the equipment to
install a better than OEM type of valve seal.

If your cylinders need more than a light (must do) deglazing (or you need a
new clutch) then you should remove the engine for complete out of frame
rebuild with rebore (requires new pistons) or replacement with better engine
block.

Re question #3 - YMMV

In article <B6GHg.468697$IK3.446143@pd7tw1no>, er
says...
>
>
> 180 psi doesn't seem like bad compression to me, what are the compression
> readings on all the cylinders? What are all the readings dry? and after
> adding oil through the plug openings to seal the rings? Have you done a
> compression leak down test? Dry and with oil added? Can you hear air
> leakage into intake or exhaust manifolds? Do any of the plugs indicate more
> oil fouling than the others? Have you tried any of the chemical ring
> cleaning procedures? Have you used a borescope to check the condition of
> the cylinder walls?

Compression should be taken while hot btw.

Normal compression is 185-205 psi
Minimum is 180 psi

I still wouldnt bother taking that engine appart until ALL other methods
are exhausted to reduce consuption. Hardly worth while IMO.

"BläBlä" . S!RCRE4P.C0M>
wrote in message ...
> In article <B6GHg.468697$IK3.446143@pd7tw1no>, er
> says...
>>
>>
>> 180 psi doesn't seem like bad compression to me, what are the compression
>> readings on all the cylinders? What are all the readings dry? and after
>> adding oil through the plug openings to seal the rings? Have you done a
>> compression leak down test? Dry and with oil added? Can you hear air
>> leakage into intake or exhaust manifolds? Do any of the plugs indicate
>> more
>> oil fouling than the others? Have you tried any of the chemical ring
>> cleaning procedures? Have you used a borescope to check the condition of
>> the cylinder walls?
>
> Compression should be taken while hot btw.
>
> Normal compression is 185-205 psi
> Minimum is 180 psi
>
> I still wouldnt bother taking that engine appart until ALL other methods
> are exhausted to reduce consuption. Hardly worth while IMO.

I agree.

IMHE there is a lot of variation between individual compression gauges and
they are not what we would call 'calibrated'. Similarly there is a lot of
variability due to the procedure used, and as you say, the motor should
ideally be at operating temp, but the maximum compression obtained will
still vary depending on outside air temp and altitude (density altitude for
any pilots) and humidity and condition of starter and battery and whether
all other plugs are removed and throttle position and oiled or non oiled
cylinders. The number of strokes to pump to max is also another important
and variable indicator. There are also other factors that may confuse a
compression test like a plugged air filter or catalytic converter or loose
muffler baffle.

IMHO compression readings should be considered relative to each other and
relative to other indicators like oil consumption rates and plug fouling and
evidence of blowby like dirty PCV valves and dirty engine internal (and
often external & underhood). They can be a good indicator for valve
problems but are not a very good indicator of ring condition and often an
engine with seized oil control rings will give great test results due to the
amount of oil on the cylinder walls and compression rings.

As always, YMMV

Private wrote:
> "SnoMan" > wrote in message
> ...
>
>>On Fri, 25 Aug 2006 05:22:45 GMT, CBrooks >
>>wrote:
>>
>>
>>>Am considering options with a 93 dohc that has one #3 cylinder
>>>running 180psi. Engine has 120k and has the oil loss problems, 1
>>>qt per 500 miles. Am planning on doing an 'in-frame' rebuild
>>>with rings, hone, bearings, timing set, oil pump, valve job &
>>>seals, clutch(maybe), water pump. Might as well pull it, right?
>>>
>>>Anyway, questions I have a
>>>1.) Where does one find a straight bar of steel in order to
>>>check the 'deck' & cylinder head for warpage?
>>>
>>>2.) Is there any ball park numbers of machining costs for a shop
>>>to repair a cylinder head or bore cylinder sleeves as need be?
>>>Should valve guides normally be replaced?
>>>
>>>3.) Are third party timing sets from ebay OK?
>>
>>
>>On the head warpage I would take the head to a shop and have it
>>checked with you get a valve job done on it. On the oil consumption,
>>it is not realy that bad and if it runs well otherwise I would switch
>>to 10w30 in winter and maybe 15w40 (not 10w40) in summer and stop
>>using 5w30 you will likely cut oil consumption in half or more and get
>>more life ot of it. 5w30 will go through a worn engine pretty quick at
>>times. On more thing if you take this route, do change oil about every
>>2000 to 2500 miles or so as even though you are adding to it, it is
>>getting dirty faster and increasing wear potenail and oil consumption
>>too.
>>-----------------
>>TheSnoMan.com
>
>
> 180 psi doesn't seem like bad compression to me, what are the compression
> readings on all the cylinders? What are all the readings dry? and after
> adding oil through the plug openings to seal the rings? Have you done a
> compression leak down test? Dry and with oil added? Can you hear air
> leakage into intake or exhaust manifolds? Do any of the plugs indicate more
> oil fouling than the others? Have you tried any of the chemical ring
> cleaning procedures? Have you used a borescope to check the condition of
> the cylinder walls?
The psi readings were 215, 210,175, 205, from 1 to 4. Repeated
#3 and it went up to almost 180. This was a wet test.
Haven't done a leak down test and cannot hear any air leakage.
#3 plug, when removed looked fouled compared to the other 3,(
#1, #2, #4). Tried MMO soak, & it didn't do it. Don't own or
know anyone who has a borescope.

>
> Always make a teardown and rebuild your final and NOT initial strategy. I
> do agree that IF it is necessary to remove the head, then a head rebuild and
> inframe ring job should probably be done. Your oil consumption problems MAY
> be due to worn valve SEALS which CAN be replaced without removing the head.
>
> I agree with SnoMan that your first strategy to deal with excessive
> consumption should be to try different oil viscosities, (and change your
> shifting techniques to a less 'spirited' driving style). I also agree with
> reducing oil change intervals on engines with higher consumption rates. If
> cost is a major factor (or the difficulty getting at the filter if you do
> not have any ramps) then it is better to only change the filter every second
> change rather than to extend the oil change.
I am not a youngster and no spirited shifting is going on with
my Saturn. I would think that by biting the bullet now, the
engine, ie block, may not get totally destroyed and cost even
more to replace/repair.
>
> I would continue babying this engine with oil and viscosity and driving
> style changes until engine removal is necessary for clutch replacement. You
> can do a much better (and easier, and very importantly cleaner) rebuild with
> the engine removed.
I'm already babying this engine. The clutch is getting shaky at
120 k miles, and I did allow someone to relearn to drive to get
a license and the learner couldn't get the hang of my manual
shift Saturn.
>
> Re question #2, get local quotes for rebuild/valve job on your cylinder head
> from several automotive machine shops. They will normally check for warpage
> if asked, and will also check for valve stem/guide wear. Valve SEALS should
> always be replaced, your machine shop/rebuilder may have the equipment to
> install a better than OEM type of valve seal.
>
What valve seals are better than OEM Saturns?

BläBlä wrote:

> In article <B6GHg.468697$IK3.446143@pd7tw1no>, er
> says...
>
>>
>>180 psi doesn't seem like bad compression to me, what are the compression
>>readings on all the cylinders? What are all the readings dry? and after
>>adding oil through the plug openings to seal the rings? Have you done a
>>compression leak down test? Dry and with oil added? Can you hear air
>>leakage into intake or exhaust manifolds? Do any of the plugs indicate more
>>oil fouling than the others? Have you tried any of the chemical ring
>>cleaning procedures? Have you used a borescope to check the condition of
>>the cylinder walls?
>
>
> Compression should be taken while hot btw.
It was.
>
> Normal compression is 185-205 psi
> Minimum is 180 psi
1st time got a 175psi reading on #3. Also, that plug was fouled
compared to all others.
>
> I still wouldnt bother taking that engine appart until ALL other methods
> are exhausted to reduce consuption. Hardly worth while IMO.
Too poor now to get any other vehicle. It's this car or hoof it.
Victim of our great 'new world order' economy.

"CBrooks" > wrote in message
...
> Am considering options with a 93 dohc that has one #3 cylinder running
> 180psi. Engine has 120k and has the oil loss problems, 1 qt per 500 miles.
> Am planning on doing an 'in-frame' rebuild with rings, hone, bearings,
> timing set, oil pump, valve job & seals, clutch(maybe), water pump. Might
> as well pull it, right?
>
> Anyway, questions I have a
> 1.) Where does one find a straight bar of steel in order to check the
> 'deck' & cylinder head for warpage?
>
> 2.) Is there any ball park numbers of machining costs for a shop to repair
> a cylinder head or bore cylinder sleeves as need be? Should valve guides
> normally be replaced?
>
> 3.) Are third party timing sets from ebay OK?

I won't comment on #2 or #3, but a straight bar of steel can be purchased in
the form of a metal ruler at Staples, OfficeMax, etc. If you want to get
fancy, buy a ground rod or bar at www.mcmaster.com. Delivery is sometimes
the same day from those folks. Just don't look around that site too much.
They carry just about EVERYTHING at somewhat decent to not-so-decent
prices - but make buying ANYTHING efficient and convenient.

Joe in Northern, NJ - V#8013-R

Currently Riding The "Mother Ship"

Ride a motorcycle in or near NJ?
http://tinyurl.com/5apkg
http://www.youthelate.com

"CBrooks" > wrote in message
news
> Private wrote:
>> "SnoMan" > wrote in message
>> ...
>>
>>>On Fri, 25 Aug 2006 05:22:45 GMT, CBrooks >
>>>wrote:
>>>
>>>
>>>>Am considering options with a 93 dohc that has one #3 cylinder
>>>>running 180psi. Engine has 120k and has the oil loss problems, 1
>>>>qt per 500 miles. Am planning on doing an 'in-frame' rebuild
>>>>with rings, hone, bearings, timing set, oil pump, valve job &
>>>>seals, clutch(maybe), water pump. Might as well pull it, right?
>>>>
>>>>Anyway, questions I have a
>>>>1.) Where does one find a straight bar of steel in order to
>>>>check the 'deck' & cylinder head for warpage?
>>>>
>>>>2.) Is there any ball park numbers of machining costs for a shop
>>>>to repair a cylinder head or bore cylinder sleeves as need be?
>>>>Should valve guides normally be replaced?
>>>>
>>>>3.) Are third party timing sets from ebay OK?
>>>
>>>
>>>On the head warpage I would take the head to a shop and have it
>>>checked with you get a valve job done on it. On the oil consumption,
>>>it is not realy that bad and if it runs well otherwise I would switch
>>>to 10w30 in winter and maybe 15w40 (not 10w40) in summer and stop
>>>using 5w30 you will likely cut oil consumption in half or more and get
>>>more life ot of it. 5w30 will go through a worn engine pretty quick at
>>>times. On more thing if you take this route, do change oil about every
>>>2000 to 2500 miles or so as even though you are adding to it, it is
>>>getting dirty faster and increasing wear potenail and oil consumption
>>>too.
>>>-----------------
>>>TheSnoMan.com
>>
>>
>> 180 psi doesn't seem like bad compression to me, what are the compression
>> readings on all the cylinders? What are all the readings dry? and after
>> adding oil through the plug openings to seal the rings? Have you done a
>> compression leak down test? Dry and with oil added? Can you hear air
>> leakage into intake or exhaust manifolds? Do any of the plugs indicate
>> more oil fouling than the others? Have you tried any of the chemical
>> ring cleaning procedures? Have you used a borescope to check the
>> condition of the cylinder walls?
> The psi readings were 215, 210,175, 205, from 1 to 4. Repeated #3 and it
> went up to almost 180. This was a wet test.

Do a dry test followed by a wet test. An increase when wet indicates ring
leakage which is sealed by the added oil, most engines will show some
increase when wet. If there is little change when wet then this indicates
that the valves are the limiting factor. If the three good cylinders
increase when wet but the low cylinder does not then this would be a good
indication of a bad valve in that cylinder (or perhaps less likely, a gasket
or similar problem). In the event that there is a scored #3 cylinder I
would try that cylinder again after wetting with a heavy oil to see if that
made any difference as a heavy oil may fill the score enough to raise the
compression, but a borescope is better for this as you can also inspect the
wall for crosshatch and the color of the wall between the top rings can
indicate how effectively each ring is sealing.

Based on what you have reported, I suspect a valve problem in #3. A
leakdown test or even just applying shop air pressure to the cylinder (using
an 'air hold' fitting in the plug hole, which can be purchased or fabricated
from a spark plug by a welder) may allow you to hear leakage into the intake
or exhaust manifold (or both).

If the bad valve is on the intake side it may show as small rapid
fluctuations in a vacuum gauge connected to the intake plenum but a burned
valve is more likely on the exhaust side. which can sometimes be heard as a
roughness or popping in the exhaust but this is doubtful as the sound must
make it through the catalytic converter and the muffler..

One of the downside of 4 valve engines is that they double your chances for
valve and seal failure.

> Haven't done a leak down test and cannot hear any air leakage. #3 plug,
> when removed looked fouled compared to the other 3,( #1, #2, #4). Tried
> MMO soak, & it didn't do it. Don't own or know anyone who has a borescope.

Many aviation mechanics and repair shops have borescopes and would allow you
to take a look inside if you pulled the plugs in their parking lot. (Offer
money, lunch or case of good beer.)

>> Always make a teardown and rebuild your final and NOT initial strategy.
>> I do agree that IF it is necessary to remove the head, then a head
>> rebuild and inframe ring job should probably be done. Your oil
>> consumption problems MAY be due to worn valve SEALS which CAN be replaced
>> without removing the head.
>>
>> I agree with SnoMan that your first strategy to deal with excessive
>> consumption should be to try different oil viscosities, (and change your
>> shifting techniques to a less 'spirited' driving style). I also agree
>> with reducing oil change intervals on engines with higher consumption
>> rates. If cost is a major factor (or the difficulty getting at the
>> filter if you do not have any ramps) then it is better to only change the
>> filter every second change rather than to extend the oil change.
> I am not a youngster and no spirited shifting is going on with my Saturn.
> I would think that by biting the bullet now, the engine, ie block, may not
> get totally destroyed and cost even more to replace/repair.

I mean no dissrespect, but as a 1cam (2400 rpm sweet spot) owner I feel that
many 2cam drivers use too high a shift point. I doubt that you are doing
any serious damage to the engine IF the low compression is caused by valve
leakage. A broken ring which is scoring the cylinder is another matter, but
if that is the case the damage is probably done already and only a borescope
will give you an answer. If the leakage is caused by a burned valve then it
will probably continue to get worse and the compression will continue to
drop.

Only you can make your personal cost effectivness decision regarding repair
and it depends to no small degree on your estimate of the remaining life of
the rest of the car. You do not have a lot of miles on the unit but some
would say it is getting a little old in years.

>> I would continue babying this engine with oil and viscosity and driving
>> style changes until engine removal is necessary for clutch replacement.
>> You can do a much better (and easier, and very importantly cleaner)
>> rebuild with the engine removed.
> I'm already babying this engine. The clutch is getting shaky at 120 k
> miles, and I did allow someone to relearn to drive to get a license and
> the learner couldn't get the hang of my manual shift Saturn.

The neccesity of a clutch replacement makes the engine rebuild timing
decision much easier. Once the engine is out of the car a ring and valve
job does not seem like such a big additional expense.

>> Re question #2, get local quotes for rebuild/valve job on your cylinder
>> head from several automotive machine shops. They will normally check for
>> warpage if asked, and will also check for valve stem/guide wear. Valve
>> SEALS should always be replaced, your machine shop/rebuilder may have the
>> equipment to install a better than OEM type of valve seal.
>>
> What valve seals are better than OEM Saturns?

AFAIK the OEM seals are of the rubber umbrella type. There is an
aftermarket wiping lip type seal (which I believe was originally mfg by
Perfect Circle and often called a PC valve seal) which requires machining
the top of the valve guide for installation. I have used these seals on SBC
but have no experience with Saturn head rebuilding. There are some
experienced racers here and some may reply, or you may wish to search this
group in Google groups or the forum at
http://www.saturnfans.com/forums/search.php or
http://www.saturnfans.com/forums/archive/index.php/

Rebuilt valve guides do make an engine run very smoothly and IMHO this is
worth doing right. Another downside of 4 valve engines is that the cost of
a valve job doubles.

You are doing the right thing by asking questions and doing a repair based
on a well thought out plan.

Good luck, YMMV

Private wrote:

> "BläBlä" . S!RCRE4P.C0M>
> wrote in message ...
>
>>In article <B6GHg.468697$IK3.446143@pd7tw1no>, er
>>says...
>>
>>>
>>>180 psi doesn't seem like bad compression to me, what are the compression
>>>readings on all the cylinders? What are all the readings dry? and after
>>>adding oil through the plug openings to seal the rings? Have you done a
>>>compression leak down test? Dry and with oil added? Can you hear air
>>>leakage into intake or exhaust manifolds? Do any of the plugs indicate
>>>more
>>>oil fouling than the others? Have you tried any of the chemical ring
>>>cleaning procedures? Have you used a borescope to check the condition of
>>>the cylinder walls?
>>
>>Compression should be taken while hot btw.
>>
>>Normal compression is 185-205 psi
>>Minimum is 180 psi
>>
>>I still wouldnt bother taking that engine appart until ALL other methods
>>are exhausted to reduce consuption. Hardly worth while IMO.
>
>
> I agree.
>
> IMHE there is a lot of variation between individual compression gauges and
> they are not what we would call 'calibrated'. Similarly there is a lot of
> variability due to the procedure used, and as you say, the motor should
> ideally be at operating temp, but the maximum compression obtained will
> still vary depending on outside air temp and altitude (density altitude for
> any pilots) and humidity and condition of starter and battery and whether
> all other plugs are removed and throttle position and oiled or non oiled
> cylinders. The number of strokes to pump to max is also another important
> and variable indicator. There are also other factors that may confuse a
> compression test like a plugged air filter or catalytic converter or loose
> muffler baffle.
>
> IMHO compression readings should be considered relative to each other and
> relative to other indicators like oil consumption rates and plug fouling and
> evidence of blowby like dirty PCV valves and dirty engine internal (and
> often external & underhood). They can be a good indicator for valve
> problems but are not a very good indicator of ring condition and often an
> engine with seized oil control rings will give great test results due to the
> amount of oil on the cylinder walls and compression rings.
>
> As always, YMMV
>
>
This car blew oil from day one. Everything is telling me that
this 120k mileage auto that has had oil problems from the get go
and is gotten considerably worse since is in need of some
serious rebuild work now or it's going to really fail altogether
and there I'll be, with a nearly worthless vehicle. By getting
the work done now, maybe the cost will be less than I fear and
will be able to drive a solid and dependable car once again, and
that gets great gas mileage compared to others. I've driven this
vehicle since early 1993 and I can tell it's really not well
anymore. If I could afford another great gas mileage vehicle
that would be guaranteed for at least 30k miles I'd do it if
would be less than a rebuild on this one. Between a rock and a
hard place.