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Topic: Great, another oil leak SOMEWHERE! (Read 1861 times) previous topic - next topic

Great, another oil leak SOMEWHERE!

I've got a pretty substantial oil leak on the driver's side.  I can't really pin it down so I need some ideas.  The exhaust manifold is covered in oil and smokes like none other at stop lights.  What's the first thing to check?
1987 Thunderbird 3.8. Sold :(

1982 Thunderbird - Goodbye 255, Hello 302!

Re: Great, another oil leak SOMEWHERE!

Reply #1
First thought would be valve cover, they ll tend to leak on these cars. :D
95 Ranger Splash 2.3
88 Tbird Sport :ies::ies:
5.0 SO, stainless shorty headers, w/ Magnaflow lers. KYB struts, KYB shocks. 5lug conversion from sn95 Mustang, subframe connectors, drilled and slotted rotors, 03 Mach 1 wheels. sequential taillights.140 speedo

Re: Great, another oil leak SOMEWHERE!

Reply #2
Exactly what it sound like to me. Its ok the rear gasket on my intake leaks along with a trans line fitting and other various parts that hold fluids.
85 Tbird 5.0
78 F150 351w
13 F150 4x4 3.5 Ecoboost

Re: Great, another oil leak SOMEWHERE!

Reply #3
Agreed.
The valve covers leaked like crazy on my '86 3.8. I bought some gaskets for 'em but wrecked the car before I could put 'em on.

They're actually in my thread in the for sale forum right now...
:D
[SIGPIC][/SIGPIC]

Re: Great, another oil leak SOMEWHERE!

Reply #4
Yea check the valve cover gaskets. Should be really easy to change since you have an 87 Bird with cfi.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Re: Great, another oil leak SOMEWHERE!

Reply #5
drivers side on the 87 3.8 is easy, passanger side isnt the most fun thing to do
It's Gumby's fault.

Re: Great, another oil leak SOMEWHERE!

Reply #6
Quote from: cougarcragar
Agreed.
The valve covers leaked like crazy on my '86 3.8. I bought some gaskets for 'em but wrecked the car before I could put 'em on.

They're actually in my thread in the for sale forum right now...
:D


I'll get the gaskets replaced then.  You have a pm.
1987 Thunderbird 3.8. Sold :(

1982 Thunderbird - Goodbye 255, Hello 302!

Re: Great, another oil leak SOMEWHERE!

Reply #7
the reason why valve covers leak is because people dont notice the  attention to detail required.  The bolts get cranked down from time to time by the owner.  after a while, the bolt holes in the cover will ***bevel*** downwards. Since the metal around the hole bevels downwards,, the the cover will bottom out to the head sooner. This makes you think you require a thicker than normal valve cover gasket.

the fix..............

inspect each hole on the cover and the downward bevel.
Flip valve cover upside down and lay its flat edge on a 2x4
tap on each hole with a flat metal object and a hammer
after holes are flattened, the gasket should be smooshed evenly when installed
it would be ideal to bevel the holes upwards slightly so more presure is put on the entire gasket

Prevention...........
check out the bone yard and you will find some GM engines have a "wing" shaped washer on each bolt hole. Find you some of these and install them. You wont need to fix the cover again cause the wing shaped washer covers a distance of about an 1 1/2 inches on either side of each bolt/hole while increasing your presure more evenly around the cover.
You could just make you a set like i did.  I found me a frame work braket inside a microwave and decided to keep it for something one day.  I hacksawed the basic shape and drilled the hole out then touched up with the bench grinder. I sprayed flat black on them and called it good.


Installation.............
technically speaking, you should not need gasket sealer ,, its your choice.
Install and snug the bolts
Insure that the bottom three bolts get the most attention and snug down the top ones.

on your problem,,,,,,,,use carb cleaner and spray off the front side of the intake and the forward and lower side of the valve cover.  Also spray around your external oil pump where it "necks" into the side of the timing cover.  Take it for a drive and monitor it every chance you get.  the leak will tell on itself from this point. 


here is the washer i mentioned,,,

Re: Great, another oil leak SOMEWHERE!

Reply #8
or just get a set of cast aluminum covers... :tg:  ;)
95 Ranger Splash 2.3
88 Tbird Sport :ies::ies:
5.0 SO, stainless shorty headers, w/ Magnaflow lers. KYB struts, KYB shocks. 5lug conversion from sn95 Mustang, subframe connectors, drilled and slotted rotors, 03 Mach 1 wheels. sequential taillights.140 speedo

Re: Great, another oil leak SOMEWHERE!

Reply #9
yeah I thought that they were supposed to leak at lights.... My v-6 is the only one that dosent now.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Re: Great, another oil leak SOMEWHERE!

Reply #10
Quote from: cougarman
or just get a set of cast aluminum covers... :tg:  ;)

try to find some for an early 3.8L

all i found was chrome stamped steel ones
It's Gumby's fault.

 

Re: Great, another oil leak SOMEWHERE!

Reply #11
I switched from plastic v/c to the metal type.  Installed cork gaskets and torqued to 36-61 In Lbs.  Problem solved.  Next leak was at rear of intake and would run down bellhousing and then auto trans lines.  Fixed intake leak and presto, dry motor.  My sisters car ('85 LTD 3.8L) leaks at the intake and I'm still trying to get the nerve to fix.  On my race car I can see the bellhousing, on the LTD I can't, because of all the a/c and other s**t.    Good luck,  Fred

Re: Great, another oil leak SOMEWHERE!

Reply #12
Okay, it turns out I'm just retarded...  I left the dipstick out just a little bit, which accounts for the oil under the hood, but I also discovered the oil is really watery and I'm adding coolant fairly often which leads me to the conclusion that I have to undertake the dreaded headgasket job.  Anyone care to walk me through it?  Skill level/tools required?  What am I going to have to take off?
1987 Thunderbird 3.8. Sold :(

1982 Thunderbird - Goodbye 255, Hello 302!

Re: Great, another oil leak SOMEWHERE!

Reply #13
Head Gasket Remove (3.8 specific but applies in general)

purchase list
Felpro headgasket kit
Felpro TTY bolts (torque to yield)
CFI base plate gasket kit (not actually optional but its up to You)
lifters (cheap so just get them)
valve job (optional)

skill level required (anyone who wants to give it a try)

steps to remove/replace

Number each connection with tape
example:
PCV fitting on rear of cfi will have a number "1" as well as a number "1" on the actual line.  this allows you to mate up connections easier later on if your project gets stalled.
take a couple digital photos of several angles of the engine bay


unplug wiring harness(s) to pretty much everything on the top of engine
undo plug wires (number them)
drain most of the radiator fluid via the wing nut on radiator
undo vac lines to rear intake/egr/pre heat valve
unconnect heater / radiator hoses
remove valve covers
remove all your rockers/pushrods
pattern them so they go back where they came from
loosen up exhaust header bolts under the car where the meet the y pipe
remove exhaust bolts
remove cfi egr base plate
remove intake preheat valve bolts on driver side intake
rotate the preheat valve to access intake bolts
remove all intake bolts
lift intake off
remove head bolts
pry off heads
locate alignment dowels (hollow tubes)
install your dowels in the engine side if you can remove them
sometimes the dowels will stay on the engine and sometimes on the head or both.
clean off surface of block and head with putty knive
sand it with what ever you can come up with but get it real clean
stand a straight edge up on its edge from opposite corners of the head measuring diagonally.
shine a light in the background
use a feeler guage to measure warpage (.006 allowed)
measure warpage from side to side or withdth (.003 allowed)
*even brand new heads have warpage in the center***
you will find your warpage to be concentrated in the center and thats normal.
*the warpage is taken out when head is installed due to torque pattern
*if you would like, mill the heads and get rid of the warpage all together

install headgaset but pay attention to the pattern of how the water jacket holes are.
some smaller water jacket holes are blocked off or slightly blocked off due to how the gasket is made.
feel free to enlarge the "TRIANGLE" holes in between the cylinders using a metal chissel if you like. Use a piece metal on the backside, not wood.  Wood gives and it will bend your gasket.  The headgasket is pre stamped holes are normally to small and i consider this a water restriction.
clean off surfaces and add your gasket to the engine block
use your new bolts and snug down the bolts on the head working from the center outwards in a criss cross pattern.  Snug means snug, not tighten.
You will want to snug them down about three trips all the way around. 
torque to about 20ft/lbs on the first tightening sequence then to factory specs on the final go around.
***the key here is to work from the center moving outwards in a criss cross pattern.  This takes out the warpage in the center.

No sealer needed

when you get the heads on, just simply tighten the rockers / pushrods to about 20ft/lbs.
you will leave the valve covers off on your initial start and tweek in any noisy rocker arm anyway.
No, the oil wont fly around if you tuck a towel in between the plug wires and the heads along each head.
install everything in reverse order and look for leaks afterwards.

i hope i didnt forget anything



------------------------
some instances will require the distributor to be removed so here is that part as well

locate and mentally note where cylinder number one plug wire is located on the distributor cap (should already be a "1" on it)
remove distributor cap only
rotate crank shaft with breaker bar till harmonic pointer is on the "0" degree mark
does the rotor button point in the general direction of where Number 1 plug wire was?
if it appears that is 180 degrees off or pointing the opposite, rotate the crank shaft again one full turn and get it back on zero degrees top dead center
now your rotor should be pointing to number 1 plug wire post on your distributor cap
to verify your on TDC combution stroke , remove number one plug
insert a screwdriver in the hole and you will feel the piston is up top
also note that both intake and exhaust valves are not pushed down
there will be a little play in both rockers
this confirms there is no tension on the pushrods and the piston is up.
dont rotate anything anymore,,, dont touch,, just dont!!
mark the edge of the dissy where the pointer is aimed.  Your mark should be placed on the surface where the cap would normally sit.
follow the dizzy shaft down to where it inserts into the timing cover
clean off grease
make a stright line mark on the base of the dizzy and on the timing cover
remove dizzy holding bolt/clamp (1/2'' or 13mm)
remove dizzy but be very slow
rotate the rotor button CCW as you lift upwards
if your oil pump shaft comes out, Live with it and deal with it later, just dont drop it inside the timing cover.
reinstall your oil pump shaft
get a long piece of vac hose and slip it just slightly over the end of the oil pump shaft
slowly lower the shaft into the dizzy hole until you have landed the end into the oil pump gear "HEX" opening
rotate the vac hose cw or ccw to loosen the hose fromt the shaft
dont lift up as you do this , just rotate it slowly and it will release.

wheeww,, that was the tricky part

Re: Great, another oil leak SOMEWHERE!

Reply #14
Thanks for the write up!  I'll keep it for future reference.  I'm pretty sure I'll be getting a new motor (3,000 miles on a rebuilt one).  I'm getting some serious blow-by and the oil pan and rear main are leaking.  The list goes on and on.  A rebuild was probably in order eventually and I'd rather not spend the cash on one repair at a time when I can start fresh with a new engine.
1987 Thunderbird 3.8. Sold :(

1982 Thunderbird - Goodbye 255, Hello 302!