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So Did A Tune Up Last Night, Found Some Disturbing Things -

  • Thread starter Thread starter JenkinsBS
  • Start date Start date Jul 14, 2012
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JenkinsBS

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#1
  • Jul 14, 2012
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So upon changing the spark plugs, I noticed that they all looked fine, except for the ones that came from ...

Cylender 8 - Lots of oil on the plug, not really on the threads, more past the threads toward where the spark comes from

Cylender 2 - Same as Cylender 8

Cylender 4 - Had a small amount of gunk / oil on it after the threads

Im pretty sure this means that I have ring issues in those cylenders? Anyone who can shed more light, would be appreciated
 

LilBerx

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Jan 11, 2012
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Jul 14, 2012
#2
  • Jul 14, 2012
  • #2
I see in your sig that your car is an 86?
I had the same problem in #8, I was getting massive oil buildup. I thought it was a bad ring. But I was running gt40 heads, and with the 86 bottom end they come with flat top pistons with no valve reliefs...

I ended up having a bent valve. Id scope out the inside of the heads before ruling it bad rings.
 

JenkinsBS

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#3
  • Jul 14, 2012
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To check for a bent valve, this would mean just taking off the valve cover / roller rockers to pull the rod?

If the person that rebuilt the motor (tweaker), is it possible he could have just adjusted my hydraulic lifter/valves too tight, causing those others to bend too, causing my issue?

And yes they are definatly flat top pistons.

Another issue that I am running into, which I know has been addressed, but figure i may as well ask here too - But the cars drivability is fine, it idles great, accelerates great, climbs in RPMs great, however when pressing the gas pedal to the floor (not just slamming on it from a dead stop), but just normal dirving, say 2nd gear, going 3k rpm (what i call, "the ready to romp zone"), and then slam it to the floor, it just bogs and stalls. Kicks forward and back until im off the gas. I am able to slam it to about 3/4 down without any issues, and she gets up and goes, but the WOT issue worries me. Any ideas on that?
 

ID89GT

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Jul 14, 2012
#4
  • Jul 14, 2012
  • #4
Do some compression testing and leakdown testing to verify what the problem is
 
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stykthyn

I want to measure mine. It doesn't look that tall.
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#5
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I would hold off on any more WOT runs until you figure out if your valve train is in good order.
 

JenkinsBS

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ID89GT said:
Do some compression testing and leakdown testing to verify what the problem is
Click to expand...

For leakdown and compression testing (im very limited on tools), i would just take it to my local ford dealership or trusted local shop?
 

a91what

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When is the last time the heads recieved new valve stem seals? if it has been a long time chances are you might have a few seals leaking allowing oil into the cylinder, cheap oil seals leak. This is a problem i have run into on old engines, i have a brand new shortblock with stock heads slapped in place while i wait for aluminum ones. i too have some oil on my plugs as long as it is not blowing smoke you should be ok. and yes i am very sure i have no ring issues.
 

a91what

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#8
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I didnt see the WOT issue before you may want to take her to a shop for more testing.
 

JenkinsBS

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Trying to do it on a budget is a pain in my ass - but its looking like ill have to talk to some people i work with that have connections to our local ford dealer, see if i can manage to not get ripped off
 

stykthyn

I want to measure mine. It doesn't look that tall.
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Did you check piston to valve clearance when you installed the heads.without valve reliefs you likely bent at least one valve.
 

a91what

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When you stomp it down does it blow any smoke?
As far as the compression testing tools you can borrow them from advanced auto, i do this often. test the cylinders that you saw oil in first but do them all. It is relativly easy to do and will tell you if you have a bent valve. I would start with this if money is a concern as you can do it yourself. once we get that info we can help you further.
 

JenkinsBS

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a91what - The last time the heads have had new valve seals was when it was rebuilt (7 years ago maybe, and NO, the tranny was not rebuilt or cleaned, so thats all just crap from years of buildup), however the car was not fired up and ran until june 2011; To your second question, if it blows smoke when I stomp on it, it blows, well, yes I guess it is smoke, but ill let you be the judge; Is that an abmoral amount of vapor coming from the tail pipes?- http://youtu.be/Un9H2BqIvW0

Stykthyn - I had a shop put this together, and they were a pretty shady place, so I do not know if they did.

NOW - another side note, the car leaks some oil (what car doesnt, haha) but what worries me is where this is coming from. It was NOT this bad before I did my oil change (still using 10w 30), and what im afraid of is it might be the rear main seal. Could it be coming from the back of the lower intake manifold?

The splat on the ground in the second picture is about half the size of a DVD or CD, so, quite a bit, and you can see its coming from between the



 

a91what

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ok your oil leak is likely the rearmain seal... mine leaks too. How often do you have to put oil in the car? if you have to add oil between changes then it is a bad leak.
Does it always blow that much smoke? i ask cuz mine smokes on startup before i clear it out, it does this because as it sits oil runs down the bad oil seals. Once the engine is cleared out and warmed up it should NOT smoke like that.
*I still suggest doing a compression and leak down test as this is the only way to ensure you dont have a bent valve. If the heads need to come off the car, we can walk you thru it so you can save some money. A chiltons manual will prove helpful they are 25 bucks at advanced and i use for reference often, it has step by step instructions for break down and reassembly.
 

JenkinsBS

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I do need to add oil inbetween oil changes, not too much though - but I will keep a closer eye on it now as to how much I add and how frequently now, but I think its a bad leak...

During that video, I took the car to a friends house which is about 2 minutes away, so it was not really that warm - however I have had people tell me that when I rev it hard (after a long drive), that it still smokes, just trying to determine if that is oil that is burning out, or if its gas.

Now I am at an impass - I bought 30# injectors and put them on the car with a 75mm calibrated MAF a while back in anticipation of boosting it, and was contemplating putting some stock 19#s back in with the stock MAF, but thats if im buring fuel (it does smell rich)

But if the "rich" exhaust smell is coming from oil buring from inside the engine, AND the rear main is leaking, I may as well start a fund and rebuild the whole thing again, but have it done by a reputable place, cause I def dont have the tools to pull the motor again, or a stand, or a pull...
 

a91what

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rich smells happen, if it has deleted cats it will smell, if the charcoal filter is bad it will smell, the fuel pressure regulator can be bad, ect....what did the good plugs look like? (a cocoa color is what your looking for)
Burning oil and rich do not smell anything alike. You need to do a compression test first before you assume the engine is shot. pulling the heads is easy and you can get all the tools you need at harbor frieght for almost nothing. The rearmain seal can be done with the engine in the car.... just drop the tranny and remove the flywheel its right there. 24 bolts, two electrical connectors, speedo cable, tv cable, and shifter cable. youll need two jack stands a floor jack a piece of wood and a friend. oh and patience
 

JenkinsBS

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ive got both the chiltons and haynes manuals, i think my problem is going to be having a place to do it, i live an an appartment complex.

To drop the transmission, you have to drain the oil first right?


**edit** checks haynes manual
 

JenkinsBS

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#17
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is it possible to keep the driveline connected to the rear end while doing this?
 

stykthyn

I want to measure mine. It doesn't look that tall.
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Drivel shaft has to come out.well at least unhooked from the rear end. No you don't have to drain it, but make sure you leave the drive shaft in the tail housing so you don't lose your fluid. As for the engine i would source some used e6 heads. A head swap isn't that much from a parts stand point and i doubt you will notice a difference in performance with the issues you are having.
 

a91what

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he is running ported e7's the change to e6's may fix his ptv issue's ( if any exist). The e6 heads can be found for almost nothing. I had a set but used them for porting practice.
The driveshaft has 4 bolts attaching it too the rearend. Put the front of the car on jack stands, chalk the rear tires, set the e brake, using a grease pencil or chalk mark a line to ensure you bolt it back up in the same place. remove the first bolt, shift to neutral turn the driveshaft then put it back into gear and hit the next bolt, repeat.
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
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a91what said:
ok your oil leak is likely the rearmain seal... mine leaks too.
Click to expand...

--or--:



That oil appears to be coming from outside of the bell housing. Rear main leak would come from inside. Can't rule it out on this picture alone but the inside lip appears to be clean. Your leak looks to me like it's a lower plenum leak. Get a look behind the motor with an inspection mirror and see if you have oil running down the backside of the heads before pulling everything apart to replace the rear main seal.


Oh... There's no way in hell I'd go the dealership for a compression and leak down test. Find a local mechanic in your area. The tests themselves are not rocket science.
 
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