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oil in cylinder

  • Thread starter Thread starter mustbereel
  • Start date Start date Sep 17, 2006

mustbereel

Member
May 6, 2005
318
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Escondido, CA
Sep 17, 2006
#1
  • Sep 17, 2006
  • #1
When I started my 65 Fastback project 17 months ago I pulled the then barely running 289 and set it aside in the garage. It's been sitting there until today when I tore it apart to see if I could use it in my 65 coupe.

The good news: The cylinders are std. bore and the bearings are all std. size. This appears to be an all original 289. It even has Ford main and rod bearings.

The bad news: cylinder #3 has a few oz. of oil in it and the whole combustion chamber is coated with oil. What is the likely cause of this?

Thanks,
Brad
 
B

brin0357

New Member
Jan 26, 2006
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0
Sep 17, 2006
#2
  • Sep 17, 2006
  • #2
Valve guides, seals, or rings/cylinder wall. When does it smoke while running? Startup only?
 

mustbereel

Member
May 6, 2005
318
0
17
Escondido, CA
Sep 17, 2006
#3
  • Sep 17, 2006
  • #3
oil

I only drove it a few times before pulling the engine so I don't remember when or even if it smoked. I'm hoping it's the valve guides or something else in the head because I want to reuse the block. I don't plan to reuse the heads.
 

Max Power

Active Member
Jul 31, 2003
1,774
1
36
St Paul
Sep 17, 2006
#4
  • Sep 17, 2006
  • #4
Your gonna have to go .010 over and get new pistons anyway, so the machine shop cam magnaflux the block to check for cracks. I am guessing a broken ring, or bad oil ring.
 

mustbereel

Member
May 6, 2005
318
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Escondido, CA
Sep 17, 2006
#5
  • Sep 17, 2006
  • #5
cylinder wear

The cylinders are very worn. I can feel a good ridge at the top and it seems offset. I just figured with the amount of oil in there it would most likely come from above. I haven't pulled the pistons out yet and they'll probably break with the ridge but it will be interesting to see what they look like. I'll definitely have the block mangafluxed.
 
T

truck90278

New Member
Jun 4, 2006
382
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Redondo Beach, CA
Sep 18, 2006
#6
  • Sep 18, 2006
  • #6
More than likely valve guides, or possibly a crack in the head. when you take the block and heads to your machine (assuming you want to reuse your heads) the first thing they will do is check the castings for cracks. they will mike your block to determine the amount of cylinder wall taper, which will tell you how much overbore is required. don't exceed .030"
 
T

truck90278

New Member
Jun 4, 2006
382
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Redondo Beach, CA
Sep 18, 2006
#7
  • Sep 18, 2006
  • #7
if you stsick with your stock heads, be sure and have the machine shop install GOOD valve stem seals such as PC seals, the head will have to be machined for them. Well worth the small amount of money
 
T

truck90278

New Member
Jun 4, 2006
382
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Redondo Beach, CA
Sep 18, 2006
#8
  • Sep 18, 2006
  • #8
if you stsick with your stock heads, be sure and have the machine shop install GOOD valve stem seals such as PC seals, the head will have to be machined for them. Well worth the small amount of money
 

mustbereel

Member
May 6, 2005
318
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17
Escondido, CA
Sep 18, 2006
#9
  • Sep 18, 2006
  • #9
heads

truck90278 said:
if you stsick with your stock heads, be sure and have the machine shop install GOOD valve stem seals such as PC seals, the head will have to be machined for them. Well worth the small amount of money
Click to expand...


I plan to go with aluminum heads so I'll probably just junk the originals. I'm taking the block in this week to be magnafluxed. If it's good I'll have it bored and I'll put a new rotating assembly in it.

Thanks for the responses,
Brad
 

Max Power

Active Member
Jul 31, 2003
1,774
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36
St Paul
Sep 19, 2006
#10
  • Sep 19, 2006
  • #10
It's rare that valve guide only effect one cylinder. They usually fail at a consistent rate from cylinder to cylinder, and they rarely couse an oil problem at the level your describe. Rings or head gasket would be my guess, with the possibility of something being cracked.
 

mustbereel

Member
May 6, 2005
318
0
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Escondido, CA
Sep 19, 2006
#11
  • Sep 19, 2006
  • #11
guides

Max Power said:
It's rare that valve guide only effect one cylinder. They usually fail at a consistent rate from cylinder to cylinder, and they rarely couse an oil problem at the level your describe. Rings or head gasket would be my guess, with the possibility of something being cracked.
Click to expand...

The one cylinder thing bothered me too. I would think the guides would wear more or less evenly. I will probably pop out the pistons tonight to see whats up with the rings.
 

mustbereel

Member
May 6, 2005
318
0
17
Escondido, CA
Sep 19, 2006
#12
  • Sep 19, 2006
  • #12
oil is from head.

Popped out the pistons today. The rings on the offending cylinder were intact and the bore is smooth. I decided to investigate the head and removed the valves. It looks like the oil is entering through the intake valve. Possibly the valve guide but since I'm not reusing the heads I'm not going to investigate further.

 

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Max Power

Active Member
Jul 31, 2003
1,774
1
36
St Paul
Sep 20, 2006
#13
  • Sep 20, 2006
  • #13
Wow, it sure does look like oil is entering from the intake side. Might be a crack, might be an intake gasket, might be the guide, although I have never seen 1 guide cause that much oil.
 
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