New 427 smokes
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Joined: Nov 1999
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From: lantana,fl.
New 427 smokes
Well after only a few hundred miles, my new motor is smoking burning oil.
It's really bad after it sits over night, so I took it apart, intake and valve covers found oil in the intake valves. Checked for gasket leaks {ok}
Looked at the valve stem seals several that I could see were bad,out of round and pinched looking
This is the only part of the motor I didn't build,
bought the heads assembled. The seals are some new type don't remember the name supposed to be the best they have.
The parts are cheap enough like 20 bucks but it's the labor to change them that pisses me off.
What type of seal would you go with???
It's really bad after it sits over night, so I took it apart, intake and valve covers found oil in the intake valves. Checked for gasket leaks {ok}
Looked at the valve stem seals several that I could see were bad,out of round and pinched looking
This is the only part of the motor I didn't build,
bought the heads assembled. The seals are some new type don't remember the name supposed to be the best they have.The parts are cheap enough like 20 bucks but it's the labor to change them that pisses me off.
What type of seal would you go with???
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From: lantana,fl.
Originally Posted by big_G
Viton seals seem to be fine, but you need to find out why they failed. Check the cam lift. Make sure the valve spring retainer isn't hitting the top of the seal.
Ok found the name of the seals made by VTO "valve train only"
PC type seal made by dupont {fluoropolymer} material
Where can you but Viton seals??
I'l have to check for clearance issues.
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From: lantana,fl.
Originally Posted by MotorHead
Didn't he have a killer cam in that motor ?
Yes lift is 674/624. They set up the heads for me and it's their cam too!
I shouldn't have clearance issues but BIG G has a point that I should check out. How much clearance should there be when valve is opened.
That's going to be tough to see and check.
Le Mans Master
Joined: Jul 2005
Posts: 5,752
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From: Austin Texas
Those seals are teflon, and sometimes the guide boss has to be machined down to accept the teflon seal. Other types of seals may not fit. You can either use a thin "Checking" spring so you can see inside the spring or disassemble 1 spring, put white lithium grease on the bottom of the retainer and rotate the engine a few times. If any grease transfers, it's too close. I would think .050 in. clearance would be plenty.
of the retainer and rotate the engine a few times. If any grease transfers, it's too close. I would think .050 in. clearance would be plenty.
Team Owner
Joined: Apr 1999
Posts: 21,953
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Last year I installed brand new aluminum heads on my new 427 with a solid roller cam. The seals and springs were bad
With the help of a friend I replaced all the seals and valve springs to quality items while it was in the car. it's work to install air to the spark plug hole and compress high 500 pound open springs and install the keepers.
With the help of a friend I replaced all the seals and valve springs to quality items while it was in the car. it's work to install air to the spark plug hole and compress high 500 pound open springs and install the keepers.
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From: lantana,fl.
Originally Posted by gkull
Last year I installed brand new aluminum heads on my new 427 with a solid roller cam. The seals and springs were bad
With the help of a friend I replaced all the seals and valve springs to quality items while it was in the car. it's work to install air to the spark plug hole and compress high 500 pound open springs and install the keepers.
With the help of a friend I replaced all the seals and valve springs to quality items while it was in the car. it's work to install air to the spark plug hole and compress high 500 pound open springs and install the keepers.
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Melting Slicks
Joined: Apr 2000
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From: San Jose California
In addition to the above, I would check the valve stems to make sure they aren't bent. From personal experience, my 427 was burning oil too. The problem was found to be a leak in the intake gasket sucking oil from the lifter valley.
Chuck
Chuck
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From: lantana,fl.
Originally Posted by Chuck Harmon
In addition to the above, I would check the valve stems to make sure they aren't bent. From personal experience, my 427 was burning oil too. The problem was found to be a leak in the intake gasket sucking oil from the lifter valley.
Chuck
Chuck
Called the parts house where I bought all the parts from to verify that the right lenght valves were used, he confimed that they were, actually talked with the person who builds the heads. What I didn't want to tell him was that I ran the motor hot once, had a leak at the water pump temp got up to 250 for a few min. this was one of the first things he asked,says he uses these seals all the time only fail if motor overheats. So with that being said that and it happened I will blame know one but myself and just fix it. I won't let this happen again that's for sure,lessons to be learned.
Just seems that these seals are pretty sensitive to heat,I asked him to send me a different type along with the same ones installed now.
I'll see which ones I like better.
Instructor
Joined: Sep 2001
Posts: 208
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From: Grand Ledge MI
Originally Posted by 74droptop
I will blame know one but myself and just fix it. I won't let this happen again that's for sure,lessons to be learned.
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From: lantana,fl.
Originally Posted by 68ragtop
You da man. Very few nowadays will suck it up and fix it themselves. They find someone else to point their finger at and try and get a free lunch. Nice move buddy, you are a dying breed.
Thanks