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74 GTV 76 Alfetta GT
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Discussion Starter #1
Any tips on valve guide seals for the 2.0l head would be appreciated.
My machinist is having a heck of a time installing the green oe seals from both Centerline and Classic Alfa. He says the ID is too small on the guide end of the seal.
The old seals are white teflon and I'm beginning to suspect they might be what Centerline sells to fit their guides. Is there a standard guide size to these heads? Or does each suppliers have their own guides and seals?
 

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White teflon seals are for different guides I believe that centerline sells. Stock seals wont fit. Good luck
 

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Green seals are correct for stock guides. The way to set them (head off) is with a bolt, 2 washers and a nut. Pass the bolt thru, add the washer, and tighten down, forcing the seal onto the valve guide
 

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74 GTV 76 Alfetta GT
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Discussion Starter #4
Thanks for the tips! I will mention this to the machinist.
 

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Richard Jemison
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White Teflon seals are too tall for high lift cam clearance. With Centerlines short guides (Pt # VG 245 and Green Reintz seals Pt # VG 191 they fit fine. But they don`t push on, you have to have a seal installer tool.
You must not be using a knowledgeable Alfa mechanic....
 

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74 GTV 76 Alfetta GT
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Discussion Starter #6
He showed me a piece of pipe that he machined to install the seals. Is this the seal installer tool?
 

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The way I do is put a heat shrink sleeve on a bolt so it doesnt scratch the inside of the valve guide, Add a washer, pass it thru with the head of the bolt inside (facing cylinder), pass it tegu the seal, add a washer and a nut, and tighten it down to draw the seal on. Pretty simple and I’ve never ruined a seal doing it that way
 
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74 GTV 76 Alfetta GT
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Discussion Starter #9 (Edited)
Looks like this head has a mix of 2 different guides.
I'm guessing the top one is original and the bottom one is one is newer?
The exhaust side has the the bottom pic guides. The intake has 3 guides shown in the top pic and one in the bottom pic.
PXL_20201127_144742866.jpg
PXL_20201127_144728113.jpg
 

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74 GTV 76 Alfetta GT
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Discussion Starter #11
Thinking out loud here but Im wondering if the exhaust guides wear faster since it's hotter on that side compared to the intake side. That might explain why the newer guides are on the exhaust side.

On another note my machinist got 7 teflon seals on and 1 green seal on :/
He said one guide had a better fit with the green seal.
I'm not thrilled about this and thinking I'll take the teflon seals off and install all green seals with the bolt method goats recommend. Dumb idea?
 

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The seals will not inter change with the different guides. The proper way would be to replace the guides and use the same type on the intake side. Also can install guides to use seals on the exhaust as well... like the later engines. Good luck
 

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Richard Jemison
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ALL GUIDES DO NOT HAVE THE SAME SEAL AREA, DESIGN&DIAMETER. IT APPEARS YOU GOT THE NON FACTORY TYPE GUIDES THAT WILL ONLY FIT THE TALL TEFLON GUIDES.

Not yelling, Cap Lock was on...
 

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Discussion Starter #14 (Edited)
Ideally I'd like to have all the same guides and seals in this head but my machinist already did the work.

Richard I believe you are correct that the newer guides in this head require the teflon seals.
Would it be wise to install the green seals on the remaining original guides?
I'm guessing one original guide got the one green seal. I'll double check this with my machinist.

This is one heck of a puzzle and if I'd known better I would have gotten all new guides and matching seals to my machinist.
 

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Richard Jemison
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The better choice would have been finding a shop specializing in Alfa.
As it is as long as you are using stock lift cams it should be fine. Larger lifts will be a problem.
 

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Discussion Starter #16 (Edited)
Is there a way to measure the collet to seal clearance to get an idea of a safety margin?
I'd like to use something like a euro 10548 cam but if clearance is a problem I'll stick to the stock cams.
 

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Discussion Starter #18 (Edited)
I pulled the valve springs off and sure enough the teflon seals fit the newer guides and the Viton green seals fit the old guides.
As suspected there were 2 teflon seals where Viton seals should have been.
What a mess, and a lesson learned!
 

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Discussion Starter #19
A big cheers to everyone helping me get through this!
 
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