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My '72 2000 GTV has 30% leak down in #3 cylinder, with the apparent culprit being the exhaust valve guide. Temp check of the headers as the engine warms up shows #3 consistently 20-30 degrees below the others. Pistons are stock but hi-lift cams were installed back in the '90's by previous owner.

Q1-Should I go ahead and get the valve job done now to correct this problem? What is downside of driving it this way to failure or until leak down is greater? Q2-How difficult is it to pull the head and take it to someone for rebuild as opposed to paying someone to do it? I am reasonably good mechanic, but no experience w/Alfa engine work. Q3-What should I expect to pay for a complete valve job at an experienced Alfa shop? I am in SF Bay Area, so lots of options out there.

Thank you for your help...always appreciate the collective knowledge of this club!
 

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A little shot of inspiration, Steve.

I removed the cylinder head myself and had a shop do the necessary machine work. Working slowly, It went back together well, I adjusted the valves, cams and it started right up. Overall, it was a rewarding experience.

If you're interested in getting involved with the inner workings of your car, go for it. If not, then consider choosing a shop.


--Doug
 

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Richard Jemison
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Issue

My '72 2000 GTV has 30% leak down in #3 cylinder, with the apparent culprit being the exhaust valve guide. Temp check of the headers as the engine warms up shows #3 consistently 20-30 degrees below the others. Pistons are stock but hi-lift cams were installed back in the '90's by previous owner.
Well, maybe a valve issue, but not a valve guide issue.

But to correct any "Valve" issue it will require replacing valves, and guides. If "high lift cams" (12mm or over), you should use short guides, green viton seals in the rebuild.

The "short guides" are available from Centerline as the 3.0 V6 12V exhaust guids.
 

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In the Bay Area, Norman Racing is a good place to have the head work done. Typically $800-1200, depending on what's needed. That doesn't include R&R of the head.

Andrew
 

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My '72 2000 GTV has 30% leak down in #3 cylinder, with the apparent culprit being the exhaust valve guide.
I wouldn't have responded before Richard, but he confirmed my suspicion. Low compression would be the result of worn/burned valves, not worn valve guides.

Andrew's numbers ($800-1200) are as good an estimate as any before the head is removed and the actual situation is assessed. If your existing valves and seats can be re-ground, you're at the lower end of the estimate. If the valves/seats are worn/burned beyond repair, think the higher end. Going to an Alfa specialist (like Jon Norman) is a good idea. A Toyota/Honda/Nissan shop will probably screw it up.

carsteve said:
How difficult is it to pull the head and take it to someone for rebuild as opposed to paying someone to do it?
On a scale of one to ten, it's a 7.248.

All kidding aside, lots has been written on the BB about head removal and replacement procedures. You will save quite a bit of money and learn a lot about your Alfa by doing it yourself. Also, you will probably do a better job and can chose which machine shop to send the head to. But yes, it will take a few hours.
 

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Going to an Alfa specialist (like Jon Norman) is a good idea.
Going to John Norman is a very good idea. I once took a head to a guy who was an Alfa specialist and he did a "performance" job with very narrow seating area on the exhaust seats which resulted in early valve failure.
 

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The alfa heads are pretty simple. I did this having never done it before. I pulled the heads, cams, etc but sent the stripped head out to have the deck checked for flatness, deep cleaned, guides pressed out/in and have the valves lapped in to seat right. Believe it or not i paid $290. I assembled everything myself.
 

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I will recommend getting a good valve spring compressor (C-type) WITH a little adapter to seat it on the keeper. I used a craftsman compressor, which was fine, but it kept slipping and my home made PVC pipe adapter left a whole lot to be desired. These guys should set you straight. Cylinder Head Supply
 

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Thanks to all who responded. Particular appreciation to Vintre for posting step by step pics...I'm always amazed that folks are willing to so thoroughly document and graciously share their experiences. Really helps to SEE it done. With that guidance and all the encouragement, I am going to tackle the removal and reinstallation myself, with Jon Norman's outfit doing the head work. Thanks again...I'll let interested parties know how it comes out!
 

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If "high lift cams" (12mm or over), you should use short guides, green viton seals in the rebuild.

The "short guides" are available from Centerline as the 3.0 V6 12V exhaust guids.
Not just short guides, but a deeper press (see Motronic engine specs for example). And the problem starts already at 11mm lift. Guess how I know :D
 

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Your Alfa engine is a lovely thing to work on. I remember when I first pulled the head from a GTV (circa 1985), my local gurus reminder me to keep the shop and engine pieces clean, clean, clean; they also reminded me to be gentle with aluminum pieces (me having come from an MG and Triumph -cast iron- background at that stage of life). Take good notes and photos of how the FI pipes to injectors are fastened...very important to prevent them from cracking later due to vibration. If the head is stuck, you can easily make a puller with a thick steel plate (although i used a stout piece of oak) and a spark plug thread welded to some threaded rod. One benefit to just taking the head complete to Norman is that they can properly set the valve clearances for you. That's still the way I do it. Enjoy the job and kind regards, John in CT.
 

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Doing this yourself ranks right up there with seeing your child ride that first time sans training wheels. Take your time, enjoy!
 

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Thanks to all who responded. Particular appreciation to Vintre for posting step by step pics...I'm always amazed that folks are willing to so thoroughly document and graciously share their experiences. Really helps to SEE it done. With that guidance and all the encouragement, I am going to tackle the removal and reinstallation myself, with Jon Norman's outfit doing the head work. Thanks again...I'll let interested parties know how it comes out!
Keep us posted on how you are getting on with it. Lots and lots of pictures!
 
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