Possible Valve Job

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bigfoot72

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Hello Everyone,

So i'm guessing that my car needs a valve job but i'm not completely sure. 

Some of the signs i've noticed are rough idle when the transmission is in drive, but neutral seems to smooth it out. Also some smoke from the exhaust. One of the alternator bolts snapped and i have a feeling it was due to the engine shaking. Anyone know what this problem could be? Advice would be very appreciated. 

Thanks guys,

-Zak

 

bigfoot72

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Hello Everyone,

So i'm guessing that my car needs a valve job but i'm not completely sure. 

Some of the signs i've noticed are rough idle when the transmission is in drive, but neutral seems to smooth it out. Also some smoke from the exhaust. One of the alternator bolts snapped and i have a feeling it was due to the engine shaking. Anyone know what this problem could be? Advice would be very appreciated. 

Thanks guys,

-Zak
Oh and my car is a 1972 Ford Mustang with a 351C-2V.

 
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What color is the exhaust smoke? Bluish/gray is oil, black/dark gray is unburned fuel, white is water vapor. Oil burning indicates more problems than just needing a valve job. Water vapor that doesn't go away after engine is warmed up also indicates potential problems. Unburned fuel could be carburetor or ignition problems, also badly burned or recessed exhaust valves.

 
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It does sound like it could be a vacuum leak, also you might need to replace your valve stem seals because they become brittle with age and end up in the oil pan causing the oil pump to lock up.

 

piper62j

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Dark grey or black smoke indicates a rich fuel mixture.. Light grey smoke is oil burning.. If there is a puff of light grey smoke at start up, that indicates defective valve seals.. Light grey smoke emitted all the time, or when the engine is under power indicates worn piston oil rings.

Test for a vacuum leak first.. I spray brake cleaner (the new type) around the base of the carburetor, along the intake manifold bolts, egr valve, and all vacuum hoses, even up at the power brake booster with the engine at idle.. If you notice a change in engine rpm, the area you sprayed last is where the vacuum leak is.

A compression test will tell you a lot also. There are two types. Compression and leak down..

Pick up a cheap Ford repair manual (usually a flea market or at the local library) which will give you the specs on all the above testing..

Lastly, you may want to inspect the distributor points (if you have them), dirty spark plugs fouled with oil and the voltage output on the secondary side of the ignition coil. All these can add up to poor performance.. A stuck pcv valve will wreak havoc too by sucking too much oil vapor from the valve cover.

The broken alternator bolt is the result of over torquing, not engine vibration. There should have been a spacer between the alternator and the bracket where it mounts to the cylinder head to spread the load.

 

delawarebill

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[url=https://ibb.co/nRVcVLd][img]https://i.ibb.co/yVMyMQv/side.png[/img][/url]

4Vforever

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http://www.alliedmotorparts.com/cylinder-heads/ford.html?id=7&category=%3F&make=16&model=792&year=42&engine=1031

if your engine is an orig '72 ck them out.. i just got a set from them and looked great.. free shipping to u and free return of your old heads. you can call them and ask if the heads are really a '71 or just a fit.. if u want to keep it stock.
All I can say is wow, $190 for a pair of "rebuilt" heads shipped and take your cores return for the same money. I have always and I like my stuff to be built to a quality not to a price. They're probably OK for a half worn standard engine, but to me for that price corners are cut somewhere. As the saying goes, good work ain't cheap and cheap work ain't good.

 

delawarebill

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[url=https://ibb.co/nRVcVLd][img]https://i.ibb.co/yVMyMQv/side.png[/img][/url]
forever, i sure hope that's not the case. but i was thinking the same as stated.. my old one's were beyond fixing.. well they could have been for $700 bucks.. when i received the new ones i did a visual check and they look very nice.. they do come with a year warranty.

 

bigfoot72

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What color is the exhaust smoke? Bluish/gray is oil, black/dark gray is unburned fuel, white is water vapor. Oil burning indicates more problems than just needing a valve job. Water vapor that doesn't go away after engine is warmed up also indicates potential problems. Unburned fuel could be carburetor or ignition problems, also badly burned or recessed exhaust valves.
It's kind of a mid/light gray.

 

bigfoot72

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piper62j

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There are other companies out there that sell reman / rebuilt heads.. I was very happy with AutoIweb.com.. Check out their video

 

4Vforever

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forever, i sure hope that's not the case. but i was thinking the same as stated.. my old one's were beyond fixing.. well they could have been for $700 bucks.. when i received the new ones i did a visual check and they look very nice.. they do come with a year warranty.
If your engine is pretty much on the standard side all shall be fine. If you seen some of the stuff that one shop I worked in for a very short time did for car yards, you'd be shocked a shop would do that sort of thing. Then again with second hand car yards, not much surprises me with those greedy sharks and spending as little as possible just to make a car run is what they do. I worked at that shop for less than two weeks but I could write a book on the BS I seen while there. In the end I just quit and told the owner I can't keep putting my name to that crap as it wasn't the way I learnt and walked out. To me anyway, my reputation is worth way more than a few dollars in my pocket.

 
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