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I've recently checked out a 70 XR7 that I'm interested in buying. The car is in good shape with only 65000 actual miles. The only problem I can tell is that it blows black smoke out of the exhaust when the car is started. The guy who owns it even has two black soot stains on his garage floor where the exhaust pipes blow. Any ideas on what is going on?? The engine is a 351W 2BBL. Some friends of mine think it needs a valve job. If this is the case does anyone have a ballpark figure on what a valve job would cost and if I need to go to a repair shop specializing in engines?? If anyone knows of a good engine shop in the Cleveland OH area I'd appreciate the referral. Thanks in advance - I've been cougarless for over a year and I really want to move on this.
 

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If the car is a nice car and at the right price don't let the smoke stop you from buying it, A valve job would set you back 200-400 dollars depending on the shop and probably under 200 if you do the labor and just take the heads to a machine shop. The problem is when you take the heads of you decide nows the time to do the timing chain, might as well upgrade that cam a little, gotta have an eldobrock and holley to top it off with and it can't breath with out those headers....damn I wish I would have bought those dart heads instead of doing the valve job.....Of course I have heard of these things happening but it has never happened in my garage....lmao
:1poke:
Seriously though, you could always just put valve seals in if it runs ok and doesn't miss at idle. A valve job isn't too bad to do, do it yourself and save a buck or trade your skills to someone who can do it for you.
John
wvcat
 

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you sure that the carb isnt running rich?? im not the best with mechanical work ( body and paint guy here :D ) but this is pretty much the system i use...... Black smoke rich mixtute Blueish smoke - burning oil ( in THAT case i would think its the valves or a head problem. or the oil valve seals ) white smoke ( smoke, not steam that all cars get when they are cold ) uh oh-- coolant getting in. possible bad head gasket or cracked head or block. i think you should tune the carb a bit and see what heppens. maybe do the jetting or just take some advice........... 4bbl it !!!!!!!!!!!!!!!!!!!!!!!!!!
 

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Farside, is the smoke present only when you start it? That could be a rich fuel mixture resulting from the choke operation. If the smoke is always present, even with the engine a operating temperature, then its running rich. But in either case, it's no big deal...not enough to nix the sale if the price is right. Just my 0.032 CDN cents!!:)
 

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Base on his description, I'd suggest that it's as a result of carbon buildup in the motor, not wear.

What you've got is a motor that's been babied, not beat on, and never seen much high rpm use.

I'll bet you the valves are just fine and once you start to drive it regularly and give it some spirited driving, the carbon deposits will loosen up to a degree and you should see alot less smoke if any.
 

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I dont think so Logan. Look at it this way, 65k in 32 years and if the motor has never been apart I will bet at the least it needs valve seals. They have dried out , hardened and are probably laying on top the engine doing nothing. Those old guides used to wear bad back in those days also and the Cleavlands (I'm assuming its a Cleavland) canted valves and 1.7 rockers were even harder on guides than most others. It's funny though as some of the Fords in those days almost came from the factory needing a valve job while some lasted a long time, although none lasted as long as the newer vehicles do today. mm
 

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Logan......

Define spirited driving:1poke:


Don
 
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