Hello,
Bear in mind that I am not a car person at all… other than I love to drive and look at 'em. Well I recently bought a 1979 Ford Thunderbird, I then drove it over 350 miles home. I got home and the car sat for 2 days. I noticed while driving home with it that it had a “slight” tick in the engine. This occured about half way home. I stopped for quite some time let the engine cool off. I checked the oil, coolant, and other fluids and all was good. So I just drove it home with the noise. I mean you could barely hear it. Now a few days later it is quite a loud tapping or ticking. The noise does not occur while in park or neutral. It starts when you put the car in gear and start acceleration. The faster the acceleration, the faster the noise. As acceleration evens out and you start going a steady speed it goes back to almost nothing until acceleration again. Also it is a 351 Windsor engine. I know this could be a multitude of things. I was just hoping you could help narrow it down with the description.
Thanks,
Claude Smith
Sember, I had a Ford Granada with the same Windsor engine. This engine, built in Windsor, Ontario, Canada is really a pre-emission control design, unlike the Cleveland V8, which was a lot easier to fine tune. My Windsor engine had air injection (yours probably too)with a series of small pipes injecting air into the exhaust manifold to suppress emissions. The pipes quickly rusted or burned through, and I had a racing mechanic plug up all the intake ports and disconnect the air pump. This meant breaking the law, but the car had such poor driveability that I took the Catalytic converter off as well. This gave much more power and no stalling, which it did frequently. In short, this engine, used in pre-emission pickup trucks and large Fords, is a dog, and mechanics hate working on it. An old timer may be able to rectify your problem, which could be air leaking with the same frequncy as the power strokes. It makes a hissing and ticking sound. By the way, the new pipes on the dealers shelves had already started to rust right in the showroom, that is when I decided to cut my losses. If I had your car I would start looking for somthing more reliable.
Docknick is probably right about everything, but I’m guessing you knew that a '79 T-bird is not going to be the most reliable car in the world, and yet you’re still driving it. Let’s call junking it plan B.
The ticking, as you describe it, sounds like a timing issue to me. If I were you, my first step would be to get a full tune up, paying special attention to the ignition timing. It could also be a ticking from the valve train, either due to lack of adjustment of manual lifters or a failed hydraulic lifter. Other possiblities could be perfectly harmless piston slap or a bearing going bad, which would be bad. A good independent mechanic with some experiance with older cars should be able to tell you for sure.
My first thought was a valve train noise; probably a sticky lifter.
However, since the noise is not present in neutral or park you might consider a loose torque converter flex plate bolt. These can be checked by dropping the dust cover underneath and rotating the flywheel by hand (engine in neutral). Check the tightness of each bolt as it comes around.
You might also note if this noise is louder when the car is in reverse than in a forward gear. If so, then there is a very good chance the problem is a loose torque converter bolt. Just being a few turns loose causes the bolt head to hit the engine block.
The noise will not be present in neutral or park because there is no load applied to the flex plate. When a load is applied the flex plate will (imagine that) flex in one direction or the other depending on the trans being in a forward or reverse gear. Reverse tends to move the flex plate towards the engine block but eventually the bolts can be loose enough to make noise in any direction.
If the trans has been out of the car that that suggestion could be very relevant. If this is the problem, verify that the correct bolts have been used. These torque converter bolts have very shallow heads on them and if someone has used bolts with regular heads then they need to removed and pitched. Hope that helps anyway. 