Tapping noise in a 250...

[SteveMelchiorre]

My 69' Mustang w/ a 250 has started making a new tapping noise and I hope someone here can help me figure out what it might be.
Tapping is coming from the rear of the engine closest to the firewall and seems to be louder on the passenger side.
The noise is almost inaudible at idle but when the engine is rev'd it becomes quite pronounced.
The tapping increases in frequency as I rev the engine.
I had a cursory look around and could not spot any obvious exhaust leaks from the manifold.
I also recently changed the oil and filter. I put in Castrol GTX 10W/30 High Mileage.
http://www.castrol.com/castrol/productd ... Id=6030823

So.....valves, lifters, exhaust leak, or wrong oil?

Steve...

 

[Falconman62]

My first guess would be to double check for an exhaust leak. How I would do it is, with the engine running and cold, carefuly put your hand closest to the noise (try not to burn yourself) and see if you feel air being forced out. If you do than you have an exhaust leak.If you don't then I would say probably valves need adjustment. Just my two cents.

 

[SteveMelchiorre]

Thanks for the idea....and sure enough I was able to find exhaust coming out from the back of the exhaust manifold where it meets the block.
I'll have a better look at it over the weekend but if this winds up being a failed gasket would JB-Weld be an acceptable temporary solution until I can save up for a set of headers?

Steve...

 

[Falconman62]

I wouldn't use JB weld on something like that, I don't know what the heat tolerance is, but I just wouldn't use JB weld. Now if it just a failed exhaust manifold gasket, I am pretty sure you can get the stock gasket at Autozone, Napa, Checker, ect. for less than $20. Check it out and see what you find.

 

[SteveMelchiorre]

Fair enough.
On the JB Weld website they do not recommend it for Exhaust Manifold repairs....but there is a product from Permatex that is for this application. http://www.caswellplating.com/permatex/ ... prods.html

I'll use that for now and start saving my pennies....

Thanks again...

 

[Falconman62]

Permatex makes a squeeze tube gasket patch? Huh did not know that. Cool hope it does the trick. Keep us posted so we know if it is a good product or not.