ticking noise from motor, what to do?

[00 scrub]

I just bought a 1992 Mazda Miata with 133k miles on it. It has valve train noise that is rather loud. It sounds like ticking that increases with RPM. I doubt it is bent valves as I ran a compression test and all the cylinders checked out fine. This car is known for ticking, but I don't have anything to compare it against (never really heard other Miatas). Is this lifter noise or sticking valves? Should I use Auto-RX or Schaffers 131 Neutra on this? If so which one? Also is Chevron's Techron useful?
thanks

 

[cryptokid]

what block you got?

the 1.8L? im really framiliar with mazda dhoc engines. so post your engine up and ill see if i can help you.

 

[00 scrub]

it's the 1.6 with a 5spd.

 

[cryptokid]

sorry mate, i dont know a thing on the 1.6

you might check your valves though. they may be out of adjustment if your engine has adjusters.
on the 1.8, if its out of adjustment ya replace the hydro lifters. but i dont know if your engine is this way or not.

 

[porterdog]

Hydraulic lifters, probably crudded up. When does it tick? Totally normal at startup (as long as 30 seconds sometimes) and/or after a hard run. Thinner oil will help at start, thicker oil will help for hot-tick. Also, it might not actually be lifter tick but carbon in the combustion chambers (really.) I'd try Auto-RX or a 5000mile run on Redline oil; if that doesn't help look into combustion chamber cleaning. **** , I'd probably do the CC chambers anyway, since a) Miatas run pig rich from the factory, b) it's cheap and easy.

More details on the Miata forum.

Robert

 

[00 scrub]

Well it seems the noise is there all the time. It is noticable during acceleration. I'll drive a little further and investigate it more.