Rod/rocker recommendation? (Page 1/1)
tbone42 NOV 04, 09:29 AM
86 Fiero 2.5 Isuzu 5 speed 73k miles


Howdy folks! I'm getting some suspected rod noise In my #1 and compression is slightly lower but it sounds like it's at the top of the engine. I'm thinking maybe it's wore or slightly bent so I'm gonna replace my push rods and rockers hopefully before anything goes wrong with the originals.. I have in the past seen people mention different rockers as an upgrade , so my question is: should I go standard or is there something different/better I should be upgrading to?

Would like to order this stuff this weekend so I can do it next weekend. Anyone have any recommendations? Appreciate it.

-T

[This message has been edited by tbone42 (edited 11-04-2023).]

82-T/A [At Work] NOV 04, 09:50 AM

quote
Originally posted by tbone42:

86 Fiero 2.5 Isuzu 5 speed 73k miles


Howdy folks! I'm getting some suspected rod noise In my #1 and compression is slightly lower but it sounds like it's at the top of the engine. I'm thinking maybe it's wore or slightly bent so I'm gonna replace my push rods and rockers hopefully before anything goes wrong with the originals.. I have in the past seen people mention different rockers as an upgrade , so my question is: should I go standard or is there something different/better I should be upgrading to?

Would like to order this stuff this weekend so I can do it next weekend. Anyone have any recommendations? Appreciate it.

-T





Hey T, does it sound like a deep rod knock, or actually just lifter clatter?

Big differentiator is if you see a drop in oil pressure... that would usually mean a main bearing that's going out. But if you're just getting lower compression and down on power, it could very well be a bent pushrod or a collapsing lifter. I unfortunately can't answer the question about the rocker arms... but I am definitely interested to know if there are any "bolt on" rocker arms that we can install that will improve performance / reliability too... doing the same thing to my daughter's Fiero.
tbone42 NOV 05, 09:23 PM

quote
Originally posted by 82-T/A [At Work]:
Hey T, does it sound like a deep rod knock, or actually just lifter clatter?

Big differentiator is if you see a drop in oil pressure... that would usually mean a main bearing that's going out. But if you're just getting lower compression and down on power, it could very well be a bent pushrod or a collapsing lifter. I unfortunately can't answer the question about the rocker arms... but I am definitely interested to know if there are any "bolt on" rocker arms that we can install that will improve performance / reliability too... doing the same thing to my daughter's Fiero.



My oil pressure does float a bit between 40-60 but I am also almost sure I need to install an oil pressure sender. It's leaking a little and I have that new part already for my oil change I'm doing Tuesday.

It is down on power because the noise kicks in when I am under load and stepping on it. I can adjust the gas pedal and pull back and the noise stops. I barely hear anything in idle using the big screwdriver to my ear method. I was also suspecting a noisy TBI but don't think that's it.

#1 is about 15 psi less than the other cylinders which are spec. Noise is coming from the battery side, I can even tell with windows up it's behind the passenger.

I believe it's a bent or wore rod. They're original and I had a high idle rev that didn't sound good a few weeks before it started up.
Been driving it too long in my opinion, tempting fate.

So, I've never replaced rods and rockers before and I actually want to do this even if it's valve noise. Just trying to figure out if there is any advantage to doing anything besides stock replacement on the rockers, like roller rockers...but nothing I need to dig further into the engine to get at. Probably just go stock, found a set for a hondo.

Thanks for the reply Todd