JPL

Problem: I'm experiening a ticking noise that sounds like a exhaust leak when the engine is under load around 2-3.5K RPM. It's a ticking noise coming from the front/engine area, almost like a valve noise. Not bad just subtle and annoying.

History: I have a new/ rebuilt engine with about 6K miles. I recently had LCEngineering headers installed with a full custom exhaust system and muffler. I noticed the noise after the install of the exhaust (not directly after but within a day or two). I brought it back to the shop and they couldn't find a problem but they can hear the noise and recommended me to drive it more so they can "see" where the exhaust leak is coming from. I drove it on a trip to Phoenix over the weekend and inspected the system when I got home.. I noticed a stud fell out from the cylinder head that secures the header. I had the shop replace the stud and torque everything down.

Now that everything is torqued down and in place it's still making that noise (no change). I thought it could possibly be a burned exhaust valve so I checked compression today. #1= 135, #2= 140, #3= 130, #4= 130. I now know it's not a bad valve. This is driving me crazy even though it doesn't seem to be affecting performance.

Theories: Bad gasket on header, leak from collector, ???

Also, I had the valves adjusted a while ago so I had the shop re-check the valve adjustment and they're saying everything looks good (I can tell the valve cover was removed so I'm pretty sure it was re-checked).

As you can likely tell I'm pretty picky when it comes to my rig so this is really stressing me out. Thanks for any help on this.

xxxtreme22r

low rpm, large throttle (load) you sure it's not an engine ping in one cyl that the knock sensor isn't picking up?

What does your plugs look like?

JPL

All plugs were the same: light beige and dry (lean). It's more of a lower noise not really a metal tap. I'll see if I can record the noise when I have time.

xxxtreme22r

Weren't you running rich at one point? And 130 psi sounds a little low on the compression I know your running a higher compression but a bored engine, but Spec on the compression should be between 142 and 170ish. Your way below that. With 6,000 miles on that thing, your rings should have seated by now. Or should be at least close. But your still out of spec.

I'm bored 30 over, block shaved 10 thous with standard compression pistons and I was around 170psi with 500 miles on my engine. I haven't checked my compression since. I have 15K+ on mine now.

JPL

Maybe I should have a shop that specializes in 22re engines look at it, I really hope it's not the engine. It has been quite reliable so far and never seemed to have higher compression than stock. I've got a feeling this rebuild is completely stock... It's strange that all cylinders are consistantly low. I would expect a couple high and maybe one or two low.

Black_1985_SR5

iTrader: (1)

That's those Kb pistons for you bad compression was foretold

xxxtreme22r

Or the rings have not seated like I had stated about those crappy KB pistons. I'm curious how you went from going rich to nor somewhat normal plugs.

When you bore out an engine you loose compression. And you only went from 9.4:1 to 9.7:1. If your 60 over, I might see why you would be low, but if your only 20-30 over on the bore you should be close to 170. Not 130.

I'd say you don't know how to use a compression gauge, but your numbers are close enough together to rule that out. Other then the 10 psi difference from 130 to 140 on one cyl. And that rules out a miscalibrated compression gauge IMO.

JPL

I don't think I have "bad" compression. There has been no performance change and all cylinders are within 6%. I'm not experiencing lack of power just an "exhaust leak noise".

Black_1985_SR5

iTrader: (1)

I think that's low enough to consider bad

xxxtreme22r

engine spec on a 22re is 142-170 you have 130-140, you have bad compression. If that was an engine with 180,000 miles on it, I'd say the 130 was "good" But you have 6,000 miles on that engine. When I had 500 on mine I had 170psi, and two of my cyls were at 172-175.

I'd say valves not sealing properly accross the board due to wear was a factor, but you have a brand new head like I do.

Toss some oil in those cyl and do a compression test again, I'd be willing to bet you get a higher number.

JPL

I would speculate the lean running would be because I'm at 7K + feet and I never had a rich running issue with the new rebuild.

I've done compression test before. I removed all plugs and turned over the engine a few times on each cylinder.

xxxtreme22r

OK your right, I speculated that and someone else in that thread was running rich as well as many other running these pistons.

You ran your old engine at 7000 feet right? With a complete rebuild at the same sea level you should see a significant power increase with even a stock rebuild, considering one of your cyls was only putting out 80 psi.

But you have not gained ANY compression buy rebuilding a 260Kish engine.
Why? Because your engine compression has not improved. Why? Rings didn't seal.

That explains why you haven';t seen a performance increase in this engine when compared to the old engine.
No compression increase = no power increase.

JPL

My old engine was run at 7K feet elevation and compression test was 80 to 120 psi. At sea level I'm seeing much more performance increase. It runs just as good as it did when it was new 0 miles on the new rebuild. It might be a crappy piston but I'm not seeing any change.

Are you suggesting that I need better rings?

Also, I did see a performance difference from the old engine. Not much but it does have a little more power.

xxxtreme22r

BTW in no way do I think the low compression has anything to do with the noise your hearing unless it's a slight engine ping. Which would be possible if fuel is pushing past poorly seated rings. This is one reason why a KB piston engine runs rich in a fuel injected truck. ECU thinks your lean and keeps sending fuel, which will richen the cyl where the blowby is the least.

I hope that makes sense.

xxxtreme22r

Your now effectively at 130 130 140 135. Not much different then that 263K engine. IMO a freshly rebuilt engine should be getting at the very least 150-155psi.

JPL

I can see your point but the readings on my old engine were done at the shop and the recent readings were done by myself. I doubt it would make much of a difference using a different guage/ tool. I plan on checking my compression again tomorrow or on the weekend. I only cranked over the engine for 3 seconds twice per cylinder.

I did expect more performance from this engine and that's why I think it's stock.. The thing that gets me is that it runs exactly the same as it did when it was new.

I feel this thread is getting off track and I'd like to find that noise. At this point I almost don't care about this stupid noise, I feel like starting all over with a different engine. You guys are starting to convince me my engine is crap. This is a little depressing after all the money invested. Although, I get the feeling everyone on this forum is bias to KB pistons.

xxxtreme22r

I am sure someone on here might be for the KB pistons, but everyone I have seen on this forum has had issues with an engine that had them in it.

Twice per cylinder is about right. And the shop versus you isn't much of a difference.

Running the same as it did new is somewhat normal, but running the same as the old tired 263K mile engine is not normal. Which it sounds as if it is. The fact the compression reading are similar to that of your old engine supports why it's not running any better.

Even with stock parts, 130ish is way too low. As I have 170-175 in mine. And even now I think I have more blowby then I should. Meaning I have almost convinced myself my rings haven't completely sealed and I should be in upwards of 180ish on my compression reading. Unless I am currently getting less then I did with 500 mile on it when I compression checked for health.

JPL

How would you correct this (my) problem? Replace the piston rings and pistons?? I'm sure my compression should be much higher like you stated.

xxxtreme22r

Now one thing that I am not accounting for, is the cam. I know some cams going back to my SBC/Drag racing days, that some cams affect engine compression and vacuum. I don't know for sure if the 272 cam is one of them.

As far as fixing the compression, I suppose you can replace the rings and try again.
Not sure if I would reuse the rod bearings or not though.

Not sure if the KB pistons must use their specific brand rings or not.

I would also hone the cyl walls again as well. Not bore, just hone.

JPL

I don't exactly understand how the cam could affect compression. I thought it was the pistons that make all the difference on compression level.