Clicking from motor?

[jasontiff]

The other day I was driving and noticed a RPM-dependent clicking from the motor. It got faster as I accelerated and wound down on decel. I pulled over and heard it predominantly coming from the drive side around the rockers. I took it easy on the way home and opened the valve covers and can't see anything. I thought maybe we didn't put enough clearance in the oil baffles when we put the 1.7s on there but it still made the noise with the covers off. I tested the pushrods and none of them were loose, and none of the rockers had visible signs of wear. Could one of the new lifters be bad?

I'd like some ideas on diagnosing before digging any deeper than I have. Any thoughts? Thanks, guys!

 

[99 R/T 10]

I know th einjectors make some noise while the car is running. Does it seem to be coming from the rockers or could it be th einjectores that you hear? Also, if you have the covers off, check to make sure all the rockers move the same. If one is not moving or only moving slightly, that could be the cause.

Mike

 

[ViperTony]

With the covers off while the engine is running, isn't oil getting everywhere?

 

[Martin]

Also look lengthwise along the pushrods to see if they're bowed out. I've been battling a bizarre rash of bent pushrods. Same symptoms as yours - a clicking sound like from a bad lifter. When I pulled the valve cover over the weekend, I saw that a third pushrod gone bad for no obvious reason. Strangely, all three of mine went bad on the driver's side, too...

Are you still using the stock pushrods?

 

[jasontiff]

Also look lengthwise along the pushrods to see if they're bowed out. I've been battling a bizarre rash of bent pushrods. Same symptoms as yours - a clicking sound like from a bad lifter. When I pulled the valve cover over the weekend, I saw that a third pushrod gone bad for no obvious reason. Strangely, all three of mine went bad on the driver's side, too...

Are you still using the stock pushrods?

I upgraded to some magnum Comp Cam something or other hardened pushrods; not chromemoly, but not stock.

I'll take a look at that. It's weird; I have 700-800 miles on the motor since the heads/cam/valvetrain/etc., and the dyno tune was 300 or so miles ago and it just now started doing it.

 

[jasontiff]

With the covers off while the engine is running, isn't oil getting everywhere?

Yeah

I really need someone to come over and listen quickly so I don't have to do the driver-to-motor shuffle and back when I'm listening. I have some towels over the headers and the car was cool when I started it so nothing is gonna go up in flames...it's just gonna make a mess.

 

[jasontiff]

I know th einjectors make some noise while the car is running. Does it seem to be coming from the rockers or could it be th einjectores that you hear? Also, if you have the covers off, check to make sure all the rockers move the same. If one is not moving or only moving slightly, that could be the cause.

Mike

When we did the heads/cam, we also swapped my Gen. I 4-rib intake for a Gen. II 3-rib with the stock Gen. II injectors. There was a little noise from the valve train initially but we modified the oil baffles and the tapping went away. If it's the injectors, is there is a reason they'd start making the noise almost 1000 miles after we modded the car?

If I bent a pushrod or had a bad lifter, would there be slack in one of the RR? I'll be sure and start it again and look to see if one is moving significantly different than the rest. I just don't want to start pulling RRs off and pushrods out before having a clearer idea of what/where it is. I isolated which side of the motor it's on and have it narrowed down to 5, 7 or 9 but that's still a lot of work without really knowing the cause.

Thanks, guys!

 

[triblk6spd]

Dude! I told you if you need some help to give me a call. In my past life I lived next to a mechanic.

 

[jasontiff]

Well, a friend with a Z06 (who happens to be a mechanic) came over unexpectedly and helped me look at the car. We found a bent pushrod and the locknut being completely loose on the intake side of #6.

Question: How straight should a pushrod be? We took it out and rolled it slowly over the kitchen counter and there was a subtle yet very present bow in the middle of the rod. Do pushrods normally have a tiny bit of variation or should they be completely straight?

Secondly, should I just order a new pushrod from Comp Cams or order a new set of chromemoly ones somewhere else? Recommendations?

 

[triblk6spd]

They will be PERFECTLY straight. Do you have a theory on why it bent in the 1st place? Did you save your old ones, and are they the same length?

 

[plumcrazy]

pushrods are dead straight. a friend had the same problem with 2 of his pushrods. replaced them and never had a problem. easy fix

 

[ViperTony]

Well, a friend with a Z06 (who happens to be a mechanic) came over unexpectedly and helped me look at the car. We found a bent pushrod and the locknut being completely loose on the intake side of #6.

Question: How straight should a pushrod be? We took it out and rolled it slowly over the kitchen counter and there was a subtle yet very present bow in the middle of the rod. Do pushrods normally have a tiny bit of variation or should they be completely straight?

Secondly, should I just order a new pushrod from Comp Cams or order a new set of chromoly ones somewhere else? Recommendations?

They should be perfectly straight. When I did my T&D's last year, I installed a set of Trend double tapered pushrods from Dan at Viper Specialty. Definitely worth the money IMO. What cause the pushrod to bend? Loose locking nut?

 

[Martin]

pushrods are dead straight. a friend had the same problem with 2 of his pushrods. replaced them and never had a problem. easy fix

This pushrod thing is really bizarre. I was on the SRT chat last night asking them about what the deal is with my bent pushrods and they seemed to think there must be a problem. I've also had a couple of friends who lost pushrods on their Gen 1 and 2 cars, and just like me, they replaced them and everything was fine since.

I wonder if a bad batch of pushrods made it into the system way back then. When I originally bought my '97 GTS I was hearing that telltale tapping sound, and the dealer told me it was probably just the injectors. I drove it for ten years with no problem, and then all of a sudden I lost two pushrods. After replacing them, everything was fine - and the tapping sound that I heard when the car was new was GONE. Kind of leads me to think that I had a few bad pushrods to begin with, and they just finally gave up the ghost.

 

[jasontiff]

They will be PERFECTLY straight. Do you have a theory on why it bent in the 1st place? Did you save your old ones, and are they the same length?

Yeah, this one is not perfectly straight.

As far as the cause, it's a "chicken before the egg" thing; did the pushrod bending cause the locknut to loosen, or did the locknut loosening cause the bend? Also of note: I bought all this stuff from Scharf off of a salvage car. The rods were wrapped in cellophane with no additional padding and thrown in with the rest of the stuff (180 lb heads), so it's possible it was damaged before it came off the other car or got damaged in transit and I didn't see it.

I didn't save the old ones. These are the rods that came with the heads I bought from Scharf, so they may be a different length depending on much the heads were massaged/decked, if at all. If the number on the rod corresponds to a length, they're Competition Cams Magnum 7693.

Hopefully ordering some nice pushrods and swapping them fixes the problem. It sounds like it will. Looks like the car will be down for another weekend though; no TX2K9 for me DAMMIT.

 

[ViperTony]

Yeah, this one is not perfectly straight.

As far as the cause, it's a "chicken before the egg" thing; did the pushrod bending cause the locknut to loosen, or did the locknut loosening cause the bend? Also of note: I bought all this stuff from Scharf off of a salvage car. The rods were wrapped in cellophane with no additional padding and thrown in with the rest of the stuff (180 lb heads), so it's possible it was damaged before it came off the other car or got damaged in transit and I didn't see it.

I didn't save the old ones. These are the rods that came with the heads I bought from Scharf, so they may be a different length depending on much the heads were massaged/decked, if at all. If the number on the rod corresponds to a length, they're Competition Cams Magnum 7693.

Hopefully ordering some nice pushrods and swapping them fixes the problem. It sounds like it will. Looks like the car will be down for another weekend though; no TX2K9 for me DAMMIT.

After the cam work, did you check for pushrod length using a pushrod checker? I'd do that now while you're in there just to verify you do have the correct length pushrods...it may avoid more problems down the road.

 

[jasontiff]

After the cam work, did you check for pushrod length using a pushrod checker? I'd do that now while you're in there just to verify you do have the correct length pushrods...it may avoid more problems down the road.

Good point...I might as well do it right now and avoid potential future problems. As fun as it is pulling the valve covers off every other week, I'd rather avoid the hassle

I think we assumed that the pushrods would be the correct length given that they came with the heads, but I did switch the cam and lifters that were originally with those pushrods.

Since I'm impatient and don't want to order one and wait 5 days, any Austin guys have a measuring tool laying around? I know a friend in Wimberly has one but I won't be down that way today.

 

[bluesrt]

if you are not giving them enough clearance(over tightening them)if u run it in high rpm,at any given time u can bend a pushrod,the old sayin leave them loose to produce,but not to loose,u have to have some common sense..

 

[ViperTony]

Good point...I might as well do it right now and avoid potential future problems. As fun as it is pulling the valve covers off every other week, I'd rather avoid the hassle

I think we assumed that the pushrods would be the correct length given that they came with the heads, but I did switch the cam and lifters that were originally with those pushrods.

Since I'm impatient and don't want to order one and wait 5 days, any Austin guys have a measuring tool laying around? I know a friend in Wimberly has one but I won't be down that way today.

When I installed my rockers, measured the pushrods and adjusted them I followed JackB's chart below...it works if you follow his advice here: http://forums.viperclub.org/illustrated-upgrades/602295-adjusting-roller-rockers-made-easy.html

 

[jasontiff]

When I installed my rockers, measured the pushrods and adjusted them I followed JackB's chart below...it works if you follow his advice here: http://forums.viperclub.org/illustrated-upgrades/602295-adjusting-roller-rockers-made-easy.html

That's damn helpful...looks like I'll need a fancy TDC doohickey and a badass socket for turning the crank. Thanks!

 

[plumcrazy]

No need for measuring or TDC positioning if its oem valvetrain. Buy an oem pushrod. Used even....
When it happened on my buddies viper I talked to tator and he said it does happen spmetimes foe no reason. Something about high rpms and there being a split second in time where the lifter and pushrod float I think. He said to replace amd forget about it. A year later and its fine still. As usual chuck was right.

 

[jasontiff]

No need for measuring or TDC positioning if its oem valvetrain. Buy an oem pushrod. Used even....
When it happened on my buddies viper I talked to tator and he said it does happen spmetimes foe no reason. Something about high rpms and there being a split second in time where the lifter and pushrod float I think. He said to replace amd forget about it. A year later and its fine still. As usual chuck was right.

I've got 1.7s on there, but I believe the retainers, locks and springs are stock.

So I looked up the pushrods that came with the heads/cam, and they're overall length is 7.900 according to Summit. On Dan's site, the common sizes were 7.500, 7.600 and 7.700. Do aftermarket RRs usually call for a longer rod? These do have a lockplate of some sort (they're Isky) beneath, but it's not .200"-.400" worth of plate. I'm debating on just getting another from Summit for $6 and seeing if it happens again (it was fine for 1000 miles) or measuring and seeing what the real deal is.

 

[ViperTony]

No need for measuring or TDC positioning if its oem valvetrain. Buy an oem pushrod. Used even....
When it happened on my buddies viper I talked to tator and he said it does happen spmetimes foe no reason. Something about high rpms and there being a split second in time where the lifter and pushrod float I think. He said to replace amd forget about it. A year later and its fine still. As usual chuck was right.

Not OEM valve train...rockers, cam and lifters are aftermarket. I can't imagine not measuring...it's not that much more work.

Jason: You can make a TDC gauge out of a straw...Also, Dan lists the common sizes but you can custom order any length you need. It may turn out you have the correct sized rods and just need to replace one rod. At least you'll know and have peace of mind. I don't think Scharf actually checks out these details but I could be wrong.

 

[jasontiff]

I saw that you could order the custom sizes but thought it was odd that mine were dramatically above what "normal" was deemed on the site.

I think I'll order another $5 pushrod or 2 from Summit so I can be back up and running and have a backup, and if I get the same thing I know what it is and will be able to tackle it.

Thanks, guys! I guess you gotta pay to play...oh, and I never posted my numbers. I wound up with 460/500 with the stuff I did and a conservative tune. It's louder and quicker on the bottom end, so I'm happy...I just need to quit breaking stuff so I can get out and enjoy the weather!

 

[plumcrazy]

just wanted to make sure anyone who reads this a year from now with all OEM parts doesn't panic so much. thats all.

 

[vp97]

What kind of rockers are you using? 7.900 length pushrod is way to long. You might want to recheck that!

 

[jasontiff]

The rockers are Isky 1.7s.