Bum lifter??

[Don W.]

For quite awhile now my Sy has had a tick-tick-tick. just off idle Idle, part throttle, mostly is when you hear it. It -can- be controlled by throttle. However I'm quite sure it's not a piston or rod because it's been there way to long, somethin' would've went kablooy by now. Engine runs fine, pulls well, doesn't use ANY oil. Plugs look good. Truck goes to the track almost every week. I even did the stethoscope on the inj's and thought I had a loud one, Changed that one, didn't make any difference. I can recheck but I don't think that's it. (Trying to answer most of your Q's up front.)

Anyway, after a vacation and some other issues I fired the Sy today for the first time in three weeks. Exact same noise for a second or two until the oil hit the lifters. Normally I don't hear this because normally the truck runs way more often.

So... I'm fairly sure I have a bum lifter. But how do find it? I've already had the covers off and reset the preload on each one but there were no loose ones anyway. I know the feeler gauge trick but I hooping there might be another way. (Don't want to buy the clips make a mess, bla, bla.) Another reason for not using the feeler gauge trick is the noise is not there right at idle, I have to rev it a bit which will make finding the noise real tricky I would think.

Just thinking, maybe at idle there's no noise but I might still find a rocker "not as tight" as the others?

Thought? Ideas?

Thanks,

Don

 

[jwaller]

Re: Bum lifter??

check your oil pressure with a mech gauge.

I had this problem on a customers truck and after adjusting the lifters every couple weeks for a few months come to find out the dash gauge was useless. it actually had about 15psi at most with a real gauge and the lifters werent ever getting pumped up.

 

[WyoSyclone]

Re: Bum lifter??

I've got that same tick Don.... mine is loud and I'm so nervous about it being something serious.... I had my stethoscope out and thought I'd found a loud injector. Then I got the idea to stick the steth on the AFPR... HOLY COW!! it about blew my eardrums out! That's the source of my tick... my fuel pressure is on 48 and I guess it's just 3 injectors at a time banging back through the AFPR...

I am going to get a mech gauge and check my oil pressure though.... the gauges on these things sure make me nervous!

 

[Don W.]

Re: Bum lifter??

Hmmm, interesting thoughts. Oil pres ga is on the dash and line is run, just haven't made the connection at the filter so will take care of that. And check the AFPR while I'm at it.

Thanks!

 

[cloneman315]

Re: Bum lifter??

not saying this is your problem but this is how i set my rockers and every other set i have ever done and it works perfect,this way of doing it ,turn over the motor as soon as the exhaust starts to open set the intake wiggle it up and down untill there is no lash then a 1/4 turn,then the exhaust you want to open and close the repeat for the intake.Some guys say 1/2 some say 3/4 but i have never had 1/4 fail me and never had any noise.

 

[Don W.]

Re: Bum lifter??

not saying this is your problem but this is how i set my rockers and every other set i have ever done and it works perfect,this way of doing it ,turn over the motor as soon as the exhaust starts to open set the intake wiggle it up and down untill there is no lash then a 1/4 turn,then the exhaust you want to open and close the repeat for the intake.Some guys say 1/2 some say 3/4 but i have never had 1/4 fail me and never had any noise.

I've seen 1/4 turn mentioned before. Not sure if that's good or bad but one thing it does do is leave very little room for lifter "pump up" once the engine is warmed. :2cents: Prolly a good thing on a high winder. Our engines? Not sure. But thanks. Less is more probably applies here.

 

[cloneman315]

Re: Bum lifter??

man that build my engine built 4 other sytys and uses that spec also every other gm engine he builds,you should be fine with it ,

 

[cloneman315]

Re: Bum lifter??

how are you setting them?

 

[Don W.]

Re: Bum lifter??

Per manual, it was last winter when I did it, 1/2 turn if I remember.

 

[cloneman315]

Re: Bum lifter??

should work, but i would still try it like i mentioned,i have done it this way on many sy engines and worked well,lot of people think that this is simple and it is but a lot of people still will do it wrong,not saying that you are.

 

[Don W.]

Re: Bum lifter??

people think that this is simple and it is but a lot of people still will do it wrong,not saying that you are.

Yup, I would agree and, nope, no offence. Believe me I know what you mean. Sometimes people seem to have an innate ability to turn something simple into the biggest can o' worms you ever saw.

And BTW, regardless of adjusrment turns, I like to watch the opposing cyl as the valves "overlap" putting the cyl I'm working on at TDC. Then doing both valves at the same time. Any reason why that wouldn't work? Or are you using a different method to make sure the lifter is on the base circle of the cam?

Edit: Just had a thought. I would think that regardless of what adjustment I used last winter, since I did every rocker regardless, that the tick would at least change. It didn't. Which sends me back to other ideas -or- a bum lifter which no amount of adjustment will fix.

 

[cloneman315]

Re: Bum lifter??

its easier to do one cylinder at a time so you dont get messed up,it just makes it so the cam lobe is 180 off .and this way of doing will work with any engine.

 

[Don W.]

Re: Bum lifter??

its easier to do one cylinder at a time so you dont get messed up,it just makes it so the cam lobe is 180 off .and this way of doing will work with any engine.

True. See my edit above.

 

[cloneman315]

Re: Bum lifter??

maybe just one is not tight?but if it ends up being a lifter i def would just replace them all

 

[Don W.]

Re: Bum lifter??

Definitely!

 

[turboj91]

Re: Bum lifter??

Pull them one by one and inspect the bottom of each. See if one is concave. Check the appropriate cam lobe if needed.
I used to have a combo gauge set up. A dial indicator and pressure measurement indicator to see if any of the lifter springs were weak.
Also check valve spring pressures. I am sure you know why.

 

[92Typhoon1679]

Re: Bum lifter??

Ive got the same problem it sounds like loud lifters but my truck runs ok not great though im still trying to find out why ..my engine has only 50,000 miles on it but ive changed out my rockers to Pro Magnums 1.52 ratio but maybe ive adjusted them wrong i just rechecked the passanger side last week and they were sloppy so i readjusted them but i went by the book on adjusting them which says to do one turn past zero lash. i still have to do drivers side but that doesnt seem to help at all yet i will have to check my injectors next with a stethoscope. and im looking for a way to pressure check im intake for leaks i have a A2A intercooler so the bike tire method wont work.

 

[cloneman315]

Re: Bum lifter??

once again try the way i said not the way the book says it will work trust me,if done right these should not be coming untight

 

[Ry368]

Re: Bum lifter??

For quite awhile now my Sy has had a tick-tick-tick. just off idle Idle, part throttle, mostly is when you hear it. It -can- be controlled by throttle. However I'm quite sure it's not a piston or rod because it's been there way to long, somethin' would've went kablooy by now. Engine runs fine, pulls well, doesn't use ANY oil. Plugs look good. Truck goes to the track almost every week. I even did the stethoscope on the inj's and thought I had a loud one, Changed that one, didn't make any difference. I can recheck but I don't think that's it. (Trying to answer most of your Q's up front.)

Anyway, after a vacation and some other issues I fired the Sy today for the first time in three weeks. Exact same noise for a second or two until the oil hit the lifters. Normally I don't hear this because normally the truck runs way more often.

So... I'm fairly sure I have a bum lifter. But how do find it? I've already had the covers off and reset the preload on each one but there were no loose ones anyway. I know the feeler gauge trick but I hooping there might be another way. (Don't want to buy the clips make a mess, bla, bla.) Another reason for not using the feeler gauge trick is the noise is not there right at idle, I have to rev it a bit which will make finding the noise real tricky I would think.

Just thinking, maybe at idle there's no noise but I might still find a rocker "not as tight" as the others?

Thought? Ideas?

Thanks,

Don

Waaaay back in the day when I was running the stock heads I had the same issue with the press in rocker studs. I removed the covers as well and all checked out until I noticed one stud seemed to sit higher then the others.....the s.o.b. backed its way out after a couple quarter mile runs that I had experianced a little detination on!

 

[cloneman315]

Re: Bum lifter??

good point also