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Thu Mar 03, 2011 11:13 pm

so I have a freshly rebuilt engine that is making a ticking noise. Posted the other day about it and since then have timed it, dialed in the carbs and re adjusted the valves. The ticking noise is still there. It can be heard at idle as a steady tick, tick tick. When I rev the engine the speed of the ticking noise increases until it is undistinguishable from the engine reving. The original post turned into a debate about oil selection so thought I would start new. need to know if anyone could point me in the right direction concerning the noise. what has been experience with this type of noise, what to check, what can be done without disassembeling the engine ect. would really like to avoid tearing the whole engine down if I don't have to. Really need some help with this, thanks!

Fri Mar 04, 2011 12:23 am

The reason your other thread went that way was because we are concerned about the welfare of your engine, have a read through some of the threads on here over the last couple of years about cams going flat, lifters pitting etc, it could very well be the source of your noise.

Anyway back to the issue, does your engine tick when you turn it over by hand? Have you isolated the noise or tried to? you can remove the belt and run the engine safely for a moment to figure if its a fan noise or block related. Block related take off the valve covers and turn it over by hand while watching the valve train, do any of the valves stick and pop shut, recheck your tappet clearances. What was your end float spec?

Fri Mar 04, 2011 5:34 am

Sorry I was not dismissing or complaining about the input concerning oil selection. I should have started this post by saying I plan to change the oil to one of the recomended ones and add the zddp as my next step. However the sound started from the first start up of the engine, didn't develop over time so I am trying to figure it out.
Can't hear the tick when I turn it over by hand. The noise sounds like it is coming from the 1/2 side either in the head or the case. I have taken the fan belt off and the noise still persists so it is not fan or shroud related. I have had the covers off and had someone turn the engine over by hand-all valves are working properly and in a fluid motion (even put my dial micrometer on a couple to measure that the lift is still what it should be and it is.)
Not sure what you mean by end float spec- if you explain it for me I will check that as well and report back.
Again I am greatful for any and all help, please don't think I ment anything negative about the previous post- assumed I was being unclear and wanted to try the question again :oops:

Fri Mar 04, 2011 1:34 pm

So here is what it sounds like any thoughts?

Fri Mar 04, 2011 1:39 pm

:shock: that doesnt sound good.
it sounds intermittent, like a valve occasionally sticking and causing the rocker arms to tap?

Fri Mar 04, 2011 2:51 pm

norcalmike wrote: :shock: that doesnt sound good.
it sounds intermittent, like a valve occasionally sticking and causing the rocker arms to tap?

X2 really sounds like a valve or lifter getting hung up. i would run it with the valve covers off and see if you can watch the rockers and valves. you may be able to see something hang up.

is it ok when its cold? maybe a valve guide is getting tight when it warms up

Fri Mar 04, 2011 5:37 pm

I know that the valve adjusters on the #2 & #4 exhaust seem to need constant adjustmnet. Each time I have run the engine and then checked the valve clearance they will be off by about .015 on each side. The rest of the valves only need minor adjustment to get back to a loose 0 by comparison. Would this be a sign the valve is sticking on one side of the engine (one lobe controls both valves.)
I am going to take the rockers off next chance I get to check the pushrods to eliminate that as a possible cause (doesn't seem likely but doesn't hurt to check.)
If the problem is a sticking valve what is the solution, I know the head will have to come off and the springs, keepers ect will have to come off, but will it need a new guide if the valve is fine or if the valve is bent will it need a new valve and guide? Is this something I should take to a machinist to fix or can it be done at home?

Fri Mar 04, 2011 5:53 pm

You might check the torque on the head studs. 8mm? new studs?

Fri Mar 04, 2011 5:57 pm

Yes 8mm. Studs, case, nuts all new. Will be checking torque on head nuts again when remove the rocker assembly.

Fri Mar 04, 2011 6:01 pm

yep. you gotta retorque them. Check compression afterwards to make sure you didn't burn a head.

Fri Mar 04, 2011 6:32 pm

mkystybx wrote: yep. you gotta retorque them. Check compression afterwards to make sure you didn't burn a head.

Burn a head? Not sure what that's about. Did you check that your pushrods seated properly into the end of your rocker arms?

Fri Mar 04, 2011 6:36 pm

Yes, the pushrods were seated properly in the rockers and lifters-had an issue with that previously so alwasy double check it.

Fri Mar 04, 2011 6:50 pm

I could guess all day, but that sound does remind me of the time my nephew who is 3 tossed a small nut down the intake and it stuck to the top of the piston! Are the rockers hitting the back of the valve covers?

Fri Mar 04, 2011 10:02 pm

I don't mean to make a stupid guess but, could you have an exhaust leak close to the head (i.e. the gasket didn't seal.)

Fri Mar 04, 2011 10:26 pm

vdubnut58 wrote: Are the rockers hitting the back of the valve covers?

X2 common problem with those covers, have to clearance where the adjusters are.
Past that those covers are the best!

Another concern is that you say your constantly adjusting the #2 and #4 exhaust valves, those valves share a common cam lobe, that's not a good sign! You could have a bad lifter or lobe, pay close attention to the lift of those valves and compare that to another valve.

Fri Mar 04, 2011 10:36 pm

SRP1 wrote: vdubnut58 wrote: Are the rockers hitting the back of the valve covers?

X2 common problem with those covers, have to clearance where the adjusters are.
Past that those covers are the best!

Another concern is that you say your constantly adjusting the #2 and #4 exhaust valves, those valves share a common cam lobe, that's not a good sign! You could have a bad lifter or lobe, pay close attention to the lift of those valves and compare that to another valve.

I don't have experience with those covers but I had this issue with stock covers and it caused it to pop out the carb on a couple of valves, well worth having a look at the ends of the rockers and in the covers for marks.

Sat Mar 05, 2011 6:30 am

That is the sound of a pushrod ball end coming out of the lifter socket.

Make sure when you adjust the valve lash to cycle the engine by hand 1 full rotation to make sure the ball is seated in the lifter.

The ball end could get hung up and not seat in the lifter and it might feel it is on there but not really. When you hear this sound, then you know it is not in.

What cam did you finally end up putting in this motor?

If you find it loose after adjustment, then take up that slack, turn by hand 1 full turn and check the lash..if it still loose-zero.

If it is done right, should hear slight, tiny tappings but not "clattering sounds".

Don't run it long like that or the lobes and lifters will eat each other. If you hear it, stop the engine and adjust it.

Sat Mar 05, 2011 7:44 am

vdubnut58 wrote: mkystybx wrote: yep. you gotta retorque them. Check compression afterwards to make sure you didn't burn a head.

Burn a head? Not sure what that's about. Did you check that your pushrods seated properly into the end of your rocker arms?

Yes, if it is leaking between the cylinder and head for any length of time it will melt the aluminum at the sealing point. I saw a head at pomona last year with a whole that you could stick a quarter through.

Let us know what you find.

Sat Mar 05, 2011 8:32 am

Being that you have to constantly adjust valves 2 and 4 says to me it is lobe going flat. Check valve lift with a dial indicator.
Check also side play on your rockers. That can also give you the ticking sound.
Could a push rod tip be getting pounded into the end of the rod? Check and measure all of them to find out.
Lifter bores wore out?
But it really sounds like a flat cam to me.

This happened to me after only about 3k miles.
Probably started right during break in from using the wrong oil.

Sun Mar 06, 2011 8:36 pm

Update:
So here is what I have found
No problem with valve covers, plenty of room
All pushrods are good, not bent, same length I had them cut to and the ball ends are all good
Checked torque on all head nuts, all good same for nuts on rockers
Set the rocker side play when built engine and it is still same all between .003-.005
But here is where I think the problem is
Using an enge 110 cam and measured the lift with dial mic and here is what I found. All intake valves between 380 and 390. Exhaust on 1& 3 also between 380 and 390. However, exhaust on 2 & 4 both about 340 big difference. So it seems I have a bad lobe.
It seems there is nothing for it at this point except to tear the engine apart again and get a new cam.

If this assessment seems wrong please let me know, it will be about a week before I can get to tear the engine down again.

Since it seems I will have to replace my cam any suggestions as to what would be the best to use (engine 1915, not race will live its life mostly below 6000rpm) If I have to replace it might as well get what will maximize my combo

engine specifics: using 1.1 solid shaft rockers, 36 dells, header exhaust with dual quiet pack, cb heads 40-35 valves match ported to intakes, msd ignition, svda distributor with pertronix, counterweighted crank- everything balanced in rotating assembly, compression ratio about 8.4