76 R75/7 brand new heads and loud ticking?

[skittlz74]

Ok so I got a new rebuilt set of head with new valves, guides, springs, and milled seats, from reputable shop in Germany. (My old heads were pretty good, but developed a small crack so I went all in on these beauties.

Install went smooth, new gaskets and such. Valves set to spec as were the rockers. Needle bearings looked really good and I could not discern any play in the arms. Pushrods perfect. Also centered as per spec. Head gasket installed correctly.

Even installed new exhaust gaskets, nice and snug.

Left side purrs like a kitten, right side has very loud tick. Went for a 50 mile ride, pulled cover off and rechecked everything, all is still perfect. But this tick is really loud and makes me nervous.

Great compression, 150 on each cylinder.

Carbs are also perfectly synced.

Thoughts? PLEASE HELP!

https://youtube.com/shorts/iFO1JuTdgYc?feature=share

 

[stevenrankin]

Valves

Are the valve clearances adjusted properly? St.

 

[skittlz74]

Are the valve clearances adjusted properly? St.

Yes valves are set perfectly as per spec.

Checked the rockers a 3rd time, and oil is flowing as it should and there is zero up/down play.

 

[20774]

Well, you ticked off the things I was going to suggest. So, not sure. On a vintage forum where there was some noises from a /2 engine, the guru asked if the pushrods were straight. One could check them for straightness by rolling them across a flat surface to ensure there is no bend in the pushrods.

 

[pglaves]

If the exhaust gasket is reversed the openings for the push rods are aligned correctly and are egg shaped. This can allow the pushrods to contact the exhaust gasket and this can make a noise. So on the side that is ticking you should carefully make sure that the holes in the metal and the holes in the gasket line up and are round.

 

[skittlz74]

Well, you ticked off the things I was going to suggest. So, not sure. On a vintage forum where there was some noises from a /2 engine, the guru asked if the pushrods were straight. One could check them for straightness by rolling them across a flat surface to ensure there is no bend in the pushrods.

yes, the pushrods are perfect and zero markings from bumping the tubes anywhere.

If the exhaust gasket is reversed the openings for the push rods are aligned correctly and are egg shaped. This can allow the pushrods to contact the exhaust gasket and this can make a noise. So on the side that is ticking you should carefully make sure that the holes in the metal and the holes in the gasket line up and are round.

yeah the gaskets are correct; if you reverse them, they partially block the hole....so it's easy to make sure these are correct

 

[skittlz74]

also, i cannot really hear the noise with the cover off. i'll try to get a video of that tomorrow.

 

[69zeff65]

Check the exhaust header mounting

Check and make sure you installed the exhaust header all the way, the sealing rings are in proper order and it is nice and snug. It could very well be the source of the noise.

 

[kbasa]

I'll ask the stupid question, since it seems you know what you're talking about, but you rotated the motor between setting each side, right?

I know, I know. If you've done this before, scroll past, but when I was young and learning about boxers, I set both sides without rotating the crank for the other side and had exactly those symptoms.

And again, sorry if you did it right. I start every diagnosis on my own stuff by validating the assumptions I've made by testing them.

 

[skittlz74]

here is the video with the cover off....

https://youtu.be/9mvEq73ebJg

 

[skittlz74]

I'll ask the stupid question, since it seems you know what you're talking about, but you rotated the motor between setting each side, right?

I know, I know. If you've done this before, scroll past, but when I was young and learning about boxers, I set both sides without rotating the crank for the other side and had exactly those symptoms.

And again, sorry if you did it right. I start every diagnosis on my own stuff by validating the assumptions I've made by testing them.

yes sir

i'm going nuts trying to figure this one out!

i literally just took the head BACK off and re installed everything and set EVERYTHING to spec, and the same thing....

 

[kbasa]

yes sir

i'm going nuts trying to figure this one out!

i literally just took the head BACK off and re installed everything and set EVERYTHING to spec, and the same thing....

Yow. I figured, but it never hurts to ask. Thanks for taking it in the intended spirit. I'll show myself out.

 

[pglaves]

On one occasion, after going almost nuts, I tracked down a valve "tick" to a cracked camshaft follower/valve lifter.

 

[gtgt_bangbang]

got a mechanics stethoscope ? $6 at HF, I've isolated a couple hard to locate noises with those.
Just having the ear buds reducing the combined din of noises is a benefit.

Nice to have the accessible LR comparison possible with an airhead when sitting above it to know what a particular area 'should' sound like .


got any fans to cool during extended running?

 

[skittlz74]

On one occasion, after going almost nuts, I tracked down a valve "tick" to a cracked camshaft follower/valve lifter.

Is it possible to check lifters without removing the piston completely? Can the cylinder be slid back enough? That's one thing I haven't checked..

 

[Na Cl K9]

When the rod was exposed did you check for play in the big end and the wrist pin? How’s the oil pressure? It seems to only make noise in response to throttle. Your engine has very good compression, do you suppose it might be as simple as detonation?

 

[skittlz74]

When the rod was exposed did you check for play in the big end and the wrist pin? How’s the oil pressure? It seems to only make noise in response to throttle. Your engine has very good compression, do you suppose it might be as simple as detonation?

I haven't pulled the piston cylinder. Guess I'll do that tomorrow so I can check the lifters for pitting etc.

Oil pressure is fine. Not sure about detonation....

 

[gtgt_bangbang]

I dont want to be annoying and wont make a habit of repeating my self repeating myself,
but before I took it apart to the extent you mention

I would give it a very careful listen-over with a mechanic's stethoscope.
You have a "good side " for reference. Compare to the ticky side.
Compare many different spots side-to-side.
My gut feel is you may locate / zero in on the vicinity of the sound.

I've probed a lot of engines, bearings, accesories, all sorts of spinning & reciprocating equipment,
Plenty of time just for kicks but often enough for diagnosis.

Its sort of amazing;
probably as much from reducing the net / ambient / general noise pouring out of the 100 pieces all doing their thing in front of largish floppy ears,
but also by restricting your ears to tiny locations on the engine * the size of the probe) you can even locate various assemblies by their sound.
A clatter sound will likely get louder near the source, especially if its connected to a surface you can reach.
Sounds dampen as they move further from source.

I recall finding which bucket shim was loose spec & noisy just by probing up and down a valve cover.
I imagine probing each cam tower would have been good fun but I already knew where to look & didnt bother.

If it was the very much possible idea of a cracked lifter ( which, btw WASN'T there before the head work ? recall any thing funky during the install?) ,
I bet THAT related push rod tube, or better yet nearest rocker-shaft tower / clamp , ect would be noisier than the others.

IMO $6 well spent, before getting out the big tools.
Chicks dig em too. At least the squeaky loud ones I knew

That observation " cant hear the tick with the covers removed" may be a red herring but makes me think the sound is superficial.



I wouldnt go to a Dr that wanted to take my heart out before giving my chest a darn good listen either
but thats just me and thats all.

 

[gtgt_bangbang]

might be as simple as detonation?

salt dog has a good nose

If you already have the heads off, why not CC them?

If you dont have a burette, you can do that with some leveling / jigging on a cheap gram scale.
Which one gains more weight filled to the brim....
You can get by without a burette using a syringe & a scale too


A piece of drilled glass helps to prevent meniscus error

Do the squish bands look identical ?
Not much is a lot.

Germans make mistakes too.
May a bitte more clean up on the right side.

A tank of great gas ( the no-alcohol'er , the better) never hurt nobody nohow

 

[skittlz74]

Lifters look really good, as expected. Circlips and wrist pin look good. Everything inside cylinder head is nice and no scoring. I didn’t remove piston fully, especially since I have such good compression.

I am stumped!!!