Bonneville America Forums Forums Technical Forums General Tech hammering sound after valve adjust

After ordering micrometer, bucket retaining tool (useless), shims, and dealing with ridiculous work schedule, finally got my bike back together after 12,000 mile valve adjustment. Fired right up, but after about 20 seconds or so, this banging noise gradually starts. I panic, of course, shut it off. Re-checked clearances, rotated wheel in 5th gear, everything looks good. Spun wheel around as fast as I could by hand maybe 10 or 12 revolutions, oil pumping fine, no sticking valves, all shims seated, now oil is all over engine. I know I didn't drop anything down in engine, no missing parts, no cam caps backwards, I did everything with surgical precision. Put it back together and tried it again. Same thing. No noise, then this sickening banging sound gradually starts. Then it just goes away. Just rode about 40 miles all speeds, everything fine. Anyone have any thoughts on this? I had 4 loose valves, now sewing machine noise is much diminished.

So the noise is gone completely? Even when it's cold?

Can you borrow a mechanic's endoscope? Remove your plugs and check the tops of your pistons.

I'll fire it up when I get home. Last night, it probably cooled off between the time I tested it and when I cleaned up everything before I rode it. Maybe 1 1/2 to 2 hours. When I tested it, only ran it for about 2 or 3 minutes. Check top of pistons for what? Looked in there before I installed new plugs, yep, piston tops were in there. Only thing I can think of is maybe some contaminant was causing a shim bucket to stick, I dunno.

I think Phil is getting at looking to see if there's any damage from valves hitting pistons, if you possibly set your cams incorrectly and altered your valve timing.

Wonder if it could be something from the valve adjust settling in. Something that wasn't seated perfectly then once it did the noise went away. Can't imagine what, but some times there are things you'd never have considered. If it's gone now as you seem to be saying i'm sure you're fine.

Sounds like you may have an oil pump close to failing? Kinda hard without actually hearing it myself.
I would triple check the clearences again to be sure. As well as the cam timing marks. They need the little dots and dashes to be inline with the oposite side saying "TOP" at the top. Left cylinder should be at Top Dead Center then. Sometimes you have to rotate the motor several times to get it right as the cylinder goes two full turns before it is at the correct timing position.
Also, check that you have the intake/exhaust cams in the right positions.
Not saying they are off, just double and triple check everything!

You did use metric feeler gauges?

Larry

Thanks for all the replies. Checked clearances a couple of times, everything within specs. Cams in proper locations, grooved intake in back, timing marks with dots and dashes just like pictures- didn't turn engine with cams out, oil pump pumping like crazy thru all 4 caps- made a mess. Oiled everything liberally during re-assembly to the point I was almost overful (top mark in sightglass). Metric feeler guages with inch micrometer- used Dinqua's converter to calculate new shim size and they all fell within specs first try. Had both left intakes loose and both right exhausts loose. After noise quit, the thing ran great. A little quieter than before valves adjusted. Ran around town last night, idled at a couple of long red lights, up to 95 (indicated) on I-10, no problems. It hasn't been started for about a month, didn't want to ride until I checked clearances and have been working 7 days a week. Maybe something was too dry and it just took a while for oil to get to it. Is it possible to have too much oil under bucket causing a hydrolock? Now I'm thinking too much. I'll have to leave work early and start her up.

As long as it is quiet now I wouldn't sweat it anymore. The valve shims need to "click" down into the buckets a little so maybe you weree just hearing that or the motor just getting all primed and oily. Mine is a little noisy at cold startup too, but after a minute it quiets down to normal noise levels.

OK, I will admit it. I had, what sounds like, the exact same thing. It happened very briefly, within a few minutes of starting it the first time after the valve clearance adjustment.

Same as you. VERY carefull measurements (three times with metric feeler gauge). Used Dinqua's calculator and Moe's spreadsheet, plus my own spreadsheet. 6 out of 8 shims were changed (3 out of tolerance -too loose, 3 on the very edge -2 were on high side, 1 on thin side). New shims were essentially a shim size different. My micrometer measures down to .005 mm and it's digital.

After seating and installing shims/buckets/cams/caps/bolts (liberally oiled all parts with fresh oil), I reassembled and rotated engine by hand several times. Checked clearances, all properly within tolerance. Assembled entire bike, started (up immediately), ran at higer throttle than idle to get oil to flow (oil light not on). Took a very short spin (50yd). During that run (I wasn't being too gentle either) it did have a short lived hammer sound. At first I thought maybe I was in-between gears. I'm still not sure exactly what it might have been.

I have 700 miles on it since the adj. (2003 TA) and the valve train is quieter and gas mileage has improved very slightly. It's running very nicely (totally stock minus AIS). Check done at 12,900 miles, have 13,637 on it today.

New plugs (NGK Iridium DPR8EIX-9), oil, and filter during adj.

What I would NOT do next time, is drain oil before doing the adjustment. I did, and it was three weeks or so by the time I received all the necessary parts to reassemble. I probably spun the motor by hand a dozen or more times and might have pumped out the oil pumps (they must be primed before installation per the manual). However, I never did see the oil pressure lamp come on. So who knows. If a piston wacked a valve, I'd have to believe it'd be all over. I don't know how a valve with a stem at the angle these are, could survive such a strike.

In any event, I did look over the bike. No I did not open it back up. I was confident in the measurements enough to know they wouldn't have changed much (plus new shims were not drastically different). All shims were 'snapped' in to the buckets firmly before re-installing. Everything including all bolts, caps, dowels, etc went back into the same position. All female and male threads were cleaned and oiled and great care was taken not to allow anything drop into lower case.

I did re-check torque on all cap bolts, but next time I will rotate engine to remove tension off left side cylinder and recheck (10Nm).

Jay

Thanks, Jay. I changed my oil and plugs after valve adjustment. Had old oil in it while turning over engine by hand, even checked plugs to make sure they didn't give me some kind of extra long ones. I think mine is fine, too. The one thing I'll do different next time is drain carb float bowls. By the time I tried to start it, engine was flooded and bowls dry.

Heck, I thought we might have a common circumstance! I was sweating it out and didn't travel too far. After 700 miles and no issues, I'm guessing everything is seated well. One of the exhaust valve clearances of mine was .34mm. Very loose. You could hear that one rattling away. I'll be curious to see the measurements at the next interval.

There has to be an explanation for the noise. I reasoned everything was ok by reviewing the measurements and since all but two shims were only 1 size (.025mm) different from the originals I decided to leave well enough alone.

When you rotated the motor by hand with oil in the case, did oil get pumped up into the head? If so, was it manageable or did it make a mess?

I have to believe this isn't the first time this has happened. I'd love to hear a Triumph tech instructor/mechanics take on it.

Jay

When I turned engine over, first with starter and then by hand as fast as I could, oil pumped through the cam bearings and came out of the cam cover bolt holes. It pumped out faster than it drained back down and ran down all over the engine. I cleaned it up as best I could. When I started it, bike smelled like one of my old 60's Chevrolets I had when I was young, that burned oil smell. Brought back a lot of memories.

Lon,
When you pulled the cam cover back off to inspect the top end, did you notice if the banjo bolts still had their heads? Just a thought (a scary one at that). I still have no idea what would have caused the noise. I was thinking maybe if a banjo bolt head came off it could have sounded like that. But (1) I would expect serious damage would have occurred and would be very visible, (2) A bolt head would break off during installation not later.

Well a local independent mechanic (works on old BSA's, Triumphs, BMW, Norton, etc) recommended leaving it alone since it's running perfectly.

j

I was careful with banjo bolts because I've heard of them breaking off during removal or re-installation. Mine came out real easy. Just put another 80 miles on the clock, thing runs great, nice and quiet. Just went up a tooth on front sprocket, changed the whole personality of the bike.

My banjo bolts came out easy too. If I remember right the torque spec on them is 8Nm, not much at all.

You didn't lose too much off the line acceleration did you with the extra tooth? I always thought I'd keep the stock front sprocket because we ride two up often. I like having the power when I get in the throttle.

j

I ride two up occasionally, so together we are about 400 lbs. I have to use the clutch a little more off the line, especially on a hill, but other than that it's just slightly different shifting, that's all.

When I first changed sprocket, it seemed to lose quite a bit off the line. Now, about 200 miles later, I'm more used to it. Definitely better for me, as I do a lot more highway and not so much in town. Haven't balanced carbs or fine-tuned screws since valve adjustment, doing that tomorrow. With taller sprocket, need to get as much out of low RPMs as possible.
EDIT: Sorry, Dinqua, I meant throttle position.

Lon,
After you heard the hammering noise, you pulled off the CAM cover. Did you notice any damage at all or 'missin parts' like a banjo bolt head?

Even though mine is running better than ever since the valve lash adj. (800+ miles now), now I'm thinking I should go through the trouble and pull the cam cover just for peace of mind.

jay

Nope. Started bike up, everything normal, after a short time, tapping sound gradually starts, gets louder and louder, I shut it off and pulled cam cover. Check, re-check, triple check everything. Rotated engine with starter for a little while, by hand for a long while, didn't find anything. Checked torque on cap bolts and oil tube banjo bolts. Back together, started it up, tapped for a short time, sound faded, everything fine. Balanced carbs today with new guages, runs better than it ever did. 332 trouble-free miles so far.

Well that makes me feel better. After putting another 30 or 40 miles on it today. I put it on the lift to prepare to pull the cover. I still might say the heck with it. Before I put the cam cover back on, I double checked my cap and banjo bolts. 10Nm for the cap bolts and 8Nm for the banjo bolts. All was well. Like I said, my only fear was a banjo bolt head coming off after re-assembly. But I can't convince my self that would have happened. I would think i would have felt the bolt 'soften' up during torqueing. I have to admit, 8Nm isn't much. Those arent under mechanical pressure, only hydraulic I'd think.

Wouldn't you'd think if a cam was receiving none or far less lubrication, you'd know it real soon?

ride on!!

j

I now have 1,000 miles since the valve lash adj. No problems, plus gas mileage seems to be slightly better. Spoke with a Triumph rep (Peter) and he had one idea, he thought it might be shims or buckets settling/seating. He felt since I've gone 700 miles w/o a problem then let well enough alone. I'd bet a mechanic who has a lot of experience with these bonnie motors might know exactly what the noise was.
I'd re-classify the noise as a 'clattering' sound more than hammering.

Any how, when I reach the next interval at 24K, I'll try and find this forum subject and update it at that point to report what things up top look like.

running sweet and strong,

jph