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gzamboni

Valves too tight or something worse?

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Hey guys,

My 93 DR350S engine started making a ticking sound recently, so I checked the valve clearances. Engine is at TDC on the compression strokes and the rocker arms are touching both the intake and exhaust valve springs. Looks like they touch at a weird angle too, like not fully flat against each other (pic included though not very clear). This is my first valve clearance check on this bike so I'm inclined to believe whoever did it last messed it up and now I'm paying the price. Can anyone tell me if they are supposed to touch like that or any insights at all? My friend and I are currently taking the top off the engine and having a look.

Thanks guys

20190701_163116.jpg

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UPDATE: Top cover is off, there is some gouging on the rocker arms... Don't know if it's normal but I attached a picture of it. Cam looks completely fine, chain feels loose definitely needs to be tightened. 

Anyone got any tips, what should I look for now, maybe dig a little deeper and look at the valves?

15620144826355067814867165422621.jpg

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1 hour ago, gzamboni said:

UPDATE: Top cover is off, there is some gouging on the rocker arms... Don't know if it's normal but I attached a picture of it. Cam looks completely fine, chain feels loose definitely needs to be tightened. 

Anyone got any tips, what should I look for now, maybe dig a little deeper and look at the valves?

15620144826355067814867165422621.jpg

From your picture I can clearly see the rockers are seriously worn. I would be very surprised if the cam isn't worn as well. That's why the adjusters don't sit flat on the valve stems. WOW!

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12 hours ago, Bob Losiniecki said:

From your picture I can clearly see the rockers are seriously worn. I would be very surprised if the cam isn't worn as well. That's why the adjusters don't sit flat on the valve stems. WOW!

Yeah, bike's only got 7k miles too... somehow the cam looks completely fine though, smooth and shiny all around. Do you think the worn rockers hitting the cam could be the cause of the clicking noise I was hearing? And do you think I have to replace the rockers or can I just get them machined?

Today I'll be removing the valves from the cylinder head and having a look at them.

Cam, cam chain, piston and cylinder all look good though the chain tensioner is maxed out so I'll be replacing the chain.

Thanks,

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19 minutes ago, plugeye said:

recommend new chain guides & rockers

 

Wouldn't I need to replace the chain as it gets looser over time? The guides look fine to me. Forgive me if I'm mistaken.

Also, I just purchased these: https://www.ebay.com/itm/Rocker-Arm-Intake-Exhaust-For-SUZUKI-DR350OE-DR350SE-350-1990-1999-/202533183199

Kind of pissed I'm gonna have to wait for them to come in from china to get my baby running again :( , but do you think they're any good given the low price?

Thanks

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4 minutes ago, gzamboni said:

Wouldn't I need to replace the chain as it gets looser over time? The guides look fine to me. Forgive me if I'm mistaken.

Also, I just purchased these: https://www.ebay.com/itm/Rocker-Arm-Intake-Exhaust-For-SUZUKI-DR350OE-DR350SE-350-1990-1999-/202533183199

Kind of pissed I'm gonna have to wait for them to come in from china to get my baby running again :( , but do you think they're any good given the low price?

Thanks

yes, if the chain is too loose. look real closely at the guide where it pivots, over time they compress. i replaced my chain & not the guides, but noticed the tensioner didnt improve much with just a new chain. next time i'm in there, new guides. i'd give those rockers a shot.

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9 minutes ago, plugeye said:

yes, if the chain is too loose. look real closely at the guide where it pivots, over time they compress. i replaced my chain & not the guides, but noticed the tensioner didnt improve much with just a new chain. next time i'm in there, new guides. i'd give those rockers a shot.

Thanks plugeye, I'll have a closer look at the guides when I get home. Do you think those worn rockers could be the cause of my ticking sound? I'm thinking it's gotta be that or the valves, everything else is looking good. I'll be taking the valves off the cylinder head today to inspect them. 

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17 minutes ago, plugeye said:

could be, very worn

How could they have worn out so severely so fast and what can I do to ensure that doesn't happen again besides constantly checking my oil level and topping the bike off?

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A crankcase with too much oil will make the oil foam; this makes the oiling system lose pressure while at the same time pressurizing the crankcase and squirting oil into the airbox. Based on the wear and mileage all of this damage may have happened because of too much oil in the engine. How much oil was in your airbox?

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Posted (edited)
9 hours ago, gzamboni said:

Yeah, bike's only got 7k miles too... somehow the cam looks completely fine though, smooth and shiny all around. Do you think the worn rockers hitting the cam could be the cause of the clicking noise I was hearing? And do you think I have to replace the rockers or can I just get them machined?

Today I'll be removing the valves from the cylinder head and having a look at them.

Cam, cam chain, piston and cylinder all look good though the chain tensioner is maxed out so I'll be replacing the chain.

Thanks,

IMG_20190702_153506050.jpg.21a61e15e210eb48370d9344db2a84d5.jpgwith the wear on the rockers your valves aren't opening fully & the valve clearance increased so tapping or ticking would be expected. You need to check your cam regardless of it's appearance.

Intake height 33.430-33.470 mm wear limit 33.13

Exhaust height 33.460-33.500 mm wear limit 33.16

If you don't have a manual for your dr350s that would be a great investment at this point. 

Why do I feel the need to tear in to both my 91's all sudden?  

Edited by Bob Losiniecki
Added text

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Boys I have located the cause of the ticking. Both my intake valves are visibly bent and were a bitch to get off. My exhaust valves look straight and came off easily though I'm thinking I should somehow make sure they're not microscopically bent.

I will get my hands on some micrometers and measure the cam wear.

The new rockers will take a couple weeks to arrive so I'm gonna open up the bottom and check the status of the shift drum bolt. 

Old fart, no air in my airbox I think I was running my girl a little low on oil if anything 😔 won't make that mistake again.

Anyone know how to check the exhaust valves for straightness?

 

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Posted (edited)
53 minutes ago, gzamboni said:

Boys I have located the cause of the ticking. Both my intake valves are visibly bent and were a bitch to get off. My exhaust valves look straight and came off easily though I'm thinking I should somehow make sure they're not microscopically bent.

I will get my hands on some micrometers and measure the cam wear.

The new rockers will take a couple weeks to arrive so I'm gonna open up the bottom and check the status of the shift drum bolt. 

Old fart, no air in my airbox I think I was running my girl a little low on oil if anything 😔 won't make that mistake again.

Anyone know how to check the exhaust valves for straightness?

 

Clymer's manual for Suzuki dr's eBay

Under $30.00 shipped you get all that knowledge at your finger tips. I still look and ask for advice, but I got a better understanding of the answers I get with the manual. It will show how to check your valves and everything else.

I got rockers from China for my 250s and they got here way ahead of expected delivery date. 

It's not surprising at the angle the rockers where hitting the valve stems due to their wear that at that high rpm's it could bend the valves. Good luck

Edited by Bob Losiniecki
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here is an even-older-fartz trick to checking the straightness of those valve stems , from a 2stroke genious that also likes to work on old 4strokers ,

take the suspect valves and place them one by one into a variable speed drill  - chuck them in like a drill bit --BY HAND ONLY-- you dont wanna leave any deformations in the head of the stem ,  with just the end of the stem held in place , turn drill on slowly at first , then increase speed slowly  -  if there is ANY wobble it indicates a bent stem ,, if there is a flutter at the flaired lip of the valve it indicates bent valve hat  (the actual closing portion that contacts the valve seat)   the valve edge portion that contacts the piston head in a catastrophic  head issue  = like a sticking valve stem that prevents the valve from returning to fully seated position        

--OR--    you didnt get the valve inserted straight into the drill chuck --- do a few test runs on each valve  - it is a technique specific test -  if you test each valve 5-7times and you just can NOT get them to spin smoothly  THEY ARE BENT   bent stems are easily spotted with the drastic wobble ,, the bent lip is a tough one you really need to stare at that spinning edge with great concentration   -- almost samuri like 

so which came first ????     the bent stem causing the valve to hang-up   or   the bent lip  that allowed overheating of stem and sticking ???????

good luck   rebuilding 4stroke is NOT    brain science    or  rokit surgery    even I can do it and I am a one of those deplorable 2stroker aholez 

DDD

 

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BUT the real question is  ???   why did those rockers grind away ??????

how is the oil pump ??   the oil lines ??  the oil gallies threw the head ???

those teeeny tiny passages get clogged with a spec of crud and BOOOOM new top-end needed in a few seconds at normal RPM 

if you have time , take it apart to the base gasket and triple check everything especially those tiny oil passages AND oil pump output pressure , need one of those kooool oil test gauges that screws into the clutch sidecase for testing - low price last forever  can be used on other bikes easily 

like that other dude stated get NEW cam chain guides with the new chain   CHEEEEP INSURANCE   check that cam chain tensioner also 

like many have said before me = take the time to do it right -or- make the time to re-do that halfazzed first attempt 

DDD

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You mentioned coming from China... I would recommend against using Chinese replacement parts if possible.

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sorry to bring home some bad news, but all the hard metal that came off the rockers is now fine grinding grit has been circulating in your oil for a while, most chances is that the oil pump will be scored too. with this sort of damage i'd be doing a complete engine dismantle and check.

cant see the cam bearing areas in the head as its covered in oil, good chance that theyre worn too.

cam is shiny because the metal powder acts as a good polishing agent :(

typical damage done by running oil low/not changing it in time....  if it's as bad as i suspect a used motor could be cheaper than a rebuild.

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Thanks for the tips dan man I'll be using those techniques to check the exhaust valves and will definitely get some oil pressure gauges and check out my oil system.

Bob, I do take advantage of the thumpertalk veterans a little too much I'll admit. I do have a pdf of the service manual that's been helping me but I was looking for some clever ways (like danman's) to do these things as I have barely any tools and don't even have a garage (college student life).

I have canceled my order for the chinese rocker arms and bought some off bikebandit as I realized I shouldn't cheap out on engine components of all things.

Turbo, I really hope that's not the case man :( My bike is young and I've only gotten a few months of enjoyment out of it so far. The piston and the cylinder look fine but I'll definitely be checking the cam with a micrometer. I don't see any metal shavings in the oil or the engine but like you said they could be microscopic.

I really don't want to disassemble my engine any further as this was already pretty intimidating for an extremely inexperienced 19yo. I will be opening up the crank case soon to check on the infamous shift drum bolt and while I'm in there I'll look for any damage too. I'll also check out the oil pump.

Any other ways I can make sure I don't have metal flakes without doing a full teardown?

I'd like to think I'm more or less in the clear as my engine was running like a dream until the ticking started (which only lasted 10 min or so before I shut off the bike) and the worn rocker arms and slightly bent valves explain that but I'm no expert or mechanic.

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Also the ticking started immediately after I took the bike on a stretch of highway for a few minutes, so yeah, high RPM's

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