Sticking valves in head

[GoldWingrGreg]

I posted a video today on youtube. Sometimes, noises are hard to capture, and this is an example of such. Here are the symptoms. It's a 2001 that's been sitting on it's center stand for about 6mths on a battery tender. The owner starts it weekly, and allows it to run until the temperature gauge moves to the center mark. He reports SeaFoam was added to the gas months ago. While it was in his garage, he's heard the noise for two startups, so I did a house call.

What I heard was a loud snapping noise like plug wire arching to ground. While cranking it was slow turning over. Once started, there was backfiring in the exhaust. The snapping noise was only there for a few seconds. After 3 more starts, it is now gone. The video captures 2 snapping noises as it is turning over at the 3 sec. mark.

His noise is caused from a sticking valve.

 

[GoldWingrGreg]

Update

After capturing the above video, the noise went away. In spite of my recommendation, the customer chose to assume that the noise was gone for good, but today it reoccured. This time I was able to pull the FI/IGN fuse to turn off the ignition system and fuel system, and re-capture the noise on a 2nd video with the FI and IGN system disabled. Keep in mind that the noise is inconsistent and being able to capture any video takes luck.

My customer has now authorized further diagnostics. It's a good thing, because not knowing what's actually causing it can lead to catastrophic failure ... valve fully open and colliding with a piston !!!

 

[GoldWingrGreg]

I've since pulled all buckets and shims under the right cam. I was looking for the obvious ... a valve keeper or shim that had dropped out of place ... no problem found. However, with my thumb, I was able to push in on all 3 exhaust valves but not the intakes (intake and exhaust valves springs are the same, so the effort to push open all should be the similar).

Once I found no shim or keeper out of place, I reassembled and measure valve lash. What I'm looking for is an excessive wide gap indicating a valve is bent or not completely closing ... nothing stood out.

I then took a compression test on all 6 cylinders. While cracking for a compression test on #5, for a second, I heard a similar "snapping noise" from the left head. Compression was good on all 6.

Thus far, there is mounting evidence that the intake valves do not want to move open (hard to push open compare to the exhaust valves), and once open, some or all are slow to close (snapping noise). Nothing yet to indicate that there is a bent valve; however, next I'll do a leak down test to know more.

 

[Sidecarbill]

Maybe he's using a fuel additive thats causing varnish to build on the valve stems? We did have a fuel injection cleaner may have helped that.

 

[2006gold]

Maybe he's using a fuel additive thats causing varnish to build on the valve stems? We did have a fuel injection cleaner may have helped that.

A common ailment with lawn equipment left sitting too long without proper pre-storage preparation. I've seen the condition bend pushrods. Sea Foam is pretty good stuff, so I'd be surprised if that is the culprit. A stuck intake valve would result in a 'no compression' condition.

 

[GoldWingrGreg]

I doubt SeaFoam caused this ... it's the ethanol in today's gasoline. As for an additive, its my understanding that there is no product on the market today, that can be put in a fuel tank, that'll keep the ethanol in fuel from getting "sticky" over time.

The best one can do is to follow the "storage" instructions in an Owner's Manual.

Owner's Manual > index > storage > motorcycle > preparation for storage.

Then, when bringing it out of storage.

Owner's Manual > index > storage > motorcycle > removal from storage.

 

[GoldWingrGreg]

A stuck intake valve would result in a 'no compression' condition.

You're correct ... if I could change the title, I'd edit it to "sticking valves in head" or "snapping noise while cracking."

 

[FuzzyWuzHe]

if I could change the title, I'd edit it to "sticking valves in head"

Done

 

[GoldWingrGreg]

Done

LOL ... thanks, but it now says "sucking valves in head" not "sticking valves in head."

 

[FuzzyWuzHe]

LOL ... thanks, but it now says "sucking valves in head" not "sticking valves in head."

fixed ... :blush:

 

[GoldWingrGreg]

Update ... after further testing, there's no evidence of a bent valve. However, 4 of 6 intake valves are hard to push in by hand. There are 2 ways this can be fixed. The best way, because it is safe and the outcome extremely predictable, is to remove both heads and send them to a machine shop where the valves get removed, the guides and valves cleaned and inspected. Once the valves are removed, any reputable machinist will require the valves and their seats be ground, and new valve seals installed. Of coarse the cause, contaminated fuel, must be addressed too. Unfortunately, such a repair will quickly add up well over $2000.00.

Or ... I can try and out-of-the-box repair. This method uses a chemical to clean the valve stems. SeaFoam now makes a combustion cleaner that is squirted at the base of the throttle body with a running engine. It supposedly helps clean the combustion area as well as the intake valve stems as it travels into the combustion area. If this works, it's a cheaper solution, but it comes with risks, and the out come not as predictable. Since the dispensing of the cleaner it is done while the engine is running, if any of those 4 intake valves hands open to long, a piston can hit a valve hard enough to bend it, and then a "forced" valve job is required. However, worst case scenario is probably just that, but one always has to worry about unpredictable catastrophe. Cleaning out the contaminated fuel so it doesn't happen all over again must still be addressed. Trying it this way is about $900.

After trying the SeaFoam method, I was left with 1 intake valve that would not spring closed by itself (#5), and I was not able to open it further by hand. I remove the injectors and shipped them to a professional injector cleaning company in Kansas. The injectors squirt directly above the intake valve stem, and with them out, it allows for some access to the stem.

After the SeaFoam cleaning, the stems still had large, loose particles of black carbon on their exposed stems. A few shots of carb cleaner, the stems looked shinny. With #5 I shot the stem with penetrating oil and let it soak. It would still not free. After making sure the piston was down, I lightly tapped on its bucket with an aluminum drift and it started freeing. I believe "mechanical" everything should now be good with the valve train.

Today I'll be emptying the fuel tank, flushing the fuel pump with clean gas, and cleaning the fuel lines. The injectors have been cleaned and are in route back.

 

[tfdeputydawg]

I posted a video today on youtube. Sometimes, noises are hard to capture, and this is an example of such. Here are the symptoms. It's a 2001 that's been sitting on it's center stand for about 6mths on a battery tender. The owner starts it weekly, and allows it to run until the temperature gauge moves to the center mark. He reports SeaFoam was added to the gas months ago. While it was in his garage, he's heard the noise for two startups, so I did a house call.

I always thought this was a no-no? For eons, I have run the tank almost empty, put in the proper amount of either Stabil or Sea Foam, filled the tank, run the bike about 10miles or so to ensure the mix is completely through the system, parked the bike and plugged in the battery maintainer. Never started the bike until in the spring and ready to ride for the warm weather.

Always thought doing what this owner did caused condensation in areas one doesn't need it!!!

Not sure if this is part of the problem but, again, why would one start a bike if it's not going to be ridden?????

Also, being a 2001, how many miles are on the bike??? Stored in heated area or not????

 

[GoldWingrGreg]

The owner starts it weekly, and allows it to run until the temperature gauge moves to the center mark.

I always thought this was a no-no? For eons, I have run the tank almost empty, put in the proper amount of either Stabil or Sea Foam, filled the tank, run the bike about 10miles or so to ensure the mix is completely through the system, parked the bike and plugged in the battery maintainer. Never started the bike until in the spring and ready to ride for the warm weather.

Always thought doing what this owner did caused condensation in areas one doesn't need it!!!

Not sure if this is part of the problem but, again, why would one start a bike if it's not going to be ridden?????

Also, being a 2001, how many miles are on the bike??? Stored in heated area or not????

The ODM says 85k.

I'm sure everything he's done has contributed to this issue. It is stored in a non-heated garage, and here in Florida it's hot. I too believe that running it weekly probably didn't help. However, the real issue is probably ethanol in todays gasolines, and the fact that we have an opposed engine with valves that sit horizontal, and directly below the injector. About 2 years ago I repair another one like this but his damage included the repair of a bent a valve. The rider reported that he rides it daily, and insisted that the longest it had ever sat was for 3 weeks about 3 weeks prior to needing a repair. It too was a FL bike.

To my knowledge there is no product on the market today that one can put into a fuel tank to stop this from happening. The best one can do is to follow Honda's instructions in the Owner's Manual as started in post #6. I know it sound excessive ... but taking care of things correctly often is.

 

[Sidecarbill]

There were a lot of problems with the additives in gasoline in the early 80's. I worked on on few chrysler 2.5s there was so much build up on the valve stem it looked like someone had slipped a cork over them. Amazing they ran at all. These cars never stuck a valve, if you think about it why would they. The valve is constantly moving in the guide. Doesn't make sense. The intake always pulling a vacum so it would seem like oil coming down the guide might be the culprit. The way he starts and runs it doesn't seem it would get the valve hot enough to burn something on there. Just throwin it out there cause seems odd to me that this would happen.

 

[GoldWingrGreg]

The valve is constantly moving in the guide. Doesn't make sense. The intake always pulling a vacum so it would seem like oil coming down the guide might be the culprit.

No mechanic who's had one of these, and who I've talked to knows for sure why this happens. These repairs are far and few between. In my 10 years, I've had 3. Contaminated fuel is everyones best guess.

I've always thought it has more to do with an engine coming to rest as it's being turned off. The reason for that is because it usually affects cylinders #5 or #1. The odds #s are on the right head. Maybe #5 or #1 injector squirts just as the engine comes to rest with an intake valve not closed, and now the ignition is off ... no spark with a wet stem.

The other possibility that I can think of is a leaking injector. However, the report I got back from the injector-cleaner-guy was that "there was no evidence of a leaking injector. 2 were very dirty."

Another factor could be this ... a Wings stored on a side stand vs a center stand.

I just realized in post #11 I was referring to cylinder #6. I corrected that post to cylinder #5

 

[Jack Klarich]

I've always thought it has more to do with an engine coming to rest as it's being turned off. The reason for that is because it usually affects cylinders #5 or #1. The odds #s are on the right head. Maybe #5 or #1 injector squirts just as the engine comes to rest with an intake valve not closed, and now the ignition is off ... no spark with a wet stem.

If that statement stands alone, could u not verify it by removing the injectors, disable the ignition, crank the engine thru 2-3 cycles and look for the leaky injector (S) plural?

Also would u not have a bit more gas in the oil?

I am very leery of Techron and a lot of other additives. I have seen some engines ruined (rings and valves) from TOO much extras added to gas to modify it from the ALCOHOL Uncle Sam provides 4 us. Oil coking on valves was a common problem, ask a Ford tech. Ford used sloppy valve guide interference for oil to run down the stems to help cool the valves and lube the guides . Factor in the thin valves and U had real problems. JMO Hope u beat this one 4 your customer, Good Luck I will be reading

 

[GoldWingrGreg]

If that statement stands alone, could u not verify it by removing the injectors, disable the ignition, crank the engine thru 2-3 cycles and look for the leaky injector (S) plural?

Also would u not have a bit more gas in the oil?

I am very leery of Techron and a lot of other additives. I have seen some engines ruined (rings and valves) from TOO much extras added to gas to modify it from the ALCOHOL Uncle Sam provides 4 us. Oil coking on valves was a common problem, ask a Ford tech. Ford used sloppy valve guide interference for oil to run down the stems to help cool the valves and lube the guides . Factor in the thin valves and U had real problems. JMO Hope u beat this one 4 your customer, Good Luck I will be reading

In this case, the injector cleaner guy said he was not able to verify that one leaked ... therefore, I think you mean a squirting injector as it comes to rest. Yes ... I could possibly do your test. However, you sound like you're a professional mechanic too. Like you I'm in no way a fan of additives for anything. Additives seem to be a DIYr thing ... or a suggestion from a lower level mechanic, or a tire buster, or lube tech., or an installer level mechanic thing, or because the parts man suggested it. Usually higher level techs, will not recommend such stuff unless they understand the problem and have personally verified the results of trying an additive ... which is completely different then just "believing that it's ok ... or because the bottle says to ... or John does it, so I'm gonna too."

Although I'd not considered this, but are you thinking that these sticking valve problems might be caused by an additive, which it could be ... the cause might be staring me in the face ... LOL !!! I always advise my customers that no where does Honda recommend an additive in their tank. Actually, I've not read where Honda recommends an additive anywhere.

Thanks for the brainstorming.

 

[GoldWingrGreg]

The injector's came in. Here's the report. Hopefully the top one is a better image.

 

[GoldWingrGreg]

My "out of the box" checking and repairing worked. Unfortunately, it's labor intensive:

checking

- doing a compression/leak down test

- removing the cams to verify that the valve keepers have not fallen out (if so, it's a strong indicator that the valve is bent near the keeper - it may still have full travel)

- checking to see if the intakes valves can be moved by hand pressure, and they spring back closed by themselves

- checking fuel pressure

repairing

- SeaFoam combustion cleaner following the instructions on the can

- checking to see if the intakes valves can be moved by hand pressure, and that they spring back closed by themselves

- further cleaning and lubing the intake valves with the injectors out

- having the injectors professional cleaned

- removing the fuel tank, old gas, cleaning fuel tanks and lines

- replace spark plugs

- valve adjustment

 

[jjvw]

something to consider: If one has been running too high an octane than what is required, incomplete combustion may cause a sticky valve. In our regular gas Road Stars, we call it "SVS" sticky valve syndrome caused by too high an octane. I don't know what octane is required in your engines.



Case in point: Years ago when I raced sports cars, we had a novice racer blow up her high performance engine. Being low on funds she stuck a stock bottom end under her old modified head. Her practice session went well but when it came time for the race the next morning it won't start. Several race mechanics volunteered (did I mention she was cute) and took off the valve covers and found the valves were stuck. It took lots of carb cleaner poured in the guides to get them unstuck.

When she changed motors, she hadn't changed out the race gas in the tank.