What would cause a valve to bend?


I have a Honda EM5000S Generator that I'm going to ship to Puerto Rico. I bought it used 5 years ago and it worked fine. I never lost power so I never used it. I did let it sit for 5 years with a 1/2 tank of gas. Fast forward to yesterday, I drain the fuel and bring it to a Honda dealer to give it a full service. Spark plug, oil change, air filter, carb/fuel tank ultrasonic clean and flush. $360 for everything. I get a call this morning asking if I could bring in the key. The service guy mentioned something about how they were able to get it started without the key but to do full testing they need the key. I tell them I'll be right over with it. I get a call 2-3 minutes later saying that he misspoke and that they did NOT start the generator but to bring the key in as soon as possible and that the tech found something "interesting." I bring the key in. That's when he starts trying to explain how a valve was stuck and they had to spray lubricant on it and tap it to get it to move and that's when they saw it wasn't seating properly meaning that it's bent. They estimated that it's going to be a 4 figure repair. He also started pulling the whole con mechanic routine with the "your air filter disintegrated, there's mold growing on the inside of the air filter case" and proceeded to talk for 2-3 minutes straight about the bent valve and the backfiring and a bunch of tech mumbo jumbo that I don't remember. While I understand the basics of how an engine works I'm not knowledgeable enough to follow a bunch of tech talk. More importantly I know what this feels like and I feel like I'm getting conned. Here's what I think happened:


The valve was stuck for sitting for 5 years.

I bring it in without my key, they use one of theirs and try to start it.

The valve bends.

Then they call me and mistakenly tell me that they got it started but will need my key to do a proper test.

Then they call me back to backtrack on getting it started because they don't want to admit that they fucked up by starting a machine that they knew had sat for 5 years.

When I bring my key in, the service guy made a point that "that looks exactly like our key!"

I think their key worked, they started a generator with a stuck valve, bent it and are now trying to cover their ass.

Service guy proceeds to point out every minor flaw they found and bombards me with tech speak knowing the average person can't follow along but ends with "we stopped the work because there's no point in completing the service if the valve is bent."

Now he's going to quote replacing the valve, replacing the piston, and replacing both. He's telling me it'll be at least 4 figures.


I feel like they fucked up and are trying to put it on me. What do you think?


ETA: I specifically asked the service guy before I brought it in if I should try to start it. He told me NO. When something sits for that long with old fuel starting it would do more harm than good. Taking his advice I did NOT start it and they knew additional measures should be taken before attempting a start. They also confirmed when I dropped off the key that the carb was in the ultrasonic cleaner which means they started it with a dirty carb earlier.

This message has been edited. Last edited by: Hildur,

Sounds suspicious but hard to tell from here.

If I had an engine that had been sitting a long time and any concern that something could have been stuck, I'd pull the plugs and turn it over by hand first.
The only way to get a better idea of the cause would to be there when the head comes off to see if they may have dropped something into the carb or spark plug hole to cause this.
Another item to check would be the valve stem itself to see if its corroded/rusted enough to have caused this.

I'm pulling the generator and bringing it to another shop to get a second opinion. The 2nd guy says he'll open it up and tell me right away if the damage was done recently or not.

A third the price of a new motor for $40 in parts and an hour’s labor. Northern Tool sells the generator version of the GX390 for $940. The iGX390 is the same motor, but has some extra "intelligent” features over the GX390, so it probably costs more than $940.

Hopefully the second guy has good news.

In the future, draining the tank, running the carb dry, and fogging the engine would have avoided this.

How were they supposed to know it had a stuck valve?

quote:

Originally posted by F12517:
How were they supposed to know it had a stuck valve?

I wouldn't find it unusual if the gas had gunked up the fuel system under these circumstances to a point it ran poorly or even wouldn't start. That would not cause a bent valve.

Unless there's a lot more issues where and how it was stored, I find it highly suspicious that a valve was seized so tightly in the guide at all, much less so tightly that it resulted in the claimed damage.
Most likely cleaning the fuel system, the part he brought it in there for in the first place, would require removing the fuel tank and carburetor to properly clean them.
To "stick" a valve so tightly would normally indicate it was stored in some extremely humid or wet conditions so it rusted in place.
A more plausible explanation would be that they dropped a nut, washer, or some other item into the open intake port or spark plug hole and it lodged the valve in an open position, causing the damage.

I suspect that's the OP's question too. I'll be curious to hear the second shops opinion.

Quick update. I brought the generator to a recommended place to get a second opinion. Like many other places in our country there's a shortage of small engine mechanics so he's going to get around to it as soon as he finishes up some other jobs he's in the middle of.


Here's my understanding of what should have happened:


Whenever an engine sits for a period of time oil dries out, things corrode/rust/stick and the first step is to remove the valve cover, spark plug and then turn the engine over manually to visually inspect. If anything is stuck or not moving properly the tech should immediately stop turning the engine, diagnose and fix it.


The way the dealer described the problem (and wanted to price the solution) the best guess we had on our end was that the intake valve was stuck open, someone tried to start it and the piston hit the valve while it was stuck open and bent it. The dealer swears this did not happen, that they did the procedure above and when the valve was stuck, they put penetration solution on it and unstuck it after "tapping" it. After it was unstuck they noticed that the valve did not close completely which is why they thought the valve was bent and priced it out a replacement (even though it can be cleaned and adjusted).


We'll see what the 2nd guy has to say about it when he takes it apart. Thanks to the feedback/input. It never ceases to amaze me how much knowledge is lurking around these pages. I also thought it was interesting that I could buy an entire replacement engine and have it installed for less than the valve replacement. Another reason why I stay away from dealerships whenever possible. The only reason why I bought it there is because I knew this unit was serviced there by the previous owners, it's right down the street from me and it was supposed to be simple maintenance. Also, I figured if the dealership knew the history they would be more accommodating if there were any major issues considering they serviced it regularly before I bought it. $1000+ for a valve replacement? So much for that theory.

Freed the valve by "tapping" on it. Likely with a 4lb. sledge! Shoulda had a Shooboy on hand (although, vigorously applied, that might even be too much hammer)!

I don't want to be distracting. But I have never seen a used generator that sat for 5 years come back to life for less than buying a running used generator can be purchased everywhere. For sure the carb is junk, the fuel tank likely junk, the engine possibly junk, the gen set itself is possibly junk depending on the moisture level where stored. If in the end you are going to try and depend on this generator stop. Go buy a good used one ($500 on one of the boards) or more realistically get a new one for your new adventures ($600 for a clone, $2500 for a genuine honda). And having said that its likely if you get a new one in PR you can have a dealer that will like and service you.
YMMV of course but I don't see an economic path to a reliable future.

Here's the final update: it's junk but not for the reasons you may think!


New guy confirmed a compression issue with the intake value. He quoted me $150 to tear it down and find the cause. Of course I gave him the go ahead. At 9:30pm last night he sent me a video showing the unit 75% taken apart. According to him everything looked good except the intake valve. Piston good. Head good. Fuel tank good. Carb... GOOD! Only issue he saw was that the intake valve would not shut all the way. He had a spare valve and quoted $600 to do the whole job. I asked if the valve was bent or if it needed to be cleaned and adjusted. He didn't reply.


I got a call from him this morning. He knows I have a deadline to ship it so in good faith he went ahead and replaced the valve so he could surprise me with a working unit in the morning. Unfortunately he couldn't get it running after working on it till 2am. Even though the carb looked good, he rebuilt it. He receded the values and checked the flywheel key (because it was backfiring through the exhaust and carburetor). He believes there's a problem with the timing of the gears inside the engine and to try and fix that would cost a lot more than buying another unit, new or used.


It's disappointing news. Honda engines are supposed to be bulletproof and of all things I didn't think the timing would the culprit. If it was just the valve issue, his cost was at least 50% less than the dealership. Sucks that between the purchase price, the diagnostic fees from Honda and this guy I've spent $1500+ on a Honda generator that I can't take with me. Fuck it, move on.

Man that sucks. I have had an EU2200 for a number of years. Never had a problem, but we lose power a lot, so it never gets a full year without a few hours on it. Sorry to hear of the problems. Disturbing.

quote:

Originally posted by hrcjon:

if you get a new one in PR you can have a dealer that will like and service you.

The situation may very well have changed, but when I moved to Puerto Rico (57 years ago), items like this were priced outrageously high, due to the tax structure for importing this type of thing. Everything that was shipped from the U.S. mainland with my household goods, was tax-free. So assuming that the situation is unchanged, Hildur is better off buying one here and shipping it with his household goods, rather than buying one in P.R.

quote:

Originally posted by hrcjon:
I don't want to be distracting. But I have never seen a used generator that sat for 5 years come back to life for less than buying a running used generator can be purchased everywhere.

My sister has one right now . Her husband stored it in their garage years ago . It needed new fuel lines , filter , and a carb overhaul . Less than 200 bucks all in , labor included .

quote:

He believes there's a problem with the timing of the gears inside the engine

Dumb question, but what would have caused it to go out of time??

Seems like storing it wouldn't do this.

That's a $2500 generator. Its worth fixing.

The motor, brought to an ACTUAL mechanic, would be fixed for not a lot of money. Since you are having trouble finding competent mechanics... another option is to buy a used generator with a Honda engine on it, and swap the engine. I find used generators all day long for $100-$400.

Its fixable. I wouldn't junk the powerhead. Its a Honda, and its amazing.

These Honda engines DO have a foam filter element and they do disintegrate into dust after about 5 to 10 years. So he was probably being truthful about the air filter. The air filter sucks on these and you must replace them every couple years.

quote:

Originally posted by selogic:

My sister has one right now . Her husband stored it in their garage years ago . It needed new fuel lines , filter , and a carb overhaul . Less than 200 bucks all in , labor included .

That's what I was expecting. The original quote from Honda was $150 for a tuneup + another $180 if they had to clean the carb, fuel tank and lines. I was ok paying up to $1000 because it is a $2500+ generator, I bought it for $800 5 years ago and to put another $1000 now is still cheaper than any comparable generator.

The 2nd guy is definitely competent, he's been doing it 35 years and not one but two friends of mine who are mechanics highly recommend this guy. Perhaps there's more to it than what he told me. At the end of the day I trust him. He put 7+ hours into it plus parts and when he couldn't get it working he gave it back to me intact and only charged the $150 fee that I agreed to. I know of another Honda EM5000S for sale a few hours away and he wanted me to keep this unit as parts... I told him no way. I'm not lugging two 250lb+ generators to Puerto Rico. I told him to keep it and use the parts himself to make up for the time he wasted on it. If his goal was to con me that's one hell of a bluff giving me back the unit.


I'm sure Honda makes a great engine but based on my experience with their dealership and their generator/engine, fuck them. I'll buy a new generator from the next best competitor for half the cost, much better technology and fuel economy.

quote:

Dumb question, but what would have caused it to go out of time??

Seems like storing it wouldn't do this.

I don't know. I had the same question but I'm running out of time and ultimately it doesn't matter. If this guy couldn't fix it in a cost effective manner then no one could.

quote:

Everything that was shipped from the U.S. mainland with my household goods, was tax-free. So assuming that the situation is unchanged, Hildur is better off buying one here and shipping it with his household goods, rather than buying one in P.R.

From my research this is still the case. However this generator was a beast weighing in at over 250 lbs. The cost to ship on a pallet was probably $150-$200. I can buy a 4000-6000 watt generator for under $1000 and the tax would be no more than $115 so in this particular instance I'm better off just buying local. During the last hurricane I had a small 2500 watt suitcase generator. It powered 4 things: my refrigerator, my laptop, cell phone and a fan. I'm simple. The only reason I wanted to bring the Honda is because the Ryobi would overheat when running it for long stretches and the Honda should have fared much better. Oh well, put this L with the rest of them.

Here’s a video where a guy tears down a Honda GX390 in 30 minutes: Honda GX390 Disassembly

The camshaft has an integral gear that’s driven by what appears to be an integral gear on the crankshaft. Integral as in one piece. If true, the only way the timing could be off is if someone split the case, removed the camshaft, and didn’t align the dots upon reassembly. Spark is generated by a coil mounted over the flywheel. There’s a big magnet in the flywheel and when it swings past the coil an electric current is generated cause the spark at the spark plug. The timing here is determined by the flywheel and crankshaft. Both have keyways machined in them and the key keeps them aligned. If the ley is intact, there can be no timing issue here.

I’m going to guess backfiring through the carb is from the intake valve not seating properly. Thos is the part two different people have supposedly touched. If the generator worked for Hilder in the first place, nothing happened in storage to mess up the timing.

Give it to the high school autoshop and deduct it on your taxes.

What's your timeline for departure to PR? I semi-local (about 25 miles to the north) and might be able to help. If the timeline is too tight, and you're looking to offload it I might be able do something with it.

nhracecraft, that's an incredibly generous offer. At this time I won't take you up on that but if you want to come down, do some shooting (I'm a member at Pelham Fish and Game) and have a cigar/food/beers afterwards before I tear my furniture down and pack everything up let me know. My email is in my profile.


I texted the guy this morning about getting the unit back and here's what he said:


"I took it all apart. I was going to fix it and call you. I went even deeper into it. I already ordered the parts for it and it is completely apart of my bench again. I felt bad and I didn't want to see you lose it.

The cylinder head was warped. When the job is completed it will be $450 for a final payment. Not only that, I didn't want to lose all the time that I have into it."

(I thanked him and offered him lunch)

"No, thank you very much. I felt so bad the other day when you had to leave the generator, I am the type of person that will not give up. I knew when you left I was going to give it a second shot and surprise you.

The cylinder head will be here Monday. I am going to try to get it done by Tuesday for you.

The way I found out what was wrong is I made a tool and pressurized the cylinder and air was coming out all around the head gasket so I took the head off and examined it. That is definitely the problem. I am saving the old cylinder head for you so you can keep it as a conversation piece haha.

I felt so bad that you not only paid me $150 but you left the generator as well. I am not the type of person who will sleep at night thinking about how much you lost as well as me.

I really enjoyed talking with you the other day. You are way beyond knowledgable and it's nice to talk to people who make sense. If I didn't have such a big family I'd sell my house and be your next door neighbor in Puerto Rico. I can't get over the beautiful pictures you showed me.

As for your tractor and snowblower you can bring whichever when you come to pick up the generator. I am confident I'll get them running and will help you sell them if you aren't in the area anymore (my idea). I can put them out front with a for sale sign while I'm at the shop."


I couldn't thank him enough and told him he can have the tractor and snowblower with no strings attached. Now he doesn't want to charge me for the generator but if he can get it running to his standard then I'm incredibly grateful to pay the $450. I was going to scrap the tractor and snowblower after seeing how sitting for 5 years can affect these motors but if he can get them running he should net positive after selling them. With the work he's done and will do, I want him to come out ahead after all the thoughtfulness and kindness he's shown me. He's one of us, thinks like we do and has character and integrity to boot. The world needs more people like him (and nhracecraft, I'm still floored by his offer to a relatively complete stranger).

Now that's a mechanic worth his weight in gold!!