Generac 10 kVA Generator again.

[WFK]

Somewhere in the electronic archives are my trials and tribulations with this thing, and all the good advice received then. (Basic problem: one of two cylinders fouling within hours of use.)

Anyway, nothing worked, meaning none of the defects suspected could be verified and fixed. And my distrust of mechanics kept me from getting professional help.

Meanwhile I have found that the Generac 19 hp Industrial Engine is indeed a Vanguard 18 hp engine made by B&S, and that B&S sells essentially the same generator under their own brand name.
(The Generac engine ID is stamped with a B&S series ID.)

Well, I had a long talk with a "smiling" machanic at a shop who had enough patience to listen to me. ("I know that engine, it's one of the better ones B&S makes," etc. And yes, he has worked on generator engines before.)

He will get a chance tomorrow to prove his skill.
Either he IS good and then you and I will finally know what the problem was, or he will give up or make it prohibitively expensive to fix, and then we will never know what did it, and I will have 300 pounds of scrap at $6.60/lb.

Meanwhile, solar/battery/inverter are always ready.
typo fixed

 

[Green Co.]

...and do please let us know the doc's prognosis.

I had a similar problem with a B&S 18hp Industrial twin. Couldn't find the problem, ended up with one of the old fashioned, screw-on the spark plug, oil shields.

At least, it would run the mower for the four hours needed to cut the back lot without miss-firing.

 

[Tom McDowell]

I for one am very disgusted with the Briggs V with Generac.

Just brought back the entire gen set (in pieces) back from the shop.

The intitial problem was a leaking front crank shaft seal. After replacment the engine ran another 10 hours (bringing the total hours up to around 25). The seal failed again, the problem was a failing output bearing, which then ruined the crank, which in turn damaged the generator. It seems to be a poor design placing the output bearing in such a fashion as to take the load from both the crankshaft, and, the input of the generator - all on the same bearing.

Generac = Garbage

This 11 kw genset belonged to my neighbor, I wish I could have warned against the purchase before it was made.

BTW the tops of the pistons were covered with carbon, way too much for such little use.

 

[richw]

I've have been a general contractor for 17yrs now and in the field Generac generators have ALWAYS been refered to as general junk.

We could never figure out why a B&S engine on a generac generator would only last about a year, while the same exact engine on a coleman generator or a cambell hausfeld air compressore would run for thousands of hour's with only routine maintenance.

Well after a little research we found out that generac operate's just like sears. They will require the engine manufacturer to either up grade or down grade the mechanical specs of the engine to either cut cost, therefore they can undersell the competition or to limit the life of the item so as to sell more.

The big thing that alot of consumers don't realize is generac is tageting the general consumer and acording to them. If you are using a generator for household back-up power you don't need one that will run for 5000 hrs. or more.

The average consumer will only use a back-up power source for a few hours a year. A generator thet is used for residential back-up power will generally dry rot to death ie. insulation on the wiring,rubber hose's,plastic gas tanks and engine seals. Before they register 1000 hours. Therefore they don't need to be built to run for 5000 hrs.

In all honesty this is why a 6kw unit built by generac only cost's around 700 to 800 bucks and a fairly well built unit for commercial use will cost you $1200. bucks minimum.


As far as your problem WFK If the cylinder is oil fouling I would start checking with a compression test on both cylinders I bet you will find the offending cylinder will be low and if it is, try doing a wet test on it. Get an oil can and put a good shot of oil (general motor oil down the cylinder and see if that doesn't raise the compression atleast 15%. If it does you most likely have a defective set of piston ring's.

 

[Dennis Olson]

There is a lot of information here on the forum about generators. The bottom line is that for a modest-sized GOOD generator, expect to pay about $2000, at a minimum. The Generacs are generaly only for VERY occasional use, and you can expect the engine to be slag at about 200 hours.

(I did a bunch of research on generators in 1998 and 1999.)

 

[WFK]

What this is all about:

Half a year ago I started this thread:
http://www.timebomb2000.com/vb/showthread.php?s=&threadid=50702&highlight=generac

So there has been a significant input from this forum and from OTHER shade tree mechanics: all of the ideas were put to rest in order. Too much detail to report each one. Compression test was one them: equal compression! Swapping magnetos another, done. (Fouling stayed on same side.) Checking for intake air leaks: negative. Checking valve lash (spec).

I did my bitching about how this thing was put together and haven't changed my mind. (I will have to pay the machanic dearly just to GET TO things. )
There is one photo of the two spark plugs that says it all, I will dig. I found it but cannot add it by means of "edit."

 

[WFK]

That was taken a year ago and the experiment has been repeated many times...
These plugs were put in together and removed together when the engine started to run rough.

Specified job for the mechanic: successful repair means plugs look alike after 3 hours running time!

 

[richw]

ok wfk you've definately peaked my cureousity


I took the time and read the thread.

I guess you've got to be about at wits end by now. I do all of our equiptment repairs myself. So I understand what you mean by lack of good repair facilities with trustable mechanics. There are so many repair shop out there now that hire kids direcly out of high school and hand them a repair manual and thier first job.

Trust me when I say every generator out there today are a pain in the a$$ to work on.

They definatly build them for portability in mind now and not eaze of repairs.

I'm going to take a long shot here.

The picture you posted appears to be carbon fouling and not oil.

You have basicly done everything to rule out ignition. So it appears to be air/fuel mixture. I would think vacuum leak. I noticed you check for loose bolts and I assume you checked for leeking gaskets like I think rex had pointed out in your old post.

But have you checked the intake runner itself. They are fairly long and made of cast aluminum. I saw one on a honda engine with somewhat the same problem you are having.

The intake was a pourous casting and after substancial use it developed a very fine hairline crack running rite along the casting line. With that particuler engine when you would first start it it would run great but as the engine got upto running temp. the crack would open up causing a minor vacuum leak and foul the spark plug.

Like I said it's a long shot.


IF by chance you find out that IS what it is let me know. We keep all of our wornout engines around a while for parts. I probably have one here.

 

[WFK]

richw,
You are not the first one to suggest that; a local guy here who restores cars said the same thing. And he said a way to test for this is to spray WD40 on it or carburator cleaner and see if it changes the running speed or sound of the engine. And, BTW he said the leak could be on the side that has the clean plug.

I tried that. But one cannot spray the intake manifold adequately to get everywhere. So I took the whole thing off and inspected it closeup, plugged two ends and blew into the third. Didn't find it, but maybe there is one, then you and the mechanic get the grand price!

I have an indication of an EXTRA bump on the camshaft of cylinder #2 exhaust valve. I can feel it on the push rod. I am alone with that theory, nobody believes me, I myself have no idea how something like that can happen, and I have no way to confirm it.

And yes, it is carbon fouling not oil fouling.

 

[richw]

WFK

You can usualy find the leak with carb. cleaner but the engine would have to be at running temp. I understand what you meen about not being able to spray all around it but spraying the top and letting it run down should work. Cautiously with a hot motor if any hits plugs or wires it would solve your problem and quick.

When you take the intake of and blow thru it unless the crack is large you wouldn't notice it. The crack on the one I posted about was so small it would go closed when the engine was cool. With the casting flash line hiding it from site. We were so interested that after installing the new one and a test run. We cut the old one into sections just to see and sure enough the crack was about 2 inches long but rite nexto the flashing so it couldn't be seen.

As far as the crack being on the good side. I could understand that but you would probably see a little blistering on the porcelin from heat.

I noticed in your old post about the minor lift on the exhaust valve during the intake stroke and just thought possable foreign matter. We had an air compressor that was only making pressure on one of two cylinders and when I tore it down I found the small ring from the top of an oil bottle on top of a valve holding it open.
Makes me wonder if you have something stuck to the cam.

I can't off the top of my head figure how that would cause your problem though.
If exhaust was getting into the cylinder I would think it would show a lean burn due to diluted air/fuel mixture. and with as small an area as the manifold on those engines it would probably ignite the mix causing severe detonation and in a two cylinder engine you would have known it.

no matter what, it is interesting so please keep me posted

 

[WFK]

This is getting interesting even before feedback from the mechanic working on it!
With the info you provided I would have just ordered a new intake manifold on pure chance.
As far as a bump on the exhaust cam is concerned, I hear what I call misfiring after a short time of operation.
First it is just a single explosion in the exhaust, which gets more frequent as running minutes accumulate.
Ultimately it is just an irregular but frequent noise that may happen every second or so. By that time the plug is fouled and the gen output is low and irregular.

If one holds a hand infront of the muffler one can feel the puffs associated with the noise.

I had the pushrods out (exhaust ones are aluminum!) and they looked perfectly rounded at their ends.

Thank you for your feedback! Very much appreciated !

 

[Pathfinder]

Weeelllll..

I'm not much on gensets but..

You might try a cylinder leakdown tester..

See if you might have a burnt valve..

Or if you want to do a poor man's smoke machine???

 

[WFK]

Interim report:
Visited the mechanic today (1 1/2 days passed.)

(He still has that smile of absolute superiority on his face.)

1. "someone cut the idle control lever."
Comment: It's broken for sure. But he cannot distinguish between a stress fracture and a cut... (he should be able to see the difference even without a degree in mechanical engineering.) Pure coincidence, because it ran for three hours at full speed before I took it over there and it needs that lever to run full speed.

2. "junk in carburator."
Comment: What he didn't know and what I didn't tell him was that I had the carburator apart (and clean) only one gas tank earlier and a gas filter put in immediately after that.

3. "Valve clearances not set right. 3 too tight, one too loose."
Comment: I told him about the loose one before he ever touched the thng and explained that it was my last ditch effort to outwit the bump on the 4th cam. So that was no surprise.
I don't recall resetting the others from factory settings because they seemed to spec.

Idle control lever on order... No serious test done yet. (So he is where I was a year ago: somethng easy.)

Told him about possible crack in intake manifold as experienced by
richw. Smile unchanged.

 

[richw]

Hello WFK

Glad to see you got a report (I think)

I don't know about you but I get the impresion your mechanic is like the ones I posted about earlier.

He seems to be running text book diognostic's.

1. "someone cut the idle control lever"
But he can't tell if it's a stress break or a cut HMMMM

just speculation on my part buttt

I've seen guys force the idle control on generator's to atempt to lower the idle. Due to the fact that they "think" it's running to fast.

Most of the idle control links are nothing more than a small steel wire with a hook in the end. On commercial units its a thin steel plate with a stop screw to maintain RPM's


2. " junk in carb"

With a common carb for both cylinder's dirt in the jets would afect both cylinder's not just one. Again it appears he is pulling straws using text book diognostic's instead of veteran nolage.

3."valve clearance's not set rite"
iirc valve clearance is to be set to factory spec's at running temp and slitely looser when cold just to bring the engine to running temp.

If the valves were more than a few thousanth's to tight it would greatly affect compresion and possably evan bend the valve's

 

[WFK]

Confirm:
1. idle control is a wire. I chose the wrong term, it looks like a fatigue break (clean but grainy.)
All that thing really does is change from idle to full speed governor take-over.
2. exactly! He still hasn't understood that what he is looking for is NOT common to both cyclinders. He is too young to be a veteran mechanic...
3. I would vote for the rather long push rods to get bent (especially the aluminum ones) before a valve gets bent.
(And the push rods were straight when I inspected them.)
The compression test (electric starter driven) showed the same compression on both cylinders (original thread.)

And if I were him, I would have bent a wire into the exact shape of the broken one and would NOT have waited for a part to continue trouble shooting! Or I would have brazed the two pieces together temporarily. Well, maybe at $55/hr for his time I am better off if he doesn''t bend wire.

 

[WFK]

Dec 31, no-progress report.

Shop has decided to order all parts (gaskets, linkage, a valve cover -cracked, I did that) from Dixie Supply:
"They are the only ones for Generac parts."
"no use working on it until the parts arrive."

Rant: this is a typical NC shop comment: "we call you when we get to it."

OMG! The last order I placed with Dixie Supply was not filled until 18 months after placement.

Mechanics special:
I MADE the linkage form welding rod!
They still say they cannot run the genny because air will leak into the intake through the cracked valve cover. By the way, I cracked the cover, just when I put it together the last time, I heard it crack.

item 1> the cracked valve cover is unrelated to crudded plug.
item 2> false air through crack is totally BS. Why would the other side have an oil filler plug?
item 3> they have not yet verified or even thought about my original complaint that one plug cruds up but the other doesn't.

I go into the new year with solar backup only and have basically written off this genny. I will have to decide whether I really need a genny.

richw, your suggestions are not forgotten but the genny is inaccessible to me right now until they fix it or give up.

 

[north runner]

Maybe a way out of your quagmire is to find a natural gas/propane conversion kit for it? At least it wouldn't be a total write off and should stop carbon fouling the plug. The only other thing I can think of besides what you've so diligently listed is you're using the wrong plug, or rather that a different plug might work better Specs are only guidelines sometimes LOL

 

[WFK]

Conversion is out for a faulty engine. Your other idea
has already been proven as n/a:
twin cylinder, common carb, only one side affected.
Anything that could be swapped has been swapped.
Fauling stays on same side.

 

[north runner]

Thats funny, I didn't say switch the plug...I said, try using a different plug altogether. Of course that idea would assume your cylinders are unbalanced or different in some way. Let me put it more plainly - one plug for cylinder 1, a different plug in cylinder 2. Longer shorter hotter colder - whatever. No way you're going to turn that pos into a swiss watch.

 

[WFK]

This thing never ran right.
There is the nagging thought that one of my buddies has the exact same generator and he has so far put 168 hrs on it WITHOUT any problems (bad gas once, which caused him some carburetor cleaning work.)
So what I have is not bad design but a manufacturing lemon.
Personally, I like to find causes and resolve them rather than treating symptoms. That is why I have swapped all swappable stuff to the opposite cylinder.

Now, what really annoys me:
1. Personally. I used to write before Y2K that it was imperative to "test everything." Should I have known that this meant an ENDURANCE test for the generator? My fault! The flaw showed up during the first serious outage after warranty had expired.

2. This gizmo is MADE IN USA. Yet there is some feedback that suggest that B&S has not learned to make a good, lasting engine.
By spec this engine has steel sleeved cylinders and is by Generac sold as an Industrial grade engine. This is not rocket science!
Guess what? The next genny will have a Honda engine!
There is nothing wrong with the electrical side of it; it has run my house. So I will throw away the perfectly working stuff because of a lemon B&S engine, made in USA.

3. I KNOW that the faulty cylinder exhaust valve opens a hair at the wrong time, in addition to the time when it is supposed to open. I got one believer on this forum who has seen at least something similar. The mechanic says this engine has a centrifugal valve switch that opens during start for pressure relief.
He showed me the exploded view. For him that meant he discounted everything I had told him. Problem is that the centrifugal switch works on BOTH CYLINDERS and not just one.

Prediction for 2004:
You all will know how this ends.

 

[WFK]

Jan 7, 2004

I BOUGHT the (B&S) parts the shop is waiting for elsewhere (competition's turn around time 3 business days) and MADE the wire hook that is generator specific, delivered it all to the shop (and made my opinion about parts ordering known to the boss.)

1/2 day later (phone call):
The shop has now verified my inital complaint and (after swapping magnetos and setting valve clearances) is as baffled about it as I was!

Labor cost: they will pull the head on the fouling cyclinder, but anything beyond that (like changing a piston or rings) will mean separating the engine from the generator. And that would be prohibitively expensive.

It looks like decison time is approaching.

 

[richw]

If shipping wasn't so high I'd have you ship the thing up here to me.

Half assed know it all's get under my skin.

Sorry about that

If you can, give me a day or two before those idiots pull the head off and run your bill up. I want to research the mechanical compression release on that engine. I've wanted to since you posted last but I haven't had the chance.

If they were anykind of compitant mech. they would know damn well that with good and equal compression on both cylinder's it is NOT a piston and rings problem.

IIRCC the mechanical compression release on that engine operates the exhaust valve ( the earlier models didn't evan have one) and after reading your last post I started thinking about that.

Due to the temp here I should be in my shop most of the day tomorrow and will check to see if I'm rite.

Because if I am then a weak centrifical spring or a bad weight could be causing the switch to hang and open the valve slightly.

I have to say it is a long shot but in theory it's posable.

sorry about the typo's it's getting late

 

[WFK]

FINAL, I think.

They DID pull the head off and I had agreed to that.
I saw it today.

1. the fouling is oil fouling and the piston top shows an area on one side that is NOT crudded. (Actually TWO areas) They say that this is an indication of bad rings and oil blowing up through that area.
2. They have consulted with B&S and they agree.
3. The shop also had measured higher compression on the crudded cylinder and they say that is because the space between rings is oil filled. (That was one of the original mysteries)

Whether it is THIS or the centerifugal springs, the result for further work and expense is still the same: too much labor cost because from here on the generator end and the engine have to be removed from the frame and separated for engine repair.

The whole thing is a write-off.

I want to say that it NEVER ran without oil (and is has a low oil pressure shutdown switch anyway.)
It never ran right over extended hours.
I just didn't count on getting a faulty gen set to begin with.
Repairing it would be to throw good money after bad money.
It is now one of the few instances in my life where I have blown $2k for absolutely nothing.

Although I will never know with 100% certainty, some of the early replies pointed to rings. The valve lift difference and oddity will remain unsolved. Too big a job to tear it all down to satisfy my curiosity.

 

[Tom McDowell]

Wow,

Sorry about the write off. Same thing for my neighbor, the crank spun, ruined the bearings, & crank - started to tear up the generator, the whole thing is in pieces in my shop. Cost $100 for another small engine shop to tear it down. We're now awaiting delivery of a HONDA GASOLINE 20 HORSE POWER GX620VXA3, bought it off line from an ebay vendor
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2582782739

Between the two of us we've enough parts to build a working Brigs/Generac -- Interested?

Best Regards,

Tom

 

[WFK]

Tom,
on 12-08-2002 I wrote:

Generac has been written off by me as do-not-buy-again. I have already found too much objectionable design and manufacturing on this generator.

Much of that criticism was related to:

Gastank didn't quite fit in the first place and was forced to fit
Linkage interference with stationary parts (that linkage ultimately broke into two pieces)
Gasline forced and tied kinked (again: interference)
Muffler mounting and connection to pipe loose and faulty by design (entire muffler unsupported; clamped to exhaust pipe)
One cannot change the faulty clamp without disconnecting the exhaust pipe form both cylinders.
No gas filter

The present shop added to this:
Engine inaccessible for repair without tearing entire genset apart.
(Strategic screws buried between engine and generator.)

 

[The Mountain]

Not much consolation, but, get the shop to put it all back together (at least as much as is needed to transport), then take it home, put it out in the garage, go buy a B&S small engine book from Barnes and Noble, and tear the thing down yourself. When I accidentally ran kerosene through my Heald minibike, my dad tore down the engine and cleaned it, and got it running again, and he was no small-engine mechanic. At worst, you can confirm your suspicions about the bad camshaft.


Second alternative: Find some old guy who works out of his garage doing small-engine repairs and barter his services (be a hard-core doomer). After all, if TSHTF, and your generator crapped out, you'd be doing that anyway.

You spent the money on it. Even if it doesn't work, you can still get some benefit out of the thing, and maybe get it running again until you can save the dosh to buy a real commercial engine from Harbor Freight . And on top of that, you'll have a new, marketable skill, and know how to do at least some service on the thing yourself!



You prepped enough to buy a genset, but thought you'd just cart it down to the local small engine shop if it craps out after TSHTF?

 

[WFK]

You prepped enough to buy a genset, but thought you'd just cart it down to the local small engine shop if it craps out after TSHTF?

Booo!

Before Y2k I had considered doomer scenarios that I don't want to repeat now. And one thing was without a shadow of a doubt:
even mild but widespread computer problems would immediately bring the spare parts business for ANYTHING to a halt.

The potential problem was not the willingness to repair but the missing replacement parts that nobody could locate.

So I did have spare oil filters stored for the gen (fortunately they also fit my car..) and spark plugs and gas -with limits.

I have already cried that I didn't subject the genny to an endurance test, which would have shown the fault. So I say: unfair comment!

BTW I HAVE the small engine repair Book, but I am much beyond that. I have more literature for this baby than the repair shop...
(you see, I ordered the parts for which they said only one source existed...)

This genny weighs 300 lbs. Give me a mini bike anytime!

And, after some consultation with my son who comes up with wonderful ideas ("sell the thing on e-Bay") he and I will probably take it apart until we SEE the rings and the camshaft.

 

[WFK]

Correction

Time has expired to correct my post above: re books.

I have ordered online the engine-specific B&S repair manual.
I didn't have that. That opens the possibility for "case" photos some day after I have taken the thing apart.

Two sons say I should WRITE to B&S about my experience and my opinion that I bought a lemon. Does anyone think that such writing would yield any ACTION from B&S, considering that 3 1/2 years have gone by since purchase? (and maybe 20 hrs of actual use.)

 

[The Mountain]

I'd write 'em. After all, a generator isn't necessarily something that would get used often. It might be something that gets bought and put aside for emergency use (Gosh, think of that ). Tell them what happened, and why you bought the gennie (emergency use, not power for a farm or work site). Maybe you'll get nothing, but a letter isn't much effort to make.

 

[WFK]

Progress report:
Generator in basement, dual halogen lamps, digital camera.
Oil drained: black and stinks.
Disassembly has begun. I LOVE the smell of an engine.

 

[richw]

WFK,

Any updates, did you get it apart yet?

 

[WFK]

getting there.
How in the world does the generator come off the engine?

 

[Hamilton Felix]

You may not like this...

I have three of the cheap Generac 5kw units from a few years ago. B&S 10 hp engines. It's my understanding that these engines, built specifically for generator service, have L-O-N-G crankshafts, and the generator rotor goes on the shaft. I'm told the generator doesn't really have bearings; it all depends on the bearing in that side of the engine.

I don't know of this is true of your larger unit. If so, it suggests that the generator stator may have to be removed before the rotor can be accessed to remove it from the crankshaft.

 

[WFK]

HF,
What you say agrees with what the tech said: he would have to pull out the assembly and remove the generator first, and he really didn't want to touch the electrical wiring that had to be diconnected first. He also said that after some use the shafts would seize together and he might not be able to separate them.

*************************

As much as I looked I could not find enough space where a bearing could be on that end of the generator, which would mean there are only three bearings: two for the crankshaft and one for the generator end housing.

So I am in the process of labeling all wiring and then pull it off, followed by the generator end housing, then the armature and then I will know for sure.

At that point I will either be able to pull the generator rotor off the crankshaft or bring all pieces to the dump.

 

[Hamilton Felix]

Good Luck. With my smaller, cheaper units, there may be NO bearing in the generator.

 

[WFK]

Good news:
I have discovered two exploded view generator drawings.
They confirm:
Engine has conical shaft; generator has matching rotor end.
Three bearings total. Shafts held together by 10-in long screw through center of rotor into engine crankshaft.
Still: generator must be taken off in pieces, but now I know how.

 

[richw]

WFK

Glad you found what you need

We were always amazed by generac in the fact that you can pull apart one generator and find a keyed or conical shaft with one bolt holding everything together and the next day pull apart an identical unit made within 6 months of the first and find a conical and keyed shaft that has been pressed together.

I assume those are the ones the mechanic is refuring to.

I have seen more than one that ended up in the scrap heap because the were siezed together.

 

[WFK]

I will lay low here until I pull the piston(s) out.
Unfortunately the shop cleaned the piston top of one piston, so a comparison cannot be documented by photos. But it's got to be visible on the oil ring as well. Weekend coming up.

There is so little wear on the cylinder walls that the original (also specified for rework) crosshatch honing pattern is still visible and almost no up/down wear at all.

 

[WFK]

OK, I am now a the point that the technician dreaded, and so do I.
Well, the long screw in the center of the shaft came loose easily,
but now I am getting to the nitty gritty: How to pull the rotor, or better what to pull it with.

That little problem is all that separates me from taking the piston out.

 

[WFK]

Two 3 1/2 long pipe pieces mounted on red casting, two 6-foot crowbars under rotor laminations and over those pipe pieces. Leverage applied - rotor popped right off. Shaft cone is unkeyed.

First look:
everything looks so new as if just made... there is no wear on cylinder walls.
rings not broken (but are they ground OK? Probably.) But they will be replaced.
(Their gaps did not all point in one direction, that is OK too.)
camshaft pulled: no bumps, no foreign matter. Pressure relief mechanism works OK on both exhaust cams.

Only problem found is a sticky tappet on questionable cylinder exhaust side; I can force it by hand to its seat, and then I am unable to pull it out without tools. This condition exists only on one of four tappets.
That condition goes with the tappet, not the bore.