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Discussion Starter #1
Hey All,

Appologies for the rambling...

I haven't got much experience fixing engines but i got ahold of a freebie from my buddy recently and i'm trying to get it going. No luck so far. Throughout all the efforts below, almost the exact same symptom: Pull on the starter cord and it won't start... doesn't even come close. The gas is maybe 4+ months old, but my mower is running on the same stuff and i believe i put stabalizer in the can after i filled up at the gas station.

It's a Sears powerwasher with a Briggs and Stratton... i'll have to look for a model number when i get home. Only specs i have on hand are:

Bore 2.69in, Stroke 2.04in, Displacement 11.57in3/190cc

I think the iniitial problem was that he cross-threaded the spark plug during a tune-up. He used a thread-saver but didn't remove the head, so all the tapping shavings ended up in the cylinder. I'm unclear how much time he spent trying to start it after the shavings were floating around in there. Sears quoted him a ton of money to fix it so he just bought a new one.

I took the head off and cleaned the shavings out with compressed air. I was expecting to see a huge mess with scratches and nastiness along the cylinder but it looked "good to me"... which means nothing since i'm not experience. But still wouldn't start after cleanout and re-assembly.

Next i noticed that the spark plug wouldn't tighten all the way down. I took out the plug and the saver-threads came out with it. So i re-tapped the threads with a new saver kit... i don't think the first saver-thread-sleeve was inserted deep enough. Reassemble, plug looks snug, still won't start.

For kicks i check the model number on the plug - it's an autolite (i think?) but i can't find anything online to indicate that it's compatible with the recommended plug for the engine (which is B&S 491055S). So i grab a suitable Champion replacement plug at HD. Sadly, taking out the old plug now rips out *my* thread-saver. Tapping a 3rd time didn't go smoothly - hole was too large for 3rd saver-sleeve. Last resort, i coated a sleeve with JB Weld and put it in. Next day - pretty good result. Seems solid. Pop in the new Champion plug, seems snug... still nothing.

I was considering buying a cheap compression tester from Harbor Freight but read some scarry reviews that said they are garbage. I cannot invest too much more money into this project ... diminishing returns and all. This thing might end up in the junk pile shortly. Hope you guys can recommend something.

Other info:

I thought i saw some smoke puffs coming out the intake when i was trying to start it. I read this is a symptom of over-filled oil. Indeed... my oil level was high, so i emptied some. Still feel like i see a little bit of a puff out of the intake, but it was getting dark when i was testing last and i was punchy by then. If puffs are coming out the intake, is this engine done?

I took apart the block to see if shaving made it past the piston (and, i admit, also because i was curious what it looked like in there). Didn't see any shavings or obvious damage. When re-assembling, i wasn't quite sure how close the magneto is supposed to go to the flywheel. There is maybe 1/8" (or less) play when mounting it. Currently i have it 'far' from the flywheel because i didn't want to risk rubbing, but that was guesswork. Should it be 'close as possible'? I tried measuring the voltage generated by the magneto with a volt meter but couldn't get meaningful measurements and have no idea what they're supposed to be anyhow. Grasping at straws at this point.

The paper gasket got pretty much wrecked when i openned the block. I hadn't thought about that before opening it. When reassembling i used some copper-high-temp gasket paste (silicon something?) to try to augment the sloppy gasket. I just wanted it to hold well enough so i could see if the engine would run.. then i could get a new gasket and fix it right. Would there be so much leakage due to that gasket mess that i wouldn't even get it to start at all?

The push rods fit very tight against the rocker arms (or whatever they're called). I thought there was supposed to be some gap.. but i'm pretty sure they were like that before i did any messing around.

Anyway... if i'm overlooking something very simple that i should try, i'd appreciate any feedback. Also curious what the cheapest (yet still effective) compression tester is...

Thanks a lot,
Joe
 

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Hello and Welcome to Hobby Talk Joe.I have included a link to the service manual for your motor.I think you have a 120000 OHV series engine?You will definitely have to replace the cylinder head some where in the future,but for now,just get it running.
Page 21 of the manual has the adjustment procedure for setting the valves.Pay attention to the rotation of the crank shaft and the 1/4" past top dead center.The intake clearance is .004-.006,the exhaust is .010-.014.It sounds like your valves may be way out of adjustment and is probably affecting the compression.Most if not all small engines have an automatic compression release to make starting easier and is dependent on the valve clearances being set to specs.
The air gap between the fly wheel and the coil is .010-.014 and most people use a new business card as a feeler gauge.Just loosen the coil,put the card on top of the fly wheel magnets and push the coil down and tighten the screws,then remove the card.This should be enough info to get you started.Hope this helps.

http://dl.dropbox.com/u/12502267/B&S Service Manuals/10_276781SingleCylinderOHV.pdf

It would also be in your best interest to dump the old gas and refill with fresh fuel.
 

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Discussion Starter #3
Thanks a lot usmcgrunt. Appreciate the link to the pdf. Took a quick look at it last night and read a bit about valve adjustment. None of the images would load, but maybe that's because i was browsing on a phone? Dropbox is blocked from my job, so i can't check it now. It looked helpful even without the pics though.

No time to play with the engine last night, but when heading out to work this morning i looked around and found "875 Series" on the plastic engine cover. And a there's a line in the manual that says "Model 120000 engines are certified by the Califoria Air Resources Board....", so it looks like you were dead on.

I like the business card trick. Good stuff.

Thanks again,
Joe
 

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Discussion Starter #5
It lives!

But just barely. Moved the magneto and tried to adjust the valves. First attempt was no good. I think my 1/4" past TDC was rotating in the wrong direction. Second time I got it running. I still think it must be off because part of the stroke when trying to start it pretty much stops the pull dead and I think there was a backfire when it started up.

I ran it a couple minutes then shut it down. I notices some smoke or steam coming up from through the flywheel / starter pull area after shutdown. Didn't have time to try to diagnose it. Pretty much all my gaskets are a mess so could be some sort of leak from anywhere I guess.

Still some work to do but I'm a lot better off than I was a few days ago. Thanks
 

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Glad to hear Frankenstein lives!!! It sounds like the valves may still be a little off and the compression release built into the cam shaft isn't doing it's job in lowering compression during start.Recheck the clearances on the valves according to the manual,it is critical to a good running motor.Are you sure you don't have the coil rubbing on the fly wheel? That would cause hard starting and smoke from the recoil area.Have you checked the oil level? to high is just as bad as to little.Let us know how you progress and some one here will be glad to help.Good job so far.

The stripped spark plug hole may come back to haunt you later.If the valves are set correctly and it is still hard to start or back fires,the key that aligns the fly wheel to the crank shaft may be partially sheared.
 

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Discussion Starter #7
I picked up some nozzles this weekend and tried out the power washer.

Little bit of a pain to start but It ran fairly well. Leaked a little oil onto the front of the frame. I think the valve cover gasket might be shot.

Cleaned a few things. Worked well. Maybe 20 minutes of continuous use. Unfortunately, at that point usmcgrunt's prediction came through. The spark plug shot out of the head and across my patio. Seems my PB Weld didn't hold as a fix to the stripped threads.

I'm a little bummed because Including a set of nozzles i'm into this project close to $100 and i could probably have bought a new washer for 200-300. Ideally i need a new head, but i'm not sure where to look for one or how much to expect to pay. also need some gaskets but don't know where best to buy

I may give it another shot with the PB Weld but it seems that's not a good long term solution.

Secondary issue. The spark plug had a little white stuff on it. I did some research and see it can be due to a couple of things:
1) running 'hot' - is that referring to the plug itself not being correct for the application? i'm pretty sure it's the right plug.

2) timing being off. this wouldn't surprise me since i've torn this thing completely down and put it back together with just about zero experience beforehand. i was talking to a buddy and he asked if i was careful when putting the cam shaft back in to make sure the gearing was correct. i'm typically pretty careful with details but i can't remember what i did. i'll have to review the manual to see how to ensure it's aligned right - i feel like there was only one way to put it back in but my buddy said there might have been dots on the gears that needed to be aligned.... i cannot for the life of me remember what it looked like.

if the timing is off, could that increase temperature and pressure in the cylinder and prematurely kill my PB Weld? i've read that it is supposed to hold up in sparkplug repairs like that and i'm wondering if i fix a timing problem if another shot with that epoxy stuff might have a better chance.

thanks,
joe
 

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If you have an automotive machine shop nearby you might take your head and plug by and get an estimate.They may have something better than a helicoil.A small engine shop may even have a used head but that's a long shot.
For ordering parts I've been very pleased with Jack's Small Engine.
Best of luck,Don
 

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Discussion Starter #9
Thanks Don - i checked out Jack's Small Engine. Looks like a good resource.

There's a auto-transmission shop right near me. Not sure if there's any engine shops nearby but i'll have a look around.

I was reading the manual and there are 2 dots on the crank and cam gearing to align. I'd be surprised if i ignored them during my reassembly but i honestly can't remember. So frustrating because i dont really feel like tearing it all down again.
 

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Discussion Starter #10
rather than correct my 50 mistakes in previous posts i will appolgize here... i continually misname JB Weld as PB Weld. sandwiches on the brain, etc...
 

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You can check Yellow Pages for"Auto Machine Shops".
I did'nt catch the typos.One time I showed one of my paint jobs to a pro and he said"Do you know the difference between a professional and an amatuer?".I said "no" and he said"A professional dose'nt point out his mistakes."
Down here in the south we have slightly different phrase for sandwiches on the brain.:wave:
 

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Discussion Starter #12
that's a great saying... but if i didn't point out my mistakes i'd have nothing to talk about :p

i tore everything apart (for the 3rd time) yesterday. the cam gear and crank gear markings were not aligned... no idea how the engine was running at all. lined them up, sealed up the block with more high temp silicone (still haven't picked up new gaskets) and reassembled. this might explain why there was a point in the pull-cycle where the rope would stop dead. who knows how the valves were operating well enough to run the motor. i readjusted the valve clearances (or whatever that's called) afterwards.

too cheap and lazy to look for a shop right now. i cleaned out the existing hole in the head with a sire brush on a dremmel. then i reinstalled the helicoil for the spark plug with some JB Weld again.

one of my buddies recommeneded getting a spark plug with larger threads (think he said Ford uses M18 instead of M14 plugs?) and drilling out the hole and retapping. trick would be to find a plug with wider threads that fits my application. and i'm not certain if the head even has +2mm available all around the exisitng hole without hitting something internally.

i let the silicone gasket paste dry overnight and fired the sucker up this morning. MUCH easier to start. 2nd pull. ran alright. not as smooth as i'd like, but i'll take anything at this point. just looking to have a power washer i can use from time to time for small jobs.

did a little more work cleaning my deck and it was OK. maybe 20 minutes of use but i didn't run it wot continuous... gave it a break every couple mins. if i have to go easy on it to get some use out of it, that's fine with me. just have to remember to point the head in a safe direction so i don't send a spark plug through a window if the threads give way again. that would suck.

thanks for the advice and encouragement.
joe
 

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That's great news Joe.Another word of caution tho.Now that winter and freezing temps are coming,store the power washer in a warm area or get some pump saver anti freeze in the pump.Otherwise,next spring,you'll be looking for a pump to replace this one that cracked from the freezing water inside it.
 

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Discussion Starter #14
hmmm.. i thought i replied to this thread before but i don't see my last post?

thanks for the info about winterizing the pump usmcgrunt. i never would have thought of that.

things have been a mess near me (north NJ) for the last ~2 weeks since Sandy hit. more chainsaw work than power washer work for me :p

yesterday i tried the power washer to clean off some logs i'm thinking of cutting into boards. things are not looking good. it would not operate the pump at all until it warmed up for a couple minutes. then it ran well for 10 minutes, but eventually popped the plug out again when the JB Weld failed.

i was wondering if "alumaloy" might work. can i partially fill the spark plug hole with this stuff then retap new threads? i read some people say alumaloy is not so useful for structural repairs - only cosmetic stuff... but i think that is contrary to the advertised use of the stuff?

http://www.alumaloy.net/

any comments on why the engine would need to warm up for so long before operating strong enough to run the pump? it was probably in the low 50's outside. does that indicate low compression at cold operation? i'm thinking i might have to toss this project after all :(
 

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You folks really got hammered with Sandy and the Nor'Easter!!!
I would not waste the time trying to fill the hole and rethread it. Especially being it is the spark plug hole. Those threads are subject to alot of stress and will not last. Usually a thread locker like locktite is used for a Helicoil repair. If you plan on continuing this project, I would consider a used head rather than trying to repair the bad one.
At 50 degrees the engine oil is a little stiff due to the lower temp. The engine workes a little harder until the oil warms up. Also if the pump has oil in it, it is also a bit stiff and needs to warm up.
 

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Joe,
I agree with USMCgrunt that you should check your Valve clearances and stay away from the JB Weld for the plug. Get a set of feeler gauges and adjust your valves then see about getting a new head.
 

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Discussion Starter #17
I did a little searching but haven't found a used head yet. I think i saw that new ones go for something close to $100? That sounds crazy to me.

The Predator engines from Harbor Freight are just over $100 for 5.5hp when on sale if i remember right. I thought i read they were Subaru designes? Anyone give them thumbs up/down?

Not sure i could find one to fit my exact application. But I was also thinking about getting one of the Predator power generators - i've read mostly good reviews of them so far but nobody has commented on the long term reliability of those engines.
 

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For the record, i gave the Alumaloy method a shot this weekend. No luck. In case anyone else stumbles across this thread and is interested:

1) I was using the Harbor Freight Alumaloy-like product to see if this fix approach was possible. It was easier to pick up than order online and wait. Both melt near 720degs i think and i read a properly working engine shoul only get into the 500's when operating? No idea if that's true but i gave it a try anyway

2) I read that repairing thick metal with this stuff is difficult because the bulk of the item acts as a heatsink and sucks the heat away from the working surface.

3) I read that propane torch is generally not hot enought to work with this stuff

4) I read that unless the surface is very clean, the produce will not stick to it well.


Well... for thin metal, the propane torch worked fine. I recreated the "fix a hole in the bottom of an aluminum can" demonstration with no problem. Unfortunately, that was the end of the good news....

I saw examples of thread repair where you leave a bolt in the over-sized / stripped hole and then melt the alumaloy product around the bolt. Then you unscrew the bolt and you have perfect threads. This did not seem an option in this case because of how the head is shaped... once a plug is in the hole there's no room to work. Alternatively, i've seen people partially fill the hole with product and then re-tap.... that was the approach i had to try.

Issues 2, 3 and 4 were definitely problems When heating the area of the threads, the entire head got hot and i couldn't keep the working surface hot enough to consistenly melt the aluminum rod. The few times i got it hot enough (just for a second) the rod would melt but not stick to the head, and just drip out onto the floor. I tried cleaning the thread area with a stiff wire brush (a battery brush actually) but i could see i didn't quite get it completely clean from the JB Weld i had used before.

I was hoping i could get some of the product in place to give this repair technique a shot and see how it held up to the heat inside the head. But no go. Maybe with a hotter torch it could be possible to melt the stuff easier and get some of it to stick (i've heard MAPP? is the way to go?).

My efforts on this project are exhausted. I may look around for a cheap used head, but more likely i'm going to toss this headache in the trash. I fear there may be other issues besides the plug threads and i feel pretty defeated at this point. With all the time i've put into this i could have worked a part time job for a while and then bought a new power washer by now :tongue:


Not a total loss though. I learned a lot. Thanks to everyone who gave me advice and encouragement.

Take care,
Joe
 

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Joe,that was a great review on the alumaloy product,thank you! I was hoping your next post would have some good news,since you were so determined to make it work.A Helicoil might/could/should work,but also a gamble and added expense.Even though you are abandoning the project,don't forget to store the pump in a warm space for possible future use or sale. :thumbsup::thumbsup:For having the determination to continue.
 

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Joe,that was a great review on the alumaloy product,thank you! I was hoping your next post would have some good news,since you were so determined to make it work.A Helicoil might/could/should work,but also a gamble and added expense.Even though you are abandoning the project,don't forget to store the pump in a warm space for possible future use or sale. :thumbsup::thumbsup:For having the determination to continue.
Thanks! I was really hoping to get this thing restored but i've got too many other projects to put any more time or money into this. Hopefully i'll prevent someone from going to Harbor Freight and wasting $40 on a propane torch and aluminum rod to try this repair technique. If someone has a hotter torch handy and gives that a shot i hope they post their results.

Take Care,
Joe
 
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