Wild Idea

Some time ago I managed to tip my compressor over , landed on the pulley .
The pulley survived , but the connecting rods didn't . Snapped 'em both off
just above the big end . Fast forward to now , and the replacement pump I
bought is blowing oil ... from excessive blowby . I haven't pulled it down
yet , but the rings have gotta be shot or broken of just plain crap to begin
with .
And this is where the wild idea comes in . The rods in the cheap pump
might fit , or they might not ... and if they don't I'm thinking about TIG
welding the broken ones back together . I can build a fixture to hold the
two bearings in alignment . I'd be most worried about the temper of the
repaired area , but a quick chill and a few days aging might get it back
enough .
Is this a waste of time , or do I stand a decent chance of having this
work ?
Reply to
Snag's Shop
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Don't know about the rods... there's probably a lot of variables...
However, before going to all the trouble, are you sure the crankshaft is still straight? How about the crankcase and 'main' bearing's?
Erik
Reply to
Erik
Probably a wasto of time. Kind of depends on how good the compressor was b efore the acident. If it is a good compressor then replacement parts are a vailablo. So you could try the repair and if it does not work , then order replacement parts. But probably makes more sense to look at Craigslist fo r a new to you compressor.
If the motor and tank are good, you can buy a replacement pump.
Dan
Reply to
dcaster
In this Obama depression, I can magine people selling off tools, at sacrifice prices. I'd think the OP should check the Craigslist and other ads. Might score a good unit, at a low price.
. Christopher A. Young Learn about Jesus
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Reply to
Stormin Mormon
Northern Hydraulic, and Harbor Freight both have replacement compressor, without having to buy the motor, tank, etc.
Maybe some oil additive, to reduce blowby? Don't know if Marvels Mystery Oil would do any good in a compressor crankcase.
. Christopher A. Young Learn about Jesus
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Reply to
Stormin Mormon
My ignorant guess, is that any repair to a piston rod is going to fail at the worst possible moment. Some things just can't be repaired, and get it right. Suppose you weld, and the weight throws the balance off, and now you've got a wicked vibration.
you don't mention if this is belt or direct drive, and how many amps, HP, and so on. My thought is to look for a cheap replacement, Ebay or Craigs list. Or, buy the pump from Northern Tools, or Harbor Freight.
I like the concept of repairing things, but this isn't one of those moments.
. Christopher A. Young Learn about Jesus
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Reply to
Stormin Mormon
When it landed it pushed the crank bearings out the other side . Crank still spins easily , and it looks like the bearings just need to be pushed the rest of the way back in place . There is no or very little axial load , just the radial loads . -- Snag and it is/was a good I-R pump
Reply to
Snag
If it is an IR you should be able to buy rods. They are aluminum or sintered iron???. If Iron I'd be awfull tempted to braze them. If aluminum, tig them. Weigh them first on an accurate scale and grind to match after welding/brazing. It's worth a try. They are not under nEAR the load they would be on an engine.
Or see if any Brigs and Stratton or Tecumseh or whatever rod can be modified to fit.
Reply to
clare
All this talk of repairing con-rods is silly. Make new ones, if you must.
BUT! My real question is this: What sort of situation would have someone tipping over and allowing to fall a compressor WHILE IT WAS FRIGGIN' RUNNING?
There is no way that could have damaged the con-rods if it were off. So... What the HELL did you do? (And maybe WHY would be a good one, too.)
LLoyd
Reply to
Lloyd E. Sponenburgh
What, a little plumber's tape and Chiwanese screws won't last?
Simple. The wide receiver didn't see it in his way as he ran for the touchdown in Snag's shop. Either that or the QB tossed the beer too high and the receiver didn't see the comp.
I'd like to know how they were damaged, too. You shouldn't see that unless he snapped the head off the sump and the little legs done bended too much. But the crank would be the most likely piece to break, not either of the rods, and certainly not both. Pistons are lightweight.
Reply to
Larry Jaques
Actually , I was backing a load of lumber in and the end of a 2x4 12 feet long pushed it over . I was watching the other side to be sure I didn't back into one of the legs of the carport that's now my shop space . Compressor wasn't running , wasn't even hooked up . It landed on the pulley , pushed the crank bearings out and snapped both rods . eBay has 'em for 22 bucks each , and I shoulda repaired it then ... The point has been rendered moot . I tore the new unit down , discovered that the top 2 rings on both pistons appear to have been installed upside down . Bottom edge of both was shiny , top edge has never touched the cylinder wall . No wonder there was blowby ! So I did a light hone on both cylinders and turned the rings over , seems to have solved the problem . But next trip to Memphis I'm bringing the other pump up for parts to repair the one with busted rods . -- Snag out in the shop
Reply to
Snag's Shop
"Snag's Shop" fired this volley in news:l15bhe$a8b$ snipped-for-privacy@dont-email.me:
Amazing. I cannot even conceive of moving that far, that hard, against something I could _feel_and_hear_ when I hit it -- even in a large pickup truck.
Oh, well. If the con-rods are only $22 each, it can't be much of compressor pump, anyway.
Lloyd
Reply to
Lloyd E. Sponenburgh
Ya know Lloyd I used to have respect for you . You weren't there , don't know the situation or even what the compressor looks like . And yet you feel you need to judge me - and to judge my equipment to boot ! Everyone isn't flush enough to buy the very best of everything . I consider myself lucky to have what I do , whether top-of-the-line or barely adequate . -- Snag
Reply to
Snag
"Snag" fired this volley in news:l15l1p$kdi$1@dont- email.me:
I did NOT judge you. I said ____I____ could not imagine doing that.
I know of a lot of folks who could (both imagine AND do it).
I don't judge them, either.
But I wasn't 'judging' about con-rods. If they're that cheap, they're "cheap". It's not a matter of what you can or can't afford. That's a statement about the quality of the unit.
I've often been in situations where I couldn't afford the 'best'. But I recognized the stuff I could afford as being whatever quality it was.
I never got mad at someone else who did, too.
Lloyd
Reply to
Lloyd E. Sponenburgh
Sometimes things (parts) are sold at a decent price - sometmes at overinflated prices. What is a simple low-stress connecting rod REA:LLY worth???? Briggs, Tecumseh and Kohler run $15 to $90 online. These are for an ENGINE that runs 3600 RPM. The compressor runs closer to 600 RPM and experiences significantly less compressive stress as well as a lot less stretch.
Reply to
clare
snipped-for-privacy@snyder.on.ca fired this volley in news: snipped-for-privacy@4ax.com:
They're also for engines that are made in the tens of millions per year to be 'throwaway' devices, and for which they need to supply parts to make their market buy the engines.
Good compressor pumps sell in the tens of thousands per year.
You figure the economies of scale.
Lloyd
Reply to
Lloyd E. Sponenburgh
"Lloyd E. Sponenburgh" fired this volley in news:XnsA23CDA2C2EA98lloydspmindspringcom@216.168.3.70:
You also might compare the prices.
I can buy a name-brand 5HP engine all-up for $150 bucks on sale. Good quality industrial quality air pumps sell for eight times that; usually no sales.
Lloyd
Reply to
Lloyd E. Sponenburgh

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