028 oil pump gears

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ftm

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028 oil pump gears problems now w/ pics

I got this used 028WB serial #210810202 saw and am having problems with the oil pump gears mating.
This pic shows the misalignment. Everything is down and seated. I ordered a washer that in the parts diagram looked like it went under the clutch drum in hopes of shimming it out but the washer was pretty thin.
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This shows the parts that were on it in order and the worn gears and cover.

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Here are the replacement parts I have assembled. New cover 1118 021 1102 same as old, oil pump gears same as old 9111 647 0405 and 1119 647 1800, washer 1118 162 8935 that I thought goes under cluth drum, and a washer 0000 958 1021 for under the eclip.

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Finally an oil pump, I read in a thread that there were two used and that it affected everything else.
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Can somebody give me some direction of what I need. The sprocket on it is .325 7t and I guess you call it a 1 piece as opposed to the two piece and the rimless setup. If I were keeping this saw I would go rimless and change the size to 3/8 but I plan on selling it so I don't want to throw any modification money at it.
 
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NO pictures. Just attach them if you're having trouble inserting them as images.

I'm sure I can help, but I'll need the first pic at least.
 
I'm not seeing anything obvious. Are you talkiing about the vertical displacement in picture 1? Do they mesh properly when you rotate them?
 
No, they are always a little less than half a tooth width off. Either the oil pump is too high(with it on its side as pictured) or the clutch drum is too low right? Can I put a bigger shim/washer between drum and clutch? Between the drum and plastic gear?
 
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Hmm, this is a lot harder when you can't see the actual saw!

Don't add in anything that wasn't supposed to be there originally. It is all designed to work..

Have you tried running it? if the cover goes on over the pump etc, without forcing it, I probably wouldn't worry about it.
 
Yeah that is a problem. I put it back together just like it came apart but since the original gears were all ate up I am supposing the same thing would happen. The parts list show parts for earler models and don't make sense. I am trying to figure out what the correct way is.
 
My father had an O29 super that striped an oil gear on the first job. He had it replaced, and it striped the new one too. Then the shop said he needed a washer to shim it out. He striped another oil gear. Then they said the worm gear was bad, so to make a long story short, two worm gears later the crank bearing burned up. Needless to say, we don't use that shop anymore, but I couldn't let it go so I asked our new shop guy about it and he said the oil pump itself was bad and should have been replaced. I dunno if any of that helps you, except that I recommend doing your homework or talking to somebody who KNOWS FOR DARN SURE before you burn up your saw.
 
BDawson1234 said:
My father had an O29 super that striped an oil gear on the first job. He had it replaced, and it striped the new one too. Then the shop said he needed a washer to shim it out. He striped another oil gear. Then they said the worm gear was bad, so to make a long story short, two worm gears later the crank bearing burned up. Needless to say, we don't use that shop anymore, but I couldn't let it go so I asked our new shop guy about it and he said the oil pump itself was bad and should have been replaced. I dunno if any of that helps you, except that I recommend doing your homework or talking to somebody who KNOWS FOR DARN SURE before you burn up your saw.


The 029 is completely different to the 028... and no confusion as to the correct parts.
 
Which tends to be my luck. I guess I will drag it to a couple shops and hopefully find someone that is familiar with them.
 
There's only two different setups, and any shop that deals with them will recognize the issue. If you were here, it would only take a few minutes to figure out, but...

If you turn the clutch drum clockwise and the oil pump spins freely (you may have to hold slight pressure down on the pump gear - which is what the side cover does), it will all work. I don't remember the exact issue but the "wrong" combination of parts just doesn't work at all.

I have a couple of 028WB in for service right now. I'll get to them early next week and I'll be able to see whether the gears mesh like yours or not.
 
I look forward to your tearing into them. I keep looking at mine and trying to figure out what could be wrong. One thought is the oil pump itself. The part number on it does not match up to anything in the two different ipl's I have. Could it be from another saw and a little bit wider? The difference in my gears meshing fully is about 1.7mm. The gears themselves are 4.2mm.
 
It's possible.. but the number of the pump is NOT the part number of the pump... it's a body casting part number. The very best thing to do is take it to to a dealer that knows older saws, show them and have them try the two different sets of gears etc until you find one that fits, or, if it's for sure you have the right gears, try another oil pump. There are usually a lot of old pumps lying in boxes... I know we have some.

I checked a couple of 028 oil drive systems yesterday, and they both meshed "flat".
 
Not good

here's what they SHOULD NOT look like ;)


Note the "blue" clutch drum. (sap - quick, what temperature does this happen at?)


Saw came in for a "minor tune", and, btw, "check the oiler". It will live to saw another day.

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On a side note ftm... that spur sprocket is completely worn out. It has some serious grooves worn in it from the chain. It's been on there a while. Just an observation.

Gary
 
Gasoline, are you talking about the one piece chain sprocket/clutch drum? Where the chain rides? I don't understand what you mean. I looked at the area where the chain rides and didn't see any abnormal wear.

On the oil pump side of the post I went to two dealers today. I don't believe either one of them was very familiar with that model. They both said they it was ok for the gears to not line up completely. That they didn't have to have full contact. One of them mentioned that the clutch drum with spur gear would float out a little bit on the crankshaft after the bar was mounted. I see that would help a bit.
 
yup, that's exactly what I'm referrin' to. When they are new there are no groves in them at all. Nice and smooth. When they wear out the grooves match where the chain has been riding on them for years. When a lot of people get an older saw they assume that the grooves in the sprocket are supposed to be there because they match the chain perfectly.

They aren't expensive to replace, and will help the chain "float" a little better on the sprocket. I belive you can convert it to a "rim" sprocket. My 028WB came with a rim sprocket, so I'm sure it can be converted.

This is where my expertise (what little I have), runs out. Andy (Lakeside53) is the man on this stuff. Andy???:bowdown:

Gary
 
Hey guys. I wanted to report back on this. I used the saw several weeks ago but haven't had a chance to take it apart and look at the parts until now. I don't see any wear which is good. It seems that the odd gear contact fixes itself once you get the chain on as the whole clutch drum will float out a little and thus give the gears a better contact area.
 

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