Splitting an 076

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Boomer 87

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So almost to the splitting point ony 076 crancase, couple questions. Does the oil pump have to be removed assuming out the front? I see the snap ring under it, but it kind of looks like its just there to center the crank in that half. Also anyone able to split one without a special press? Ive got all the bolts out but it doesnt seem to give with some taps from a dead blow on the crank end. Any help would be great.
 
After the oil pump and crank seals are pulled. Get the bar oil out of the tank unless you like fire. Lol
Heat the fan side with a propane torch around the bearing pocket area to around 350º-400º F until the press fit bearing can be easily tapped out, (but first put a steel wedge centered between the crank counterweights to prevent the crank from getting bent.) Put it in there lightly; just enough that it doesn't fall out. Use several nuts stacked on the flywheel threads, or a flywheel knocker nut to prevent thread damage.
Screenshot_20200319-004034.jpg
Hit it straight and solid.
Once it's separated, then use a press for the other side if at all possible. Then use a small bearing separator / puller.
Do the same for reassembly, or the wobble of the bent crank will eat up the bearing pocket if you go hammering on the clutch side..
Good C-3 rated bearings from any auto parts store will work. Just remove the plastic seals and blow out the grease first.
6203-2RS and a 6204-2RS are the two bearing numbers.
 
Be very, very sure you get ALL the case screws out first before tapping it apart.
When you go back together, heat the cases and drop the bearings both in place. Put your wedge back between the center of the crank counter balance weights. Then put three longer all thread m5 bolts in a triangle pattern that are long enough to grab at least four threads at the start. Make sure the hollow alignment dowel pins and case gasket are in place. At this point press the two halves carefully together, or
alternatly screw the three screws in until it's pulled itself tight.
Then put the rest of the screws back in the case.
Next tap the crank increasingly ramping up until the crank spins somewhat freely. Then take out the wedgie. It should spin nice and freely now. If not, rinse and repeat.
 
Only other question, how does the oil pump come out? I assume straight out the front. I put a bolt in the threaded hole in the end of the pump and pulled slightly, it didnt seem to want to move. Wonder if its just stuck on an ORing maybe.
 
After you remove the snap ring on the pump;
It's tapped on the front end with m5 threads.
Thread a bolt in there that's long enough to grab onto with pliers and pull it out. They usually aren't difficult to remove. But, if it is, then you can use a bodywork slide hammer to assist.
Please note that if it wasn't leaking bar oil into the crankcase, and the oiler was functioning good previously, the O-rings and seals are probably good.
It isn't absolutely necessary to pull the pump if it was working prior to teardown. Unless of course you plan to heat the case to remove and install the bearings.
*
Note that if either old bearing slides off the crank by hand, see if the new bearing slides on by hand. If it does, then you will need to replace the crankshaft.
It needs to be press fit.
If the OD of the bearing is loose in the crankcase bearing pocket, you would need to replace the crankcase half AND the crankshaft, as it is more than likely the culprit of the damage.
*
Don't forget to inspect the condition of the seal on the inner part of the drive worm gear on the crankshaft and that the tiny spring is still on the back side of the seal too. . It can be a source of an air leak.
Enjoy...
 
After you remove the snap ring on the pump;
It's tapped on the front end with m5 threads.
Thread a bolt in there that's long enough to grab onto with pliers and pull it out. They usually aren't difficult to remove. But, if it is, then you can use a bodywork slide hammer to assist.
Please note that if it wasn't leaking bar oil into the crankcase, and the oiler was functioning good previously, the O-rings and seals are probably good.
It isn't absolutely necessary to pull the pump if it was working prior to teardown. Unless of course you plan to heat the case to remove and install the bearings.
*
Note that if either old bearing slides off the crank by hand, see if the new bearing slides on by hand. If it does, then you will need to replace the crankshaft.
It needs to be press fit.
If the OD of the bearing is loose in the crankcase bearing pocket, you would need to replace the crankcase half AND the crankshaft, as it is more than likely the culprit of the damage.
*
Don't forget to inspect the condition of the seal on the inner part of the drive worm gear on the crankshaft and that the tiny spring is still on the back side of the seal too. . It can be a source of an air leak.
Enjoy...
After you remove the snap ring on the pump;
It's tapped on the front end with m5 threads.
Thread a bolt in there that's long enough to grab onto with pliers and pull it out. They usually aren't difficult to remove. But, if it is, then you can use a bodywork slide hammer to assist.
Please note that if it wasn't leaking bar oil into the crankcase, and the oiler was functioning good previously, the O-rings and seals are probably good.
It isn't absolutely necessary to pull the pump if it was working prior to teardown. Unless of course you plan to heat the case to remove and install the bearings.
*
Note that if either old bearing slides off the crank by hand, see if the new bearing slides on by hand. If it does, then you will need to replace the crankshaft.
It needs to be press fit.
If the OD of the bearing is loose in the crankcase bearing pocket, you would need to replace the crankcase half AND the crankshaft, as it is more than likely the culprit of the damage.
*
Don't forget to inspect the condition of the seal on the inner part of the drive worm gear on the crankshaft and that the tiny spring is still on the back side of the seal too. . It can be a source of an air leak.
Enjoy...
I appreciate all the help, i got it all apart this morning, everything came apart awesome, nothing overly tight but not loose either. I did not remove the oil pump, im going to try and leave it alone. Just thought it may have to come out to split but wasnt necessary. Now on to the parts washer. Do you suggest pressing the bearings into the cases, then pull together. Or press bearings on the crank the pull together?
 
You're welcome.
Pressing them into the case first is better.
Make sure your lower rod bearing cage doesn't have any cracks in it.
Radial play, (up and down play) in the lower rod bearing should be at zero as well.
Be super careful not to get the rod caught between the halves when pulling it all together.
 
I had two of those 076's at one time. This is the remaining one.
When they would set for a month or two, one would be hydraulic locked because the oil pump assembly had a very small leak. It would fill up the cylinder and crankcase with bar oil.
Once I got the oil out of the spark plug hole, it would start, but smoke like a freight train for 10 minutes or so, then clear up.
Although I never was able to find exactly where it was leaking from, if I stored it for more than a couple weeks, I would lay the saw down with the clutch side up to avoid the problem.
That problem is quite common on these saws, so you probably made the right choice by leaving it alone.
I have a bin full of parts for these 1111 saws if you ever need a source.
The AV rubber mounts are repopped on eBay, and are better and cheaper than the originals.
Post a pic when you get it finished. Cheers, Alex
Here's mine. The chainbrake came new from eBay, they are extremely rare,
and cost me $275.00. downloadfile-57.jpeg0628110912-00.jpgdownloadfile.jpeg
 
Very nice, i saw the repop AV kit which i will be purchasing as mine are pretty soggy. Im glad i never really ran this one since i got it. I heard the bad crank bearings so i shelved it untill i had parts, it was a good thing i had, when i got it apart the intake side piston skirt was broke off but no pieces inside. Almost like someone stuck something under the skirt to lock the engine, broke the piston, removed the pieces and put it back together. Luckily the cylinder is ok.

Cant wait to get it all back together, i have a 56" granberg mill to put it on. I bought an 084 a couple years ago to mill with, but parts are so scarce i didnt use it much. But the aftermarket embraced the 076 and parts are plentiful.
 
Sucess! Was able to split clean and reseal the 076 today. Didnt need to use all thread. I have a shop press like a 20ton but miniature and uses a screw with a T handle so you can feel whats happening. Using thermal dynamics (heat gun and freezer), i was able to press everything together perfectly. Got the cylinder soda blasted and new piston kit with new wrist pin bearing installed.20200322_135336.jpg
 
Well shes all back together, and runs!!!. Sounds healthy, tons of compression. Now just need a new AV kit and a good used flywheel and well be ready to cut
20200324_182011.jpg
 
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