Counter balance issue

[weatherjack]

I bought a 1996 Blaster with the hopes of being able to ride it some day. The previous owner stated that it did not run. He had owned the Blaster since new and had not used it in a long time. I am learning about two strokes for the first time. I started the motor after checking things over. It was making a clanking sound that I did not like and immediately shut it off. I ran it for maybe five seconds. I did a leak down test and the results, well lets just say it would not hold any pressure what so ever. I have pulled the motor and opened it up to have a look. Over all thngs looked good. Then I checked the counter balance gear and it wobbled. I knew something was bad. It looks like it ate up the bearing and was decomissioned becuase of this problem. I did not see and metal shavings or flakes (have not split case). I feel the previous owner rebuilt the motor unaware of this issue and stopped riding it because of the noise. So my question is at this point do I stop and scrap the Blaster or can this be fixed without buying a new case?

 

[jbuckster07]

Def dont scrapit!!! Switching out a case really isnt that hard!!

 

[weatherjack]

I am going to work some on it tonight. I will split the case and see how it looks from the other side. Is this common for this bearing to eat itself?

 

[weatherjack]

Splitting the case is not hard was an understatement. I gave it a light tap around the case with a 16 OZ rubber mallet and the case opened right up. Good news to report the counter balance is in good shape and the bearing still has the outer ring. So no damage to the case exept the small chip seen in the photo. I dont think I will be able to reuse that bearing. I did find the rest of the bearing inside. Now I have to study disasembly of the inside so I can clean it out and inspect for damage. What is a safe way to clean all of the gunk out? Brake cleaner?

 

[OConnor Racing]

Brake cleaner will clean everything up nice. Be sure to replace both counter balance shaft bearings. It's a good idea to replace the main bearings and all of the engine seals while you're in there. Use an OEM base gasket and replace the lock washers for the clutch and counter balance shaft.

 

[weatherjack]

Yeah the bearings and seals are a must. I dont like the idea that not doing these could result in the same reason I am doing this now.

 

[Larry's Shee]

X-2 on what Ken said. I had a similar situation and it trashed the cases. Don't know if the bearing failed taking out the gear, or gear failed first.
The gear would have a little slop because there's 3 rubber cushions in it. If you think there is to much slop, just replace it with new. @ $70. It spins at same speed as crank is why good idea to replace all. Left case will need blind bearing puller. You could heat case in oven @ 170 / warm and it, and the other bearings should fall out. Make sure bearing for counter shaft is seated properly if it happens to fall out or move.

My problem was the "MOD" bug bit me and I threw a 3mil in while it was split

Heat and freeze works good for installation. NEVER use a torch on the casesor bearings.
Inspect for damage between balancer area and crank area.

 

[weatherjack]

Here is where I am at. I cleaned the cases and all internals (not a final clean just for inspection right now). Hoping to get a feel from others with more knowlege on these than myself if the case is too damaged to use before I proceed. If the consensus is yup go ahead and continue then I will be getting my next round of tools (seal puller, blind puller (Thanks Larry's), crank puller/installer followed by all new bearings and seals. Recommendations on a kit that includes everything needed would be welcomed and appreciated greatly. Then I will proceed with internals and gaskets. So we all love pictures right?

Thanks for the info guys.

 

[Larry's Shee]

Looks good to me. I would hit any place it rubbed with Emery cloth or sand paper to remove any little bits that might flake off later.
That one picis normal machining. I would check the side clearance of the rod and side to side of the small end. The specs are in the manual.

I use this : https://www.harborfreight.com/bolt-type-wheel-puller-set-62620.html to split cases and pull cranks. It has right length and thread bolts for it. Seems all engines are different as to splitting and assembly. Bearings stay in case or come out with crank. It's all a matter of tolerances.

Might as well have the cylinder measured for tolerances, out of round, taper, piston clearance. Blasters have a nasty habit of breaking pistons when they get sloppy. Chunks get caught between case and crank and cause all kinds of damage .

Any reason you removed rings from piston? No matter,markings on rings face up.

 

[weatherjack]

Looks good to me. I would hit any place it rubbed with Emery cloth or sand paper to remove any little bits that might flake off later.
That one picis normal machining. I would check the side clearance of the rod and side to side of the small end. The specs are in the manual.

I use this : https://www.harborfreight.com/bolt-type-wheel-puller-set-62620.html to split cases and pull cranks. It has right length and thread bolts for it. Seems all engines are different as to splitting and assembly. Bearings stay in case or come out with crank. It's all a matter of tolerances.

Might as well have the cylinder measured for tolerances, out of round, taper, piston clearance. Blasters have a nasty habit of breaking pistons when they get sloppy. Chunks get caught between case and crank and cause all kinds of damage .

Any reason you removed rings from piston? No matter,markings on rings face up.

Thanks again for the information. I will check (or have checked) tolerances. I also owe you one for the puller set idea. I was on the fence about it at first but decided to try it. It worked great. I just took my time and the crank came right out. While I was at HF I also picked up the seal puller. Total cost was 21$ with a coupon and saved me 65$ compared to the puller and seal tool I had planned on purchasing. I BBQ'd the cases after removing the crank and seals. At 230 °F I removed them and used sockets with a rubber mallet to tap them out (wife was less than impressed but hey at least I was not using the oven). I still have to get a blind hole puller for the others. I purchased an engine kit from RMATV yesterday.... Yesterday and was on my porch this morning (Amazon needs to learn something from these folks). I removed the rings becuase well no reason really I have never do so and wanted to get a feel for it. So I guess now it would be good to relocate over to rebuilds? Anyway it is picture time!

 

[Larry's Shee]

A+++
​

On crank replacement !!

 

[Larry's Shee]

Your get to a point where you either have to part it out, or totally rebuild it. That's what I did. Took a year to find cases for a deal, then new balancer brgs. $50. It was already apart, got the crank at dealers cost because I know Paul @ Vito's, relatively fresh bore and wiseco piston. Then I had a nearly 100% rebuilt engine.

At this point I'd suggest new bore and piston.

Females are funny, there's something about engine parts in the kitchen, especially the oven that just sets them off

The peace of mind of having most major pieces 100% is priceless. Think of it this way, it took 22years to get to this point, it should last about 20 more.

 

[weatherjack]

I have the bearings in. Used the BBQ again. I received two crank seals and unsure on which one goes to what side? I am thinking the black seal goes to left side case? Also what is every ones thought on this clutch basket? Toss it?

 

[Larry's Shee]

The seal with only one lip goes on stator side. I also think they are different sizes. The collar on right side should fit only one. The numbers on that seal will face you when installed.
Pics no work for me. Presume there is grooving on the fingers.
You can carefully file it if not to bad .

Pics work now

First thread I found https://www.blasterforum.com/threads/outer-Uclutch-basket.66829/#post-808538
I would say it and yours aren't that bad, still salvagabsal. However, that small gear is a problem.

https://www.google.com/search?q=how...oid-sprint-us&sourceid=chrome-mobile&ie=UTF-8

 

[Blaner]

Looking good, keeping an eye on this. Nice to see the caution and careful assessment of parts!

 

[weatherjack]

Still a little confused on the seals? Which one goes on the magneto side and which one goes on the clutch side? Then this vague installation step: (4-32 Page 102) • Apply the lithium soap base grease to the oil seal lips (what lips? inside? outside?). Is CRC 05037 ok to use for this? [Not to start a debate but this is a statement on the same page • Fit the left crankcase onto the right case. Tap lightly on the case with a soft hammer.] And the big question today will be. How do you apply your yamabond 4 (that is what you use right?)? I am thinking it should be applied like the adhesive on a band aid. Thoughts and questions welcomed.

 

[Larry's Shee]

Very good question about the Yamabond. I use what's known as a plumber's acid brush https://www.google.com/search?q=Plu...oid-sprint-us&sourceid=chrome-mobile&ie=UTF-8 can also buy individually at cheapo Depot.
I use Threebond, same stuff, little cheaper.
DO NOT use silicone of any type.

 

[weatherjack]

Thanks Larry. I have all the parts in and going to attempt to complete the bottom. I have run into an issue or maybe not. Is this normal? The plate on top has play in it. Tried to upload a .gif or webp but failed.

 

[Larry's Shee]

The gear has three main pieces, with gearsandwiched between. There are three little rubber bushings in there. In center pic I don't like the top rivet, looks loose. If I remember, I'll see if I have a gear laying around to compare.
That gear is kinda pricey, $70-80.

 

[weatherjack]

Yeah If it has rubber bushings mine has none. You are correct on it being loose. I tried to up load a gif and other formats to show the plate moving but BF would not let me. I kept getting security errors. The part number is 37F-11530-00-00 It states Balancer weight gear comp. (not sure if comp. means complete and this was something you could buy buy parts for?). Anyway I could not locate any specs for this and I am going to replace it. I also have to order another clip I missed so I will be ordering all new washers as well.