Hi everyone I’ve been trying to get this 95 blaster running, when I got it the piston skirt had exploded so I spent a good bit of time getting all the metal out by flushing it with 2 stroke oil I know probably really stupid and not advisable but I didn’t have the proper tooling at time to remove clutch and fly wheel. Crank spins well now and is free from any debris got a new piston on there seal everything up and start leak testing fixed a few spots on the reeds and replaced crank seals but somthing is still leaking? I noticed it would hold 6 psi for about 3 minutes with the clutch side cover on but after I took it off it’s not holding pressure at all 1-2 psi drop in a minute. I thought it was coming from the crank collar so I put some rtv in there and nothing still leaking I thought it was coming from there but I think it’s actually coming from inside the case like in the transmission??? I seem to be able to hear somthing inside that little hole on top that I circled? I am working on splitting the cases right now
Struggling with leak down test
- Thread starter Benswoleson
- Start date
Sounds like you may find that piston debris jammed between the crank and case and may have cracked the inner case. Hopefully that's not what happened but splitting the case to look for the cause is about your only option at this point.
Would be a good idea to replace the crank and counterbalancer bearings while the case is apart, whatever you find. If you end up needing a case half or a whole case, it shouldn't be too difficult to find, Blasters had a good long production run.
Would be a good idea to replace the crank and counterbalancer bearings while the case is apart, whatever you find. If you end up needing a case half or a whole case, it shouldn't be too difficult to find, Blasters had a good long production run.
Update: split the cases and I don’t see any case damage so far there’s a tiny tiny scratch on the bottom of the crank but that’s all the damage I see to that. The case gasket was completely wallered out lmao and the section i highlighted was basically disintegrated and I can’t imagine it was doing a good job sealing that area what do you guys think? Do I need to replace the crank? I’d like to save the money if possible but if it won’t run without it I will, hopefully I can just seal the cases and that bad area and call it a day with this stupid ass leak, any advice is appreciated greatly thank you!
The case seems to be okay in the crank area, there is a small hairline crack on the aft side of the engine I’m assuming from chain slap but I can fix that at a later time, it seems the gasket was completely gone near the crank enclosure? Could that be the problem? It definitely sounded like the leak could of been coming internally from that approximate area
Sounds like you may have found the smoking gun. 
I would highly recommend using Threebond, Motoseal along with you new case gasket when you reassemble. Not silicon based Permatex. The gray Threebond or Motoseal is also meant to be an adhesive and works very well. In fact those types of sealant/adhesives are used by manufacturers of many newer engines that don not run a gasket between the case halves. Just be sure and clean all mating surfaces with brake clean or a similar cleaner that leaves no residue. To apply the sealant, I've always used my finger. A thin coating on both mating surfaces will ensure a good seal and also helps keep the gasket properly in place while assembling the cases.
You're on the right track
I would highly recommend using Threebond, Motoseal along with you new case gasket when you reassemble. Not silicon based Permatex. The gray Threebond or Motoseal is also meant to be an adhesive and works very well. In fact those types of sealant/adhesives are used by manufacturers of many newer engines that don not run a gasket between the case halves. Just be sure and clean all mating surfaces with brake clean or a similar cleaner that leaves no residue. To apply the sealant, I've always used my finger. A thin coating on both mating surfaces will ensure a good seal and also helps keep the gasket properly in place while assembling the cases.
You're on the right track
