Lil' Blue Rude
Well-known member
Yeah the plugs right but personally I'd get a newer set then that. Those are off of a 70's maybe early 80's model. Not a hundred percent sure they'd work for you.
TinBoats.net
The original aluminum boat site!
Jet drive ??"s
- Thread starter BigTerp
- Start date
Help Support TinBoats.net:
Lil' Blue Rude said:
Thanks!! They do look rather beat up as well. Now that I know what I'm looking for I've found a few sets of newer ones on Ebay for around $150. Much better shape as well. Probably hold off and pick up a set of those when the time is right.
Just a quick update.
My buddy and I tore into the jet a few weeks ago. Everything looks really good. Will need a new water pump impeller and we will go ahead and replace the water pump along with it. One of the piston heads has a crack in it, which we knew prior to purchasing. What is weird is that one of the clyinders is bored out .20 but the other is not. I'm guessing someone half-@$$#% a rebuild previously? We are also guessing that this is what caused the piston failure? I would think having one cylinder .20 larger would cause come compression or balance issues. I've talked to a few motor guys who suggested this caused a head gasket failure allowing water in and the motor hydrolocked which cracked the piston. Makes sense I guess.
Either way, everything else is in pretty darn good shape. No signs of overheating or excessive wear. The front right side of the leading edge of the jet foot is broken off. Just the corner piece, if that makes sense, doesn't go back to the itake grates. Will she run ok like this? Another questions I have is there is a slight bit of play with the drive shaft. I think I remember reading this is normal, but I'd like to confirm.
Power head goes to my buddies motor guy this weak for a cylinder boring. He is going to bore both out to .30 over. Then the rebuild can begin. I'll be sure to let you all know how it goes.
Thanks again for all the help!!!
My buddy and I tore into the jet a few weeks ago. Everything looks really good. Will need a new water pump impeller and we will go ahead and replace the water pump along with it. One of the piston heads has a crack in it, which we knew prior to purchasing. What is weird is that one of the clyinders is bored out .20 but the other is not. I'm guessing someone half-@$$#% a rebuild previously? We are also guessing that this is what caused the piston failure? I would think having one cylinder .20 larger would cause come compression or balance issues. I've talked to a few motor guys who suggested this caused a head gasket failure allowing water in and the motor hydrolocked which cracked the piston. Makes sense I guess.
Either way, everything else is in pretty darn good shape. No signs of overheating or excessive wear. The front right side of the leading edge of the jet foot is broken off. Just the corner piece, if that makes sense, doesn't go back to the itake grates. Will she run ok like this? Another questions I have is there is a slight bit of play with the drive shaft. I think I remember reading this is normal, but I'd like to confirm.
Power head goes to my buddies motor guy this weak for a cylinder boring. He is going to bore both out to .30 over. Then the rebuild can begin. I'll be sure to let you all know how it goes.
Thanks again for all the help!!!
So FINALLY got the pistons in last week and the powerhead is currently at the machinist. Hoping to have it back this week. My buddy travels almost weekly for work, so between that and waiting for the pistons to come in (which took forever) the motor is still waiting to be reassembled. I also still have alot to finish up on the boat. Was originally shooting for August 1st to have her back on the water, but September 1st might be more realistic.
New piston. Never seen pistons that looked so fancy and had emblems on them. Hopefully I won't be seeing them again!!
New piston. Never seen pistons that looked so fancy and had emblems on them. Hopefully I won't be seeing them again!!
Anything else I need to be checking out regarding my rebuild? Besides the obvious things that need replaced (water pump, gaskets, etc.)
Been checking out Chris Carsons reeds, and am considering getting a set. He offers sport, drag and racing reed sets. What would the difference be between the three and should I be looking at one over the other?
Been checking out Chris Carsons reeds, and am considering getting a set. He offers sport, drag and racing reed sets. What would the difference be between the three and should I be looking at one over the other?
Lil' Blue Rude
Well-known member
did you add extra clearance to the cylinder since wiseco's are forged? Forged pistons need more clearance then a cast piston because the forged piston expand more at operating temp. As far as the reeds go probably the sport reeds. Think they'll last longer and are more of a recreational use reed. but you can ask Chris. he's great to deal with and I'm sure he'll tell you just about anything you want to know about the reeds.
My buddy is in charge of the rebuild. He's rebuilt many dirt bike engines in the past. I asked him about the cast vs. forged and he confirmed that the forged needs a bit more clearance. So I'd imagine he passed the info. on to the machinist. He also uses Wiseco pistons in his dirtbikes. The same machinist he uses for his dirt bikes is doing the jet powerhead, so I'm sure he knows what he is doing. The Wiseco pistons should also come with a sheet that states reccommended clearances.
I admit, I don't know much about engines. Been learning alot through this process though. It looks like forged pistons are stronger than cast, and not as brittle? What are the other pros and cons between the two? Not that I'd change anything at this point, just curious.
Thanks for the suggestion on the reeds. I'll try and get in touch with Chris to see what he thinks.
I admit, I don't know much about engines. Been learning alot through this process though. It looks like forged pistons are stronger than cast, and not as brittle? What are the other pros and cons between the two? Not that I'd change anything at this point, just curious.
Thanks for the suggestion on the reeds. I'll try and get in touch with Chris to see what he thinks.
Lil' Blue Rude
Well-known member
The forged pitons are normally a little lighter and stronger. Down side is they grow more then a cast piston at operating temp so they need more clearance meaning they have more slop in the bore until they are at operating temp. So you need to make sure the motors had enough time to warm up before taking off. Not to say you don't need to with cast pistons to but there's just more room for the forged pistons to rattle around in the cylinder then the cast pistons do when not at operating temp. At least that's what I've been told and read about. Kinda makes sense.
Thanks Blue. I've read the same thing regarding the slop in the bore. I've heard some say they can make a sort of diesel engine noise until they get warmed up. Anxious to get the block back so we can finish up the rebuild!!!
Similar threads
