Wiseco wrist pin question

[hawkman222]

Last spring I tore down and rebuilt a 1984 90 Hp crossflow. I saved 3 pistons and connecting rods from that motor with the hopes of using them at a later date. The pistons are Wiseco 3173P3 's, .030 over, and mic out well for round. I now have another V4 I'm working on and am thinking about using these pistons. I removed the wrist pins to check the rod small end and bearings. It didn't take much effort to remove the pins, and when I reassembled them, I could almost press the pin clear in with just my fingers. The fit is snug, but compared to the cast pistons I've used in the past, these pins seem loose. Is the pin fit looser in forged pistons than cast? Should I reuse these pistons or junk them? Would buying new wrist pins make for a more snug pin fit? Thanks!

 

[hawkman222]

Re: Wiseco wrist pin question

Not sure it matters, but the actual # off the pistons is 3013P3. The number I listed above is one I got off the web site this morning. I think 3173P3 is the new part number for the same piston.

 

[mikesea]

Re: Wiseco wrist pin question

tHEY DO PUSH IN EASY,NO TAPER,BE SURE THE CLIPS ARE WELL SPRINGY IF YOU REUSE THEM.i HAVE PUT HUNDREDS OF wEISCOS IN EVErY OUTBOARD THEY FIT THE SAME.i DO FEEL BETTER ABOUT THE XFLOW RETAINER WHICH SEEMS BEEFER,BUT NEVER HAD ONE FAIL.jUST ANOTHER POINT OF INFO.After all bearings are in ,on loopers,it appears that there is a bit of ,play if you try and seperate the installed bearings with a pick,I always did that in event I dropped a needle during assy..Its normal.The yamahas and xflows,had no play,but loopers for some reason is different.Unless you see bad scoring ,reuse,I suggest new rings

 

[hawkman222]

Re: Wiseco wrist pin question

Thanks, I feel a little better now about using them. New rings and I was going to go ahead and get new cir-clips. Have you ever used Spiro Lox retainers in place of the standard cir-clips? They seem fairly popular.

 

[mikesea]

Re: Wiseco wrist pin question

Never heard of them.We always used the piston kit,piston,pin,cir-clips.Glad to hear you getting new circlips.be sure to break the eng in slowly,the wiescos supposedly need a better break in,we always used double oil,either mix,or oil inj.and 50-1 in gas also.we liked to do more idle in beginning ,frankly I dont recall the process,but we were on the water repair shop and would let the boat idle for hrs with a few runs ,not wot in between.also,be sure to use a weisco for the 4th piston too

 

[Dhadley]

Re: Wiseco wrist pin question

The groove in the piston is cut for the Wiseco clips, nothing else. I wouldn't use the Spiro Lox. I've used them in GM motors but they were designed for that particular piston.

Yes, you'll be able to slide the pin thru with your fingers. Wiseco spent a ton of money on the machine that hones the pin hole to get that feel.

The 3013 is a very old piston. Back in the late 80's the number was changed to 3073 then in 2001 to 3173.