Replacing the wrist pin bearing

[Scooterspal]

I'm trying to track down a rattle noise on my Spree and have two questions:

The wrist pin bearing is the one at the top of the connecting rod under the piston, correct?

Is it necessary to remove the engine from the Spree in order to replace it?

[Wheelman-111]

Greetings:

Scooterspal axted:

Is it necessary to remove the engine from the Spree in order to replace it?

Removing the engine only takes a few more minutes and saves time because you don't have the frame in the way, but it's not mandatory. Skins, Exhaust, spark plug, cooling shroud, and 4 head bolts allows you to lift the head, then the jug. Piston off exposes the top end of the conrod and its bearing. If the rattle is from the top end, a new bearing and/or piston pin and/or piston & bore will correct. Hopefully the noise isn't from the big end. Little more trouble there...

[Scooterspal]

Much thanks.

I will try and locate the source using an old stethoscope before I take anything apart.

[noiseguy]

I'm trying to track down a rattle noise on my Spree

Check for an exhaust leak 1st.

[dreamer1uk]

Hi,

My 86 Spree is making some unusual noises too, like a constant clicking noise. I hope to pull the head after work on Wednesday and see whats going on.....and i just got the Scoot a month ago too

[Scooterspal]

Was not the bearing. Noise vibration from something else... cover, plate. Anyway it is now gone away.
Thanks!

[Wheelman-111]

Greetings:

That thin metal cooling shroud can make frightening noise! Glad you've resolved it.

[itzmepete]

Wheelman, how hard is it to replace the connecting rod bearing at the crankshafts end? I popped my engine apart due to bad crankshaft bearings. I am ordering new crank bearings, seals and want to replace the connecting rods bearings as well. The piston end is a snap but whats the deal with the crank end? Is that pin pressed in or what?

[Wheelman-111]

Greetings:

itzmepete Axt:

Wheelman, how hard is it to replace the connecting rod bearing at the crankshafts end?

I'm flattered that you'd ask me but I've never tried and probably never will. Y'see despite my sturdy Granite Rock and my Oaken Stick, I'm not particularly well-equipped to attempt such an undertaking. Unless your name is Soichiro and you have a large Foundry and Industrial plant somewhere in Japan, you probably aren't either.

Even in the unlikely event that you'd find the Massive Press necessary to push that crankpin out, getting everything back around your new bearing to fit true in the Bank, Pitch, and Yaw axes is a Black Art best left to grizzled toothless men with lots of faded tattoos. I'm betting Honda uses Really Big Machines with computer-controlled pin-point accuracy for this critical part.

If you have the precision measuring instruments to do so, measure the bearing for thrust and wobble (sounds like a date I once had... ), make sure it spins smoothly and call it good. If not, I strongly recommend you source a good crank, pre-assembled for your building convenience.

If you decide to get some tattoos and knock out a few teeth, please do post your outcome for all! I mean your crankshaft
outcome...

[itzmepete]

Yeah well my crank bearings went out so it could have knocked my crank out of true. On top of that I smacked it a few times with a brass hammer and it started to seperate. Anyway, I knocked it back, clearance wise seems fine, I slapped a feeler guage, but true I don't know. Anyhow, wanting to keep costs down as a new crank assy costs $161, I went to work and chatted with a guy that was just hired and worked in a machine shop. I am an aircraft mechanic and we do run outs and dial calipers and all that stuff but I don't have V blocks, we do stuff like that on the plane. Anyhow I asked him and he quickly said no problem, lol. He said he has V blocks and all but his slate is at home and he will bring it in. Asked what tolerance I said within .001 and he said I'll get it at .0005! So the plan now is to just make sure its true, if not, smack it back and forth with the brass hammer, true it and not mess with that bearing as it feels good anyway.

I'll let you know what happens and thanks for the tip!

Pete

[Wheelman-111]

Greetings:

You're welcome, and evidently fortunate to have such a friend. Ax to see his tattoos.

If you can't get yours straight, good used cranks fall out of Sprees around here all the time. They typically fetch around $50, give or take.

[CharlotteSpreeRider]

If your friend is good at magically transforming out of true cranks into pristine cranks, we may be able to supply said friend with a side business. I have at least two cranks in the garage that fit this description right now.

[itzmepete]

I will let him know for sure! He is always boasting about his dial indictators, micrometers and what not so I will put him to the test!