eroc144

My Feedback: (1)

How does one go about removing the connecting rod in a Norvel .074? I'm sure it's dreadfully easy, except that it isn't immediately obvious either (at least not to me), and I'd prefer not to booger up my nice engine.

If I pull on it directly will the bottom end detach from the crankshaft? Does the pin in the cylinder push out to release the top end?

Inquiring minds want to know.

EG

digital_trucker

Once you remove the backplate and the cylinder, the conrod should slide off the crankpin (you might have to use a toothpick to help it a little). Getting the wristpin out of the piston might be a little trickier....someone else here may know the answer to that. Of course, I can't think of any particular reason to remove the conrod from the piston anyways. If you're looking to clean it, soaking it in denatured alcohol for a bit and swishing it around will do nicely.

Tim Wiltse-RCU

eroc,

Don't tell us...you scored one off eBAy with a bent connecting rod right? Like DT stated already first you will have to pull the cylinder off the engine to get it off the crankpin. The pin will either be held in with little micro circlips like those used on a Cox reed valve engine uses to hold the reed but much much smaller of course or it will be peened into place at which point I don't believe you will be able to remove it. Norvel has used both methodes over the years so you will have to look at your first.

LAter,
Tim

combatpigg

My Feedback: (3)

Once you have the piston / rod assembly in your hand, you will need to make a fixture to do the job. Use a dremel drum sander to gring a concave spot in a piece of hard wood, then lay the piston on this rut with the staked side of the wrist pin hole facing down. Find a drift punch that fits the hole in the piston and tap the pin out until it makes an impression in your hard wood holding fixture. Drill out a clearance hole in the hardwood for the wrist pin to drop into, then go back to driving the pin out. To re-peen the new assembly in place, lay a small allen wrench across the hole with a sharp edge against the piston wall, and tap the wrench until you have deformed the piston enough to keep the pin in place. Check the piston wall with a straightedge, like an Exacto blade to see if you have left a high spot that would scuff the liner, if so scrape it out of the way. Make sure you have done a good enough job of staking the pin in place, or else it will back out and ruin the engine

eroc144

My Feedback: (1)

How'd you know that? Jeez you guys are smart! I've got several .074s and with nowhere to get replacement parts this one was a no-brainer. It'll be fun to see if I can straighten the conrod sufficiently to get max RPMs.

Sounds like all I have to do for the conrod / crankshaft connection is give it a pull. I'll start there.

EG

Tim Wiltse-RCU

I was just at my LHS and they had a NIP Norvel .074 cylinder and piston/rod set. So I took a look at it and the pin is peened in on BOTH sides[:@]

LAter,
Tim

gkamysz

My Feedback: (19)

Isn't every Norvel and Stels the same way?

Tim Wiltse-RCU

How'd you know that? Jeez you guys are smart!

EG
[/quote]

Your eBay name is the same as your RCU name

LAter,
Tim

Tim Wiltse-RCU

Your eBay name is the same as your RCU name

LAter,
Tim
[/quote]

Andrew

Hmmmm --

Did it look like this one?

It came up on the other forum as a question and I had responded to the owner.

combatpigg

My Feedback: (3)

Unless you go through the process of heat treating the rod so it can be unbent, I don't think a bent aluminum rod is repairable.

eroc144

My Feedback: (1)

I thought it was more like the one below. Probably a different engine...

I try to keep things simple. Too may userIDs and passwords make me confused.

The conrod came right off the crankshaft with nary a tug, but it turns out CP was right again - the bent aluminum rod wasn't repairable. 'least I still have lots of spare parts at a bargain price.

EG

digital_trucker

On both my AME .061 and my .074, the rod is peened on both sides...

robsib4

Looks like the same picture, just a morror image of each other.

Tim Wiltse-RCU

Naw...in one picture you clearly see his right hand and in the other his left!

P.S. the crank pin looks weird or is it just the picture?

LAter,
Tim

Andrew

Here is the original pic that I saw -- it was larger so I didn't upload it initially. I had noticed the crankpin too -- it almost looks as if it has been drilled.

combatpigg

My Feedback: (3)

It looks like some "dremel guru" had his hands in there. The face of the cranks' web looks like it was ground to resemble the top of a mushroom. He probably read where knife edging the crank throws on an automotive engine was worth some free horsepower.