Con Rod Install Questions

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JTSpeedDemon

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:huh:
Please explain the reasoning behind that.
I would think thicker oil would be good for less clearance so it doesn't run off as quickly.
 

Randy H

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My reasoning is that a thicker oil might not flow into the bearing surface as well as a thinner weight oil. Given tight clearance.

I could very well be wrong. Experiment.

If it was mine and the clearance was actually .0015". I would polish the crankshaft, or hone the rod or both.
 

JTSpeedDemon

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Would a standard spring loaded hone work to hone the rod? As long as it fits in the bore of course. Right?
 

JTSpeedDemon

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I would think another possible solution would be to apply fine lapping compound to the journal, tighten it down, and rotate it a bunch to get a little more clearance.
Thoughts?
If that 0.0015 measurement was accurate(which I will verify tomorrow once the crank is removed), I should be good, but I'll make sure to use slightly thinner oil.
THAT GUY IN THE SECOND LINK SEEMED TO BE YELLING A LOT!:roflol:
 

Randy H

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That would increase clearance.

I might give that a try. But I've got a big pile of parts, with not much money invested.
 

JTSpeedDemon

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Yeah I've found my parts pile to be steadily growing.
Ah well, it's part of the addiction. :D
If the clearance is unacceptable(doubt it), I'll probably buy a 555207 off of ya.
 

Randy H

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Hopefully it's good.

Of course at governed RPM good and tight is just ducky. Start increasing the RPM and the potential for heat buildup and the rod seizing on the crankshaft becomes more likely.
 

JTSpeedDemon

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Oh yeah, I checked the governor arm throw, or "floppage".
Here's what I found:

Even at the points where the exterior governor arm hits the block, the interior governor arm does not touch anything.
So if someone else wants to know, it's perfectly acceptable to remove just the governor gear and reuse the factory throttle linkage.
Especially with the normal amount of throw the arm has.
PLEASE NOTE: this ONLY applies to the sidecover interior mounted governor gears!

---------- Post added at 07:53 AM ---------- Previous post was at 07:20 AM ----------

Well, I went and bit the bullet.
I bought a 19244 starter clutch wrench. Mainly because I don't want to risk under torquing the clutch, as this engine will be spinning in excess of 5K sometimes.
That, and I don't want to damage it.
So I went ahead and got one day shipping($13 :eek:).
So today I'll just relax and tidy up the insanely messy workbench, and tomorrow or the day after that, I'll remove the flywheel so I can remove the crank and camshaft, to get accurate oil clearance readings.
 

JTSpeedDemon

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Hmmm, interesting.
https://www.ebay.com/itm/Briggs-Str...=333019037003b1ca74eef5c9434f94f196b2202c2a72

It says the part number is 299430(the OEM replacement for my engine), but the pic shows a Raptor II/III rod. *shrug*
Whether they've got the number wrong, or the pics wrong.

Also, I found out that my stock rod has the good black oil dipper, so yay! I'm just gonna keep it for parts, unless I can sell it for a reasonable price on Ebay.
Starter clutch wrench came in, so I can remove the crankshaft tomorrow, and tonight I'm gonna pick up some 400 grit sandpaper to clean up some scoring in the cylinder.
Things are chuggin' along!
 

JTSpeedDemon

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Hissss!! Don't want made in China!
If there's ever a time when I can't acquire an official Raptor rod, this would be better than the stock bolt on dipper rod.
 

JTSpeedDemon

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So, I know that the oil clearance is at least 0.0015". Perhaps a little more.
That is right on the minimum end of the clearance scale. Should I worry? Or should I just run some thinner oil and ride it?
I also think I'll install a tach so I can cruise at safer speeds if I want.
Does this all sound reasonable to keep it from blowing or seizing up? I would be absolutely demolished if I ruined the block.
 

Randy H

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I believe a big cause of a rod seizing to the crank, breaking and windowing a block is because of tight clearances. Especially at higher than governed RPM. Guessing at clearances is a poor practice.

A lot of guys seemingly take great pride in guessing and destroying parts. "Look at me I made great power, my block is in two pieces." In some cases they may have. In others the clearances were way off.

I know they're are plenty of videos where guys happily toss parts together.

I think it would be a shame to wreck your block.

Where are you at in the flywheel removal process?
Let's find a way to do this right.

Personally I'd be a bit concerned about a bearing that was grinding too. It's your baby though.
 
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