Rod to crankshaft clearance?

[jimmyebay]

1987 johnson 175. Anyone have ball park clearance with feeler guage from big end of rod to crank side?

 

[boobie]

No spec that I know of.

 

[boobie]

No spec that I know of.

 

[jimmyebay]

Couldn't find one. Can ya answer this? Do notice the rods have slight amount of metal rolled up around the outer edge of big ends. Not sure been ran low on oil before. Vro bypassed but before project started, someone had slid 2 new pistons in it so maybe starved for oil before I got it. Or is the metal rolled up normal? Doubt it...

 

[boobie]

Can you post a pic ??

 

[jimmyebay]

No Title

 

[jimmyebay]

Can you post a pic ??

Here's a picture. See the edges? Thinking About assemble and run it. Has slight thud noise when intake half is on and rotate crank. Almost like rod catches crank. Hard to explain but when running, would think be fine.

 

[daselbee]

You are going to blow it up if you run it with any thud sounds in the rotating mechanism.

My guess on the thud is that there is an edge hanging on a roller bearing somewhere....either rods or crank.

I had a thud once....V6 looper....I had to dress the crank saddles (both halves) very carefully with a file to fix that thud..roller bearing was catching ever so slightly.

I suspect the thud is related to the metal rolled out you are seeing, but I cannot tell from the pics.

 

[bob johnson]

that cant be good...but maybe it was caused before the last rebuild. personally, id deburr those edges, lest they flake off and get under a bearing.

bob

 

[emdsapmgr]

Did you overhaul this engine or buy it that way? Since you are this far apart, pull the rod caps off and have a look at all the crank rod needle bearings. Any of them blue in color ( a sign of overheating-throw them away.)

 

[Faztbullet]

Before yo uloosen rods back the heads bolts and gasket away from block, it it quits the piston is hitting gasket and possibly bored off center

 

[V153]

Before yo uloosen rods back the heads bolts and gasket away from block, it it quits the piston is hitting gasket and possibly bored off center

Good idea to loosen the heads FB. Hadn't thought of that. Yet ...

 

[jimmyebay]

Sorry for delay update. I am rebuilding this. Pulled crank. Took dremel and took knife edge off sides of crank journals for the rods. Got good used rods. Installed them. Back together. No more noise. Haven't ran yet. Ordered the check valves in the intake for believe called lube tubes. They either don't flow at all or both ways. Thanks for the help guys

 

[boobie]

They're called recirculation valves and only flow one way. Procedure in service manual to check them out.