Jump to content
HybridZ

Connecting rods backwards?


akeboshi

Recommended Posts

I guess my rod being backwards is a blessing in disguise. When I pull the rods out I saw that one of the bearings was chewed up on the edge. Turns out my crank was damaged in the raduis area of the journal. Damn, oh well, I already pulled another crank from the junkyard, The car it came from had 289K on the odometer so I will take some good measurements and inspect it more closeley.

Link to comment
Share on other sites

You think it's loud using 12 tons, try a Cameron MSG Impeller wheel about 24" in diameter (or hell, even the smaller C8's in the 8" range) that you heat the wheels to around 500F apply 100 ton press on a backing arbor and just keep heating. Yeah, it makes a "pop like a gunshot"...!!! :blink: A little bit of an interference fit there!

 

Yeah to answer your question, they could put them on any way they wanted. I have gotten piston sets back where (no aspersions here, but...) 1,3,5 were pressed onto the pistons correctly, and 2,4,6 were pressed on so the notches would face the 'back' of the engine! At least there I can ascribe it to working on "V" engines, or whatever... It was a logical mistake to make (I guess...)

 

The ones that make you worry are when there's no rhyme or reason to the setup---like they didn't even look at the rods and just pressed the pistons on willy-nilly in a rush. Those places give me the willies. Never know what to trust out of a shop that does that. My favorite places are where I know the guys, and we all come in on the weekend and do the work (which they still get paid for) but I'm there running the press or taking with the guy setting up the boring / honing machine. The labor takes a lot longer, but there usually is liquid discount applied after a couple of quick job runs and we take the rest of the day off. Takes a lot longer to get stuff done, but it's done right.

 

My kid came in the house last visit and said "Dad, do you need blocks hot-tanked? We got this machine were I'm working..." :)

Link to comment
Share on other sites

:mellow:

I trust our machine shop but then again, I could definitely see it being an odd mistake thinking they can be pressed in either way. If I could remember what the hell I did during the build or if I had pictures of it, I would get my answer! If I didn't check myself and just put the pistons facing the front well that's my own fault... My pictures went from block without crank, to block with head bolted down. hah

 

 

best of luck to you akeboshi. It's a good thing you had a back up crank.

Link to comment
Share on other sites

Ok, so I went ahead and bought new pistons and just installed the pins. I heated the small end of the rod up then pushed the pins though but on most of them I didnt get the pins all the way through. I used a press to push them the rest of the way through (using a piece of wood under the piston, in the small recess where the pin holes are)and now they feel tight. I was under the impression that they needed to move under their own weightlike loosey goosey. Did I do something wrong? I can move them with my hands just fine but they feel.... not right.

Link to comment
Share on other sites

Ok, so I went ahead and bought new pistons and just installed the pins. I heated the small end of the rod up then pushed the pins though but on most of them I didnt get the pins all the way through. I used a press to push them the rest of the way through (using a piece of wood under the piston, in the small recess where the pin holes are)and now they feel tight. I was under the impression that they needed to move under their own weightlike loosey goosey. Did I do something wrong? I can move them with my hands just fine but they feel.... not right.

 

Did you put some oil on the pin, where it fits in the piston, it may help

Edited by Noddle
Link to comment
Share on other sites

The piston/rod assemblies came from another motor. I didnt catch this when I was putting them in the new motor, then I saw the section in the datsun book about it and went to double check it. The piston was installed the wrong way from the old motor.

Old trick with the original pistons was to install them backwards (180 out) as it would run a little looser.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...