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DISCUSSION => Engine + Driveline => Topic started by: elementskater_xx on May 06, 2008, 09:18:05 PM

Title: Engine backlash???
Post by: elementskater_xx on May 06, 2008, 09:18:05 PM: So what exactlly is backlash? The guy rebuilding my head said that I have backlash and it's going to take 3 extra days to fix. What the #$&^ is it?
Title: Engine backlash???
Post by: nomad on May 07, 2008, 12:51:10 AM: Dunno?
Title: Backlash
Post by: nicknikolovski on May 07, 2008, 05:00:25 AM: I have never really heard of backlash on an engine before.

Backlash is usually associated with gear meshing example in a gearbox or a differential. It relates to excessive clearance between gears causing a kind of looseness in the components.

When you get the car back, ask the guy what he meant by engine backlash.
Title: Engine backlash???
Post by: Cobra Jet on May 07, 2008, 09:34:04 AM: from my interpretation, your guy only has the HEAD from the engine - right? If so, call him back and ask him to "explain the backlash" and what part of the head has the backlash he's telling you about...

Did you bring him the complete head w/ valvetrain still attached?
Title: Engine backlash???
Post by: nomad on May 07, 2008, 10:16:40 AM: maybe he means the bearing surfaces on the cams are worn down? The valve seats are worn down?

Pick his brain and enlighten us. It's not costing any additional money is it?
Title: Engine backlash???
Post by: elementskater_xx on May 07, 2008, 04:48:57 PM: It was the hydralic lifters (the shiny metal caps above the springs between the cams and springs) it's when all the oil drains out. So he but fliud in it for me. It costed me a total of $615. But it's home and the rebuild starts in like 20 mins i will post up some pics.
Title: Engine backlash???
Post by: peerless on May 07, 2008, 07:27:50 PM: $615 for the cylinder head?

What all did you have done?

My guy only charges me $200 to do these heads. That includes replacing valve guides, valve job and resurface. I supply the parts he needs. Although I strip the heads of the cams and lifters before I take them in.

Good luck on the engine build

Quote from: elementskater_xx;48861
It was the hydralic lifters (the shiny metal caps above the springs between the cams and springs) it's when all the oil drains out. So he but fliud in it for me. It costed me a total of $615. But it's home and the rebuild starts in like 20 mins i will post up some pics.
Title: Engine backlash???
Post by: Letsplayskatch on May 07, 2008, 07:35:41 PM: Quote from: elementskater_xx;48786
So what exactlly is backlash? The guy rebuilding my head said that I have backlash and it's going to take 3 extra days to fix. What the #$&^ is it?

Assuming youve given him the head, plus all valves,springs etc, then backlash means there is 'play', or 'looseness' in your head. Everything will chatter if you try to run it again.
He'll probably lap the parts in (a process using cutting paste to 'seat' the valves into the head properly), or add material (TIG weld) where there might have been serious wear issues.
Title: Engine backlash???
Post by: Cobra Jet on May 07, 2008, 09:09:20 PM: before you slap that rebuilt head on to your engine block, I would definitely check the engine deck for ANY warpage at all... the slightest deformation on the deck will only create havoc for you in the end once it's all buttoned up again (ie: head gasket failure)...

best of luck w/ the rebuild too!
Title: Engine backlash???
Post by: nomad on May 08, 2008, 12:35:48 AM: Oh, also, before you put the head back on, clean every little area you can find where there may be metal shavings hiding.