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Old 08-09-2009, 06:55 AM   #1
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Default con rod or crank pin?

I took off the backplate of my vspec to check the rod, and noticed that there was excessive play in the rod/pin. My question is, is the play comming from the bronze bushing in the rod or is it the crank pin?

Basically do i need to replace the rod or the crank?
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Old 08-09-2009, 07:04 AM   #2
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The rod is softer and wears faster but if its really worn it can take out the crank pin.

If its the crank pin, then you have to replace the crank, but you STILL have to replace the conrod anyway.

So I'd start with a fresh rod and test it on your old crank.
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Old 08-09-2009, 07:09 AM   #3
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thanx. How hard is it to change the rod out?
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Old 08-09-2009, 07:20 AM   #4
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Its easy. Hardest part is getting the head screws out without stripping them. Push real hard before turning.

Then just be careful pulling the wrist pin spring clips out. You can't just yank them out or they'll take part of the piston with them. You have to compress or wind them up a little. I haven't got a good technique for that yet. I'll let someone else chime in on that.....

And note the orientation of all the parts. You don't want to be the guy racing a vspec with a piston in backwards (worked, but ghost flamed out. Actually seen people do this more than once )
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Old 08-09-2009, 07:25 AM   #5
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Its easy. Hardest part is getting the head screws out without stripping them. Push real hard before turning.

Then just be careful pulling the wrist pin spring clips out. You can't just yank them out or they'll take part of the piston with them. You have to compress or wind them up a little. I haven't got a good technique for that yet. I'll let someone else chime in on that.....

And note the orientation of all the parts. You don't want to be the guy racing a vspec with a piston in backwards (worked, but ghost flamed out. Actually seen people do this more than once )
I am very familiar with my engine and it's parts. Just never replaced a rod. Bearings yeah. Oh piston in backwards = broken skirt. And i have never broken a head screw. I honestly don't know how people have such a problem with that. I do however replace them if they even look like they are not new. I have striped screws on the backplate though.
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Old 08-09-2009, 07:26 AM   #6
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also will a hole in the carb boot act like a air leak?
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Old 08-09-2009, 08:16 AM   #7
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bump for more info please
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Old 08-09-2009, 08:42 AM   #8
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A hole in the carb boot is a big problem. Replace it.

I use an oring, or if that deosn't work a small zip tie at the base of the carb boot to keep it sealed. the oring is gentler and won't lift the boot like an over tightened zip tie. Doesn't work on all engines.
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Old 08-09-2009, 09:35 AM   #9
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How much play are we talking about here? how many gallons you have on it? I ran my v-spec with a pretty good amount of play in it and it seemed fine. But I don't know what your situation is =X
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Old 08-09-2009, 01:41 PM   #10
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Originally Posted by dreaux View Post
I took off the backplate of my vspec to check the rod, and noticed that there was excessive play in the rod/pin. My question is, is the play comming from the bronze bushing in the rod or is it the crank pin?

Basically do i need to replace the rod or the crank?
On the Std. V-spec the crank usually wears almost as much as the rod. Best bet is to buy a Jx Ninja or Speed crank and rod, it will last much longer.

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Old 08-09-2009, 01:50 PM   #11
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How much play are we talking about here? how many gallons you have on it? I ran my v-spec with a pretty good amount of play in it and it seemed fine. But I don't know what your situation is =X
5 gallons. and it has a good amount of play. well you can see it wobbling in there at in and around tdc. I will be getting a new ninja this week. also if you have to replace the rod and crank, bearings etc. wouldn't you be better off getting a new one? a crank and rod is about 150$$ so that would be half the price. With tko's it would be closser to 200$ so i guess if you rebuild it with a speed crank you would have a better engine anyway. i guess when the P/S go you can get a pinch or replace it.
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Old 08-09-2009, 03:32 PM   #12
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I have pinched some friend's Speeds 3-4 times. I am not a big Os fan but the Dlc coating is awesome, only seen it worn through to silver on one motor ever. If you look for deals on Ebay I have heard of Jx cranks going for under $70.00.

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Old 08-09-2009, 04:54 PM   #13
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On the Std. V-spec the crank usually wears almost as much as the rod. Best bet is to buy a Jx Ninja or Speed crank and rod, it will last much longer.

Rex
i already told him the crank usually wears before the rod on the vspecs
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Old 08-09-2009, 05:03 PM   #14
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i already told him the crank usually wears before the rod on the vspecs
That stinks.

I thinks i'll be sticking with NR motors then.
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Old 08-09-2009, 05:06 PM   #15
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That stinks.

I thinks i'll be sticking with NR motors then.
good choice


not bashing vspecs at all , i love the short stroke , big bore design but the cranks just wear out pretty quick .

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