Checking Backlash??? Nissan NS30A3

[ARC240]

Hi everyone. I've just finished reassembling my lower unit on my 1992 NISSAN NS30A3 after replacing seals and the driveshaft/input shaft bearing (under the waterpump), now I'm getting ready to check backlash. I have the Nissan FSM for this outboard and it shows you how to check it, however it says that you need to use a "special tool" clamped onto the driveshaft (that costs around $150...for a 1-time use, which I see as a wasted purchase). I've seen people checking backlash different ways (searched internet already ) without the special tool, but I'm not certain on those methods and can't get a real definitive answer. Can anyone give me any suggestions? Any help is appreciated, thanks very much!

 

[TOHATSU GURU]

Re: Checking Backlash??? Nissan NS30A3

You need a dial indicator to do it correctly.

 

[ARC240]

Re: Checking Backlash??? Nissan NS30A3

Understood, I have a dial indicator. What I don't have is the "special tool" they refer to in the manual that clamps onto (and extends from) the driveshaft. Almost looks like a piece of wire that extends from the d/s that the dial indicator gets it's measurement from. Is there any way to get around using that wire/clamp contraption (or making one of your own) or is it possible to use only the dial indicator?

 

[ARC240]

Re: Checking Backlash??? Nissan NS30A3

Anyone have any other suggestions? I've been looking around for the proper method to this all week and haven't found a thing, really starting to become more frustrating than anything else. Trying to get the boat ready within the next week or so. Thanks for the help thus far, any added info is greatly appreciated!

 

[pvanv]

Re: Checking Backlash??? Nissan NS30A3

If you can cobble up a couple of square rods with cross bolts, that will work. The idea is to amplify the amount of lash/rotation so you can read it easily on a dial indicator, and to get the reading out to where you can mount the dial indicator.

 

[ARC240]

Re: Checking Backlash??? Nissan NS30A3

Thanks very much for the reply. Hmm, is it possible to use the backlash extension rod for Mercury outboards? I know the 30hp mercs of the 90's were the same as Nissan/Tohatsu. Would something like this: http://cgi.ebay.ca/Mercury-Outboard...at_Parts_Accessories_Gear&hash=item20b831ee13 work? These are available at my local marina so if it would work, that would be excellent! I have the dial indicator, just need the backlash rod.

 

[pvanv]

Re: Checking Backlash??? Nissan NS30A3

If you can get it to clamp on the shaft, you should be fine.