# Trouble adjusting truss rod in Yamaha FG-800M Acoustic



## TyGuy (12 mo ago)

Hi folks. I just joined. I'm a beginner guitarists, acoustic for now and was wondering if anyone has had an issue adjusting truss rod on Yamaha FG800M guitar. I bought it used looks in new condition but action is wrong strings vibrate against neck, etc. Tried adjusting with 7/32 hex key as recommended online. Seems to fit at 1st but when I turn it, it seems to slide against the teeth inside truss rod. Is it possible it's stripped and none fixable? Any help would be greatly appreciated. Thank you!


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## Alan Small (Dec 30, 2019)

It can work...will take some back n forth and certainly you may have been given the wrong size allen key...the correct size is important for sure...the nut is soft metal and one can "wiggle or tap in" the proper size and be happy...


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## TyGuy (12 mo ago)

Alan Small said:


> It can work...will take some back n forth and certainly you may have been given the wrong size allen key...the correct size is important for sure...the nut is soft metal and one can "wiggle or tap in" the proper size and be happy...





Alan Small said:


> It can work...will take some back n forth and certainly you may have been given the wrong size allen key...the correct size is important for sure...the nut is soft metal and one can "wiggle or tap in" the proper size and be happy...


Hi. I have a whole set and couldn't adjust with either of them. But as you said may take more effort to insert allen key into truss rod before adjusting. Will give it a try. Thank you!


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## Alan Small (Dec 30, 2019)

If you have an old model the access is in the headstock and requires a socket(nut) driver...also proper size is important


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## Alan Small (Dec 30, 2019)

A couple pics may help...

Also, no offense, you may think the truss will raise the strings and it WILL NOT....

If the strings are too close and buzz you would first consider raising the saddle just a wee bit...you can cut a hard plastic shim from a clear fruit food store container or, if thicker is needed, layer them or use an old bank card? This is temporary til you can buy a new taller saddle...


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## Alan Small (Dec 30, 2019)

The truss will.only raise or lower the fretboard around the 8th fret...if you are buzzing from the 10th to the 18th or so then the saddle height is the correction first


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## Alan Small (Dec 30, 2019)

A twonie plus a nickel should fit the space here(without a proper ruler the coins will do fine)


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## TyGuy (12 mo ago)

Alan Small said:


> If you have an old model the access is in the headstock and requires a socket(nut) driver...also proper size is important


Hi. No mine is through the headstock


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## Alan Small (Dec 30, 2019)




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## TyGuy (12 mo ago)

TyGuy said:


> Hi. No mine is through the headstock


not through head stock I meant


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## Alan Small (Dec 30, 2019)




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## Alan Small (Dec 30, 2019)

Inside guitar body....ok...allen key for sure...should be 5mm according to old yamaha info








but 8mm is more common


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## Smylight (Jun 28, 2016)

Certainly not a SAE size. Metric, either 4 or 5mm. Unless this Yamaha is from the 60s… 

Use the right size or you'll ruin the adjusting nut and end up with a fat bill from your friendly neighbourhood guitar tech. It can be a dog to fix when the nut is badly mangled.


Pierre
Guitares Torvisse


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## Acoustic Tom (Apr 6, 2020)

You said in the post that you are a beginner guitarist. I think it would be wise to take the guitar to a local luthier or shop and get them to set it up properly for you. Spend a few bucks now, then you can concentrate on your guitar playing with the confidence of knowing the neck wont be an issue.


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## ga20t (Jul 22, 2010)

Current FG-800 (green label, made in China, nato/okume back & sides, spruce top, rosewood fingerboard & bridge etc.) requires a 4mm wrench, same as my FG830. If you want to introduce some relief, turn that counter-clockwise and the opposite if you need to go back a bit. 

I'd be more interested in seeing a pic of your saddle and the string height at the 12th fret (with a ruler held on the 12th & 13th fret).


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## Latole (Aug 11, 2020)

You wrote; Tried adjusting with 7/32 hex key as recommended online.

1- where on the neck 7th, 8th, 9th,
2 -with capo on the first fret or not ? 

Most of the time space between fret and strings are where you have the more space 
And most of the time it is with capo on first fret

Turn allen wrench nor more than 1/8 turn and wait fews hours before take a new reading.
Some guitar neck may take 5 minutes before being stable some other takes few hours and more


Or follow advise no 14


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