Rodbolt, rebuild question

[Masonmobilemarine]

Anybody can answer this.

2005 F225TXRD

Bought one to rebuild a bit ago. Measuring out the cylinder bores, I think I have 1 cylinder that needs to be bored out a bit.

Reading through the service manual it says that if a cylinder is out of spec to rebore that cylinder.

2 questions here.

1). The way it is written it indicates it is singular...as in only rebore that one specific cylinder. Is it acceptable to rebore just one cylinder oversize and run STD piston/bores in the other cylinders? I've always bored all my cylinders out the same size.

2). It appears that yamaha does not even sell oversized pistons/rings. Why would they tell you to bore it out (opposed to sleeving) if they don't even sell the part for it?


Extra question: Where do you buy your oversized pistons/rings from?

[boscoe99]

https://www.boats.net/search?q=69J-11635-00-00

[panasonic]

This post may have your answers
http://www.yamahaoutboardparts.com/f...xrr-bad-piston

[rodbolt17]

Yamaha,sierra and wiesco and a few others sell oversized pistons and rings.
the key is the macxhine shgop that bores it.
can they properly chamfer the ports?

[boscoe99]

What ports?

[rodbolt17]

ok, I did not catch the F.
as long as the cyl is bored a finished honed your good.
bearing selection can be a pain.

[Masonmobilemarine]

ok, I did not catch the F.
as long as the cyl is bored a finished honed your good.
bearing selection can be a pain.

So I can do just one cylinder instead of having to do all 6?

[Masonmobilemarine]

https://www.boats.net/search?q=69J-11635-00-00

Hmm...interesting.

When I search for it by year (2005) it doesn't have anything OS listed on there.

Looking it up by HP now has the OS piston listed there...odd. Well, if I look up an F225TXR...it has them. IF I look up a F225 TXRD...it doesn't show them.

[Masonmobilemarine]

This post may have your answers
http://www.yamahaoutboardparts.com/f...xrr-bad-piston

Problem is that is a 2 stroke. Mine is a 4 stroke. I know its commonly done (reboring a single cylinder) on a 2 stroke....but don't hear about it much on a 4 stroke.

[panasonic]

I thought rodbolt would confirm. But when he was pointed out that it was a Four Stroke he didn't say any different...maybe he will confirm.

I don't think it would be a problem. I have weighted stock pistons from bike engines and they were different weights. The Wiseco replacements I replaced them with were very close to being the same wieght.

I know you want to be sure though.

[boscoe99]

If they needed to be matched wouldn't over size pistons come in sets of six for an F225?

Over sized by 0.25 mm. 0.00984". Not a lot of weight.

Aluminium foil bought in the supermercado is nominally 0.20 mm or so.

I think rodnut has mentioned several times that they do not have to be installed in sets.

[Masonmobilemarine]

If they needed to be matched wouldn't over size pistons come in sets of six for an F225?

Over sized by 0.25 mm. 0.00984". Not a lot of weight.

Aluminium foil bought in the supermercado is nominally 0.20 mm or so.

I think rodnut has mentioned several times that they do not have to be installed in sets.

That's a decent point .

I was able to get with my machinist...only machine shop that specifically does marine work....and only one that touches 2 stroke. He's machined hundreds of outboards. It's probably at least 1/3 of his workload.

Anyways, he said doing one is just fine.

I figured it would be, I just didn't want something getting off balance and then 100-200hrs from now getting wonky.

[pstephens46]

That's a decent point .

I was able to get with my machinist...only machine shop that specifically does marine work....and only one that touches 2 stroke. He's machined hundreds of outboards. It's probably at least 1/3 of his workload.

Anyways, he said doing one is just fine.

I figured it would be, I just didn't want something getting off balance and then 100-200hrs from now getting wonky.

Why didn’t you check with him first?

Is his name Floyd?

[Masonmobilemarine]

Why didn’t you check with him first?

Is his name Floyd?

I did...but being the weekend I didn't expect a reply. I texted him after hours Friday, and got a reply today, Sunday. I think it's good he even texts on his off time .

Not floyd

[pstephens46]

I did...but being the weekend I didn't expect a reply. I texted him after hours Friday, and got a reply today, Sunday. I think it's good he even texts on his off time .

Not floyd

Messing with you. Bit of an inside joke here.