found wood in the air box!

[dansmith65]

It looks like it's meant to hold the intake tube in place. Maybe the tube got warped/lost its shape at some point? I'm assuming that chunk of wood is messing with the airflow, but if I take it out I need to find an alternative way to hold that piece in place. Any thoughts/ideas?

[DiverRay]

That goes into the "dirty" air side. You could pull the snorkle and clean everything up with alcohol, and then glue it into place. Use the wood while the glue dries. I would use the 3M weatherstrip glue.

[dansmith65]

Thanks again; sounds like a good idea. I've never heard of that 3m weatherstrip glue before, but I looked it up and sounds like useful stuff!

I recently found Seal-All in a local store and probably would have used that if I hadn't heard otherwise. Has anyone here used Seal-All before?

[MPittma100]

Adhesive

Thanks again; sounds like a good idea. I've never heard of that 3m weatherstrip glue before, but I looked it up and sounds like useful stuff!

I recently found Seal-All in a local store and probably would have used that if I hadn't heard otherwise. Has anyone here used Seal-All before?

Not used seal all. The 3M w/s adhesive comes in black also.

[Radioguylogs]

Seal-all is good stuff

I use Seal-All semi-regularly.

It's the best product when gas is involved.

I think weatherstripping glue might be better for your job. Seal-All sticks well to almost anything, but it can peel like silicone glue in a flexible application like yours.

[dansmith65]

Thanks for the feedback. Good to know why Seal-All isn't a good fit here, and what it is a good fit for. I've got some 3M weatherstripping glue on it's way to me now.

While I'm at it, I think I'm going to soften the velocity stacks via a Wintergreen/Alcohol soak.

[Geezer]

The snorkel is only there to quiet the intake roar. Most people don't notice a difference if it's left off...

Tony

[Mathh]

The snorkel is only there to quiet the intake roar. Most people don't notice a difference if it's left off...

Tony

The snorkel is there to suck air where there is the least turbulance: under the seat. I know the European 78 models had an additional foam box like dampener added to the snorkel that fitted in the existing room under the seat. That was indeed added to quiet the intake noise. Yamaha stopped using it after that first year.

[TopCatGr58]

Well, I'm not so sure about the need for less turbulent air into the snorkel as much as possibly a bit cooler from back there vs RIGHT BEHIND the engine. Also stays dryer in the rain. Dan, see those long velocity stack intake tubes inside the airbox that attach to the carbs, they are what helps to straighten out the air flow going into the carb throats neutralizing turbulence there.

T.C.

[Mathh]

Yamaha themselves call it : 2h71443101 Silencer, Air Cleaner.... so, obviously I guess I'm wrong

[motoman]

Good to see you still drop in on occasion Mathh!

[skids]

I would think that the snorkel has an effect on carburation, just as individual filters do (but to a different extent).

[motoman]

I would think that the snorkel has an effect on carburation, just as individual filters do (but to a different extent).

True, to a certain extent. Individual filter pods DO affect vacuum slide/metering rod location based on vacuum draw, when and how much. IMO, the snorkel possibly could affect air flow, and work similar to a velocity stack.

[dansmith65]

I case anyone is interested in the potential impact of airflow in this tube, here's a picture of each intake side of the engine: (in order from 1-4)

I'm new to this, but my take is that #2 is running leaner than the others. I've only got carb #4 apart so far, so I'm not sure if the carb is causing this, or what, just yet.

[DiverRay]

Do NOT pay attention to the engine until it's been run awhile WITH the valve lash properly set. You had valves WAY too tight, and that will cause problems with running, and the way things look.
I don't know how far down you want to take it, but I would guess the valve seals will be leaking soon, just from age. If you have time search this site for hints on replacing seals without removing the head. I'm pretty sure one or two owners have done it.
If not, it's cheaper to buy an overhaul gasket set and use what you need to pull the head and replace seals.