Topic: Replacement gasket fitment on main carb jet (75 550K) — too big?

[PennyDreadfuls]

I bought the Honda replacement carb gasket set (16010-323-315) for my 1975 550K and most of the gaskets seem to fit well with the exception of what I thought was the main jet gasket (it's the only gasket included that is closest to the correct size).

Has anyone run into this issue before? Is it expected that it needs to get pressed in? Wrong gasket set perhaps?

(Ignore the jet orientation, just trying to show fitment issues)



carb bodies have 022A stamp:

[flybox1]

yeah, thats WAY too big.
IIWM, id take my jet and carbs down to the local auto store.  they usually have a good selection of metric buna or viton orings behind the counter in a case.  you might find one that fits for $.50    it should be a much tighter fit than whats on there now.  Just a finger smear of motor oil on the o-ring before you push it in to prevent ripping.

[reddyvv]

That's the right kit so you aren't using the correct o-ring. Two of them go on the fuel T-fitting, one on the drain screw and one goes on the float valve.

[PennyDreadfuls]

That's the right kit so you aren't using the correct o-ring. Two of them go on the fuel T-fitting, one on the drain screw and one goes on the float valve.

So are you saying that there isn't a gasket for the main jet in that packet?

[reddyvv]

There should be a total of 8 O-rings including the large one. I would check carefully around your work area, they have a tendency of escaping from the plastic bag!!

[PennyDreadfuls]

There should be a total of 8 O-rings including the large one. I would check carefully around your work area, they have a tendency of escaping from the plastic bag!!

Damn. There was definitely only 6 in there. I cut the bags open at my little work area and was certain none escaped... I'll have to check again...

[PennyDreadfuls]

yeah, thats WAY too big.
IIWM, id take my jet and carbs down to the local auto store.  they usually have a good selection of metric buna or viton orings behind the counter in a case.  you might find one that fits for $.50    it should be a much tighter fit than whats on there now.  Just a finger smear of motor oil on the o-ring before you push it in to prevent ripping.

What sort of auto store would carry that? We tend to only have the "big-box" places around here. 

I suppose then I have to figure out what the fit is suppose to be. I'm assuming it's simply a snug fit more that a "press-in" situation that I'm looking at here with the wrong gasket...

[harisuluv]

If you can't find it on the floor at work I can send you what you need.

[Black 750K8]

If you can't find it on the floor at work I can send you what you need.

Does not get any better than that.

[TwoTired]

Here is what my kits have.
 The big thick one in the upper right is actually two rings.

[PennyDreadfuls]

Here is what my kits have.
 The big thick one in the upper right is actually two rings.

And this one (yellow arrow) looks like the correct gasket for the jet, correct?

[ekpent]

This shows what may be some of the usable gaskets and their size in the 500/550 carbs. May be helpful on a hardware/auto store run.  http://forums.sohc4.net/index.php?topic=110256.msg1247344#msg1247344

[TwoTired]

Here is what my kits have.
 The big thick one in the upper right is actually two rings.

And this one (yellow arrow) looks like the correct gasket for the jet, correct?

Correct.

[PennyDreadfuls]

This shows what may be some of the usable gaskets and their size in the 500/550 carbs. May be helpful on a hardware/auto store run.  http://forums.sohc4.net/index.php?topic=110256.msg1247344#msg1247344

That's super helpful. Thanks!

Re-posting here for posterity's sake:

I was able to order individual o-rings from theoringstore.com and fit all the o-rings as follows

needle jet - 1.5mm x 5mm

main jet - 1.2mm x 3.5mm

bowl drain screw - 2mm x 4mm

float bowl - 2mm x 68mm (really needs 68.5mm though)

fuel feed tee - 2mm x 7mm   hope this helps

[TwoTired]

Don't forget, material choice is just as important a size.  With today's ethanol gas, you are better off with Viton as a material.
Hardware store rubber is fine for household plumbing.  Not so great for carbs.

[PennyDreadfuls]

This shows what may be some of the usable gaskets and their size in the 500/550 carbs. May be helpful on a hardware/auto store run.  http://forums.sohc4.net/index.php?topic=110256.msg1247344#msg1247344

Hmm. I just looked a bit closer at that list:
main jet - 1.2mm x 3.5mm

That would be the thickness (1.2mm) and the OD (3.5mm), correct?

[Deltarider]

You may find this informative.
http://forums.sohc4.net/index.php?topic=90925.msg1017076#msg1017076

[mono]

i got all my o-rings from a Harbor Freight kit for $7.  Had everything I needed, plus extras!

[PennyDreadfuls]

i got all my o-rings from a Harbor Freight kit for $7.  Had everything I needed, plus extras!

Yeah, I looked there, but they don't appear to have anything remotely close to the: main jet - 1.2mm x 3.5mm sizing

[dave500]

find a local diesel injector and pump service place,they have odd ball stuff.

[mono]

i got all my o-rings from a Harbor Freight kit for $7.  Had everything I needed, plus extras!

Yeah, I looked there, but they don't appear to have anything remotely close to the: main jet - 1.2mm x 3.5mm sizing

yeah i looked at the ones in my kit and you're right -- so i must have used the ones from my carb rebuild kit(s).  However, it's still a good o-ring kit to get.  i know i used them for the connector tubes and valve caps/intakes.
http://www.harborfreight.com/397-piece-metric-o-ring-assortment-67580.html