Can you tell a marine cabr from an auto one by looking at it?

[LAC_STS]

I got the carb off of my old engine and I found out that its a Weber but googleing the numbers on it doesnt turn up anything.


I have an Edelbrock 1409 on my new engine and this carb looks pretty close to it.

Question is the vent tubes that everyone talks about that on an auto carb vent excess fuel out of the carb, and on a marine carb dump the fuel back in to the carb as to not cause an explosion issue; where are these tubes?

On an auto carb are they the tubes that stick up through the air horn next to the primaries right on the outside of where the flame arrestor / air filter goes?

And is it correct that an easy way to tell the difference is that no marine carbs have vacuum ports on the front of it?

I can tell where the vacuum ports would be on my 1409. There is none but I can tell where they would be on the front. But on the Weber carb there are 3 vacuum ports on the front. I assume for power breaks and vacuum advance.

 

[EddiePetty]

Re: Can you tell a marine cabr from an auto one by looking at it?

I got the carb off of my old engine and I found out that its a Weber but googleing the numbers on it doesnt turn up anything.


I have an Edelbrock 1409 on my new engine and this carb looks pretty close to it.

Question is the vent tubes that everyone talks about that on an auto carb vent excess fuel out of the carb, and on a marine carb dump the fuel back in to the carb as to not cause an explosion issue; where are these tubes?

On an auto carb are they the tubes that stick up through the air horn next to the primaries right on the outside of where the flame arrestor / air filter goes?

And is it correct that an easy way to tell the difference is that no marine carbs have vacuum ports on the front of it?

I can tell where the vacuum ports would be on my 1409. There is none but I can tell where they would be on the front. But on the Weber carb there are 3 vacuum ports on the front. I assume for power breaks and vacuum advance.

.....some marine carbs have a nipple in the upper area of the air horn to accept the tell-tale tube from the fuel pump: some do not and the tell-tale attaches to the flame arrester.
Marine carbs have no vacuum ports.
Marine carbs have no external vents.
Marine carbs have no steps nor ramps on the 'fast idle cam'.

The brighter bulbs on the string will be along soon to shine more light on the subject.

 

[Bondo]

Re: Can you tell a marine cabr from an auto one by looking at it?

Marine carbs have no vacuum ports.

Ayuh,... Not quite True,...
The Merc/ Weber carbs like LS probably has, do have vacuum ports,... Atleast some, as 1 of mine uses it for the choke pull-off...

Btw,... Those Merc/ Webers don't just look alittle like the Edlebrocks,... They've virtually the Same...
Even the parts, 'n pieces interchange....
Once I figured that out, it made Tuning the Merc/ Webers Much cheaper,+ Much Easier...
Especially when armed with This little tidbit of Info,...

 

[LAC_STS]

Re: Can you tell a marine cabr from an auto one by looking at it?

Ayuh,... Not quite True,...
The Merc/ Weber carbs like LS probably has, do have vacuum ports,... Atleast some, as 1 of mine uses it for the choke pull-off...

Btw,... Those Merc/ Webers don't just look alittle like the Edlebrocks,... They've virtually the Same...
Even the parts, 'n pieces interchange....
Once I figured that out, it made Tuning the Merc/ Webers Much cheaper,+ Much Easier...
Especially when armed with This little tidbit of Info,...

I like that manual too. I've saw you link to it a lot in the past couple days.


The little brass tubes that i'm talking about. Are those vent tubes? If you take the air horn off you can see that they stick out of the top of the primary boosters.

They stick up through the air horn right on the outside of the flange that the flame arrestor would go on.

are these the vent tubes that should not be there on a marine carb?

I have looked and looked and looked and cannot find any info on this carb. I even looked on Webers website and looked at Webers for sale and I cant even find out that looks like this one.

The numbers on it are

9755S 0731 On front bottom left
8867 on top

But I guess it dont matter either way if its an auto carb.

 

[Bondo]

Re: Can you tell a marine cabr from an auto one by looking at it?

I have looked and looked and looked and cannot find any info on this carb. I even looked on Webers website and looked at Webers for sale and I cant even find out that looks like this one.

Ayuh,... Just look in any late model Mercruiser manual for any 4bbl. equiped motors...
V6, V8, SBC, BBC...
Merc parts lookups will list it by #s,...

If the bore are identically sized, it's a 750cfm,...
If the primaries are slightly smaller, it's a 600/650cfm...

 

[LAC_STS]

Re: Can you tell a marine cabr from an auto one by looking at it?

If the bores are the same size as my 1409? The 1409 is 600 CFM though right?