Zenith Carb Swap

[jmoylan69]

anyone ever swap out a zenith 28 series carb for say a carter or holley etc on the M35 REO's?

Im curious what carb options there are or are you limited to the Zenith's?

 

[Barrman]

I thought you just got your Zenith figured out?

Both of my Gassers have the stock Holley on them still.

Several members have also swapped in civy versions of the Gold Comet engine parts to get better performance.

 

[hndrsonj]

Sam Weiners has the Holleys brand new.

 

[jmoylan69]

Barrman, i did and do. but what i got is it seems like the fuel pump is over supplying the carb. I rebuilt the fuel pump with a new kit, and checked the float height and if the float was sinking and sticking. im good there! the pump is the original mechanical pump with new check valves and seals. the zenith manual for 28ada10 calls for a float level of 1.5 inches.

you think im missing something perhaps?

and HNDRSONJ, thanks for the info i'll check those out too!!!

 

[jmoylan69]

im wondering if i have the wrong manual, my carb number is 13894 and the manual i got was for the zenith 28D series. isnt that correct?

 

[Barrman]

My rebuilt Holley to spec bubbled over after idling at least 10 minutes. I kept adjusting the float down just a hair at a time until it would idle all day long without getting the burbles. Still had great WOT application at any rpm. I have no clue what I finally ended up at, just that it works.

I know that really doesn't help you, but with 60 years of chemical changes to the fuel. What worked in 1951 might not be all that great today. Besides, it isn't like you are going to go from 4.9 mpg all the way up to 5.3 mpg or something drastic like that. Just make it so you like the way it runs and leave it alone.

 

[jmoylan69]

OK barrman, believe it or not that does help me out. I was thinking these things had to be adjusted to the gnats @$$. my thinking was along the same lines. good to know and thanks again.

joe

 

[Barrman]

Glad to help.

 

[JasonS]

The Holley economaster is easy to attach and works MUCH better than the stock carb.

 

[jmoylan69]

hey jason what are those running these days? can i pick em up cheap or are they 400 dollar carbs?

i've always had this thing about spending a ton of money on carbs. and i personally have never seen an 885 FFG holley

 

[jmoylan69]

and that setup you have looks good to me. but I know the full value of oil bath filters and would prefer to keep mine. they really pull the dirt out

 

[JasonS]

and that setup you have looks good to me. but I know the full value of oil bath filters and would prefer to keep mine. they really pull the dirt out

You will be fine with a good paper element. You could probably even use the multifuel air filter.

 

[JasonS]

hey jason what are those running these days? can i pick em up cheap or are they 400 dollar carbs?

i've always had this thing about spending a ton of money on carbs. and i personally have never seen an 885 FFG holley

I spent ~$50 to $70 each off of ebay. They are significantly improved from the simple holley and zenith. Specifically, they have better (economaster) boosters, two stage power valve, and reverse idle. Much better driveability.

 

[rainbow]

Put a 327 or 350 chevy carburetor on your gas m35 and it will run great. They work well on the GMC M series also.