454 thunderbolt 4 timing

TBarCYa

Senior Chief Petty Officer
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Apr 13, 2005
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781
For some reason I thought it was the Rochester... Looking at pics online it's the Weber.

The carb is brand new. I'll double-check the filter. In the meantime, does anyone have any pics of the secondary air valve adjustment?
 

TBarCYa

Senior Chief Petty Officer
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Apr 13, 2005
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That doc doesn't mention anything about the secondary air valve adjustment... So maybe this carb doesn't have one? Oh, and it's a rebuilt Weber.
 

achris

More fish than mountain goat
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May 19, 2004
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27,468
One of the beauties of the Weber is so few adjustments. There is no adjustment of the secondaries. The throttle plates are on a mechanical linkage and the air valves have a counterweight... The only adjustments are float level and choke plate pull down...(and idle speed and mixture)..

Chris...
 

TBarCYa

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Apr 13, 2005
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Still having problems getting her to run right but I'm closer to finding the problem... It's in the carburetor.

This morning I dumped the fuel filter and it was 2/3 water and not clean water. I didn't replace the filter after pumping gas and water out of the tank which likely explains the water in the filter. I replaced the filter today and the hose from the tank and didn't see any improvement so I started looking at the carb figuring the base gasket or something was bad but no luck .

I pulled the carb and took it home and took it apart to find dirt in the carb. Again.

So I have a rebuild kit on order but I can't figure out how the dirt got into the float bowls. There's a water separating filter in place (that was full of water) and the screens in the carb, above the needles, were relatively clean compared to the dirt in the bowls.

I'm installing a see thru filter in the hose so hopefully it'll catch any dirt coming from the tank and I'll be able to keep an eye on it. I just don't know if this is enough. I do know that there's no screen on the pickup in the tank.

Any suggestions what else I can do besides replacing the existing filter and installing a new one? I could possibly have the tank pumped out again and flushed.
 

alldodge

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Mar 8, 2009
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If you have water in the gas its not going to run
If all the water is gone, and you have a clean regular filter your good. No need for inline clear filter, and it not a good idea to use one, dangerous
 

TBarCYa

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I have a new filter but how did the dirt get past the old one? Does it bypass if it gets too dirty or if it's full of water? Why would an inline filter be dangerous?
 

alldodge

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Inline filters are not USCG approved, and if their glass it can break, and if plastic they can melt. Only ones allowed are 100% metal. If anything happened and one was used, then the installer can be in a legal issue
 

aimlow

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Nov 7, 2018
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If you have water in the gas its not going to run
If all the water is gone, and you have a clean regular filter your good. No need for inline clear filter, and it not a good idea to use one, dangerous

NEVER! use a glass or plastic filter in an enclosed bilge. What kind of fuel line do you have? Also, if you have water in the filter, there's water in the carb also. A common problem is the o-ring where the fuel fill on the deck is.
 

TBarCYa

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Apr 13, 2005
Messages
781
The fuel line is 3/8" marine fuel line. Nothing special there. I know how the water got into the tank, what I can't figure out is how the dirt got past the filter and into the carb.
 
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