I need pictures of rochester carb for a 1985 454 chevy. These pictures need to show me where all the lines from the carb go to. We are trying to put motor back together that we did not take apart so we don't have a clue where these vacuum lines, springs and all that good stuff hook up to.

Check your mail. They should all be there.

I gottem.

Jeff,
Would you send those pics to me to. I am not sure that mine is hooked up correctly.
Thanks

Jeff or Mary... any chance you could just post them here?

Please keep in mind I haven't gotten around to this kind of housekeeping yet..

The following Picture and Diagram I received from Doug Bywaters, a member of Barthmobile.

Ours is really hard to start when the engine is cold. Thanks for the pics. They will definitely help me to change the current setup.

quote:

Originally posted by jsloan:

OH OH!

Two things in the last picture make me nervous.

1. There should be no rubber fuel line anywhere up front except from the frame to the fuel pump. Heat, age and rubbing can cause a fire. If there are rubber fuel lines, a little safety can be bought by using (and frequently inspecting) fuel injection hose. It lasts a little longer.

2. Worm drive clamps do not actually loosen, but the hose shrinks with age and heat, allowing a leak. I don't like them anywhere. Except the constant-tension ones that use a coil spring or Belleville washers to compensate for shrinkage. I am not sure they are available in fuel hose sizes. Even the much-vaunted double-ear Oetiker clamps have very limited ability to make up for shrinking hoses in a high heat environment.

It is worth noting that OEM filter hoses use a flat version of the Corbin design (my favorite). All my fuel line connections have two 90 degree-staggered Corbin clamps.

This may sound a little fussy, but so many gasser fires are fuel leaks.

While wearing my Fireman hat, another cause of gasser fires is an overheated trans boiling fluid up and out the filler tube onto hot exhaust. Install a trans temp gauge and evaluate the need for a cooler. Synthetic trans fluid has a higher flash point and makes your trans run cooler.

quote:

Originally posted by Tommy/MS:
Ours is really hard to start when the engine is cold.

Is it hard to start cold when it has sat for weeks?

Is it hard to start cold when it has sat for a day?

Does the accelerator pump work well?

Does pumping the throttle half a dozen times
before cranking make any difference?

Does the choke do its thing? Is it free? The rivets on the choke housing can be drilled out and replaced with screws for adjustment to compensate for the aging of the bimetallic coil inside.

Once it lights off, does it run OK?

Is there fuel in the bowl after it has sat? This can be checked by looking down the throat as the throttle is pumped.

Q jets like to leak when really hot from a soft plug on the underside. This can cause hard starting, as the engine must be cranked to fill the float bowl.

This is also a potential fire hazard. Check for fuel residue under the carb. The area should be cleaned well and a couple of paper towels packed under the carb. After a hot run, any carb leak will show up when the paper towels are inspected. Or a good sniff and visual test after a hot shutdown is good, too.

How would a heat riser valve fit into this equation?
Tere

Mary,
Here are my pics before I removed the carb.
















Don't know what happened here.


Tere

Suggestion... After you get your coach started, I want you to spray carb cleaner around the base of the carb and around anything that might be sucking in a vacuum. Spray it around the intake manifold gaskets too. If the RPMs rise, then you have a vacuum leak there.

quote:

Originally posted by Jim and Tere:
How would a heat riser valve fit into this equation?
Tere

Not for hard starting. The heat riser valve blocks one exhaust bank, forcing exhaust into a hollow area under the carb and over to the other side. This improves cold weather heat atomization shortly after engine start. Maybe a minute or so. As soon as the engine warms up, the heat riser is open, and there is no forced diversion of exhaust gas through the manifold passage. It does, however, stay open, so hot exhaust still heats it up, and supplies exhaust to your carb through the EGR valve for pollution legality.

Warning: illegal information follows: Unless you do cold winter starts a lot, the heat riser can be left open. If you seldom do deep winter starts, or are willing to put up with a slightly balky warm up, and don't care about smog legality, the heat riser passages can be blocked at the intake gasket surface. The carb will run cooler, with better performance and economy, and the oil will not splash up against the hot heat riser chamber. This means cooler oil and less coke.

quote:

Originally posted by Jim and Tere:



Don't know what happened here.


Tere

It's bad on Photobucket, as well. Perhaps you should reload it to Photobucket.