7040204

[Terry M.]

Re: 7040204

Patrick,
What the heck is a base basket? [b]And what is that cylindrical object between the linkage and the carburetor?[b]
It appears on my friend's carburetor that when the spring is properly attached it will pull that part up and clear the bolt. But the linkage looks nothing like my '70 LS-5's. Or any others I have seen.

Thanks,
Scott

That cylindrical object is called a dash pot and should be on all 1970 Rochester carburetors with manual transmission. Its purpose is to slow down the closure of the throttle plates to prevent the sudden shut off of air to the engine on throttle release.

[D S.]

Re: 7040204

Patrick and Scott------


The GM #3967470 gasket is a bit thicker than the one shown but likely not enough thicker to raise this carburetor enough for the lever to clear.

In this case, I think that this carburetor has been at some point fitted with a carburetor throttle body assembly that's not correct for this carburetor part number. As with most other commercially rebuilt parts, the numbers on the carb may mean nothing. A rebuilder may "mix-and-match" parts to build up whatever carburetor they wish.

As far as the "cylindrical object" goes, if Scott's speaking of the device seen to the left of the carburetor and attached to the right side of the intake manifold, that is the transmission controlled spark (TCS) solenoid. It interrupts vacuum
advance under certain engine operating conditions.

No, I think Patrick kind of explained what that device is. I have the TCS. This object is mounted on the left of the carburetor just behind the lever plate and juts out. Why would I not have that and do I really need it?

[Terry M.]

Re: 7040204

No, I think Patrick kind of explained what that device is. I have the TCS. This object is mounted on the left of the carburetor just behind the lever plate and juts out. Why would I not have that and do I really need it?

I am pretty sure with the auto transmission you don't need it. The free-wheeling construction of the TH 400 negates the need for the dash pot.

[D S.]

Re: 7040204

I am pretty sure with the auto transmission you don't need it. The free-wheeling construction of the TH 400 negates the need for the dash pot.

Thanks, Terry. Will you be able to attend the NCRS event in Frisco, Texas?

[Terry M.]

Re: 7040204

Thanks, Terry. Will you be able to attend the NCRS event in Frisco, Texas?

I have hotel reservations, but the other Fall Regional, in Sacramento, is in the same month. Getting off work for two meets in the same month is hard for us retired folks.

[D S.]

Re: 7040204

I have hotel reservations, but the other Fall Regional, in Sacramento, is in the same month. Getting off work for two meets in the same month is hard for us retired folks.

I know what you mean. Being retired, too, I have little time to do anything else for all the nothing I do.
If you do make the Frisco show I look forward to seeing you again. I live just 45 minutes from Frisco. It has all of three ZIP codes, one just recently added.

[Tom L.]

Re: 7040204

Not sure if this will help but I saw this this morning.

http://cgi.ebay.com/ebaymotors/Corvette-1970-Rochester-7040204-Chevelle-402-454-396-/330565520553?pt=Vintage_Car_Truck_Parts_Accessories&hash=item4cf73d8ca9

(BTW, I have nothing to do with the listing)

[D S.]

Re: 7040204

Not sure if this will help but I saw this this morning.

http://cgi.ebay.com/ebaymotors/Corvette-1970-Rochester-7040204-Chevelle-402-454-396-/330565520553?pt=Vintage_Car_Truck_Parts_Accessories&hash=item4cf73d8ca9

(BTW, I have nothing to do with the listing)

Thanks, Lynn. I didn't see that one yesterday morning but I found four in the Completed section. It looks like one my friend should have purchased as his engine is a June built one. It has the same stuff mine has and looks just like my January 1970 built one.