Rochester 2GC info - Page 5

NORMAN BARNARD · 09-30-2015, 07:14 PM

T ketels.....that's the one!!!!!! They work "super" with a little prep
work...... Not like the work that has to be performed on the 50 plus year old rochester (if you can find a good one)....

Charlie A · 09-30-2015, 09:43 PM

Quote:

Originally Posted by T Ketels

Here's a couple of pictures of the marine 2G - it measures 1.375 but it has sleeves in each bore. I've never built one to try yet - one of these days.

Tim

Click the bar at the top of the picture for full size.

Mark Yacavone · 09-30-2015, 10:24 PM

Looks like the throttle shaft is machined away.They won't be approving that!

NORMAN BARNARD · 09-30-2015, 10:26 PM

Tim, can you please verify that the carb's in the pic's truly have "sleeves" and also send me the carb. Numbers off the bowl's
please. You may have to scrape off the factory painting to reveal them..

I made a copy of the picture looking down the top for reference
as i've never seen sleeves in stock marine carb's, then went to the shop where we have two being built...look'd the same, perhaps it's a reflection or a shadow from the camera.

Just curious, and making sure i haven't missed something along the way...... Thank you for your time......norm

NORMAN BARNARD · 09-30-2015, 10:34 PM

Mark, if your refering to the throttle shaft where it exit's the passenger side of the carb., marine carb's do not have a thru hole like the rochesters. It's a blind hole in the casting to keep out the salt water and a occasional spilled adult beverage !!!!!

Rochester's we pressed in a small soft plug for the above.....

OOPS, I JUST SAW WHAT YOU WERE TALKING ABOUT, MARINE CARB. SHAFTS ARE MOUNTED UPSAIDE DOWN (FLAT SURFACE UP, MAKING IT LOOK LIKE IT'S BEEN INTENTIONALLY MACHINED)
THROTTLE PLATES ARE SANDWICHED BETWEEN THE SHAFT'S UPPER AND LOWER HALF, LIKE THE ROCHESTER AND RETAINED WITH BRASS SCREWS LIKE THE ROCHESTER.......

T Ketels · 10-01-2015, 07:20 AM

Here are a few more pictures of the marine 2G. You are correct, the throttle shaft is slabbed which would definitely not pass tech!

NORMAN BARNARD · 10-01-2015, 03:05 PM

Ok, here we go on the two marine carb'.....in question.

Photo #1with bowl marking of 06082a-1 s/b "8"o682a-1 (probably still covered by paint). Any way, this p/n has been superceded by 3310-807312-1, so i'm told....

Photo #2 shows the bottom of the venturi hsg. And yes this early style carb. Originally came with venturi inserts and a detachable baseplate off a rochester carb. M/marine pluged the
two original idle screw holes, then tap'd the front middle vac. Hole for the "one" idle application. Then machined the base plate idle channels to intercept with the original channel that feeds the idle circuit and the transission slot. Sorry, i was unable to find the venturi spec's, maybe the originator of the post could measure and report.

Photo #3 shows the roch. Baseplate that attaches to the venti
hsg. With "3" screws. Shaft is like the roch. Flat is on the bottom, radius is on the top countersunk for the attaching screws.

Remember this is the "old style marine" not the one that is presently available and dimensionally meets the published spec.

NORMAN BARNARD · 10-02-2015, 04:06 PM

Dwight southerland, pm sent......

outlaw · 10-09-2015, 10:40 PM

I have a mercury marine 2gc that's 1 3/8 casting no sleeves no bore marks. Number 7044185

NORMAN BARNARD · 10-10-2015, 11:24 AM

The 6th digit of an 8 indicates it's a non gm part. It's truly a merc. Marine carb. Installed on a 4.9 liter motor. Venturi should be large bore (1.375) and 2 idle screws under the float bowl

check the booster leg to see if it has the good booster #38864,
if it does, then it's a good start for maybe a stocker.

09-30-2015, 07:14 PM	#41
NORMAN BARNARD Member Join Date: Mar 2006 Location: EL PASO, TEXAS Posts: 156 Likes: 0 Liked 2 Times in 2 Posts	Re: Rochester 2GC info T ketels.....that's the one!!!!!! They work "super" with a little prep work...... Not like the work that has to be performed on the 50 plus year old rochester (if you can find a good one)....

09-30-2015, 10:24 PM	#43
Mark Yacavone Veteran Member Join Date: Mar 2002 Location: Miles From Nowhere Posts: 7,414 Likes: 2,579 Liked 4,447 Times in 1,693 Posts	Re: Rochester 2GC info Looks like the throttle shaft is machined away.They won't be approving that! __________________ We are lucky we don't get as much Government as we pay for..... Will Rogers

09-30-2015, 10:26 PM	#44
NORMAN BARNARD Member Join Date: Mar 2006 Location: EL PASO, TEXAS Posts: 156 Likes: 0 Liked 2 Times in 2 Posts	Re: Rochester 2GC info Tim, can you please verify that the carb's in the pic's truly have "sleeves" and also send me the carb. Numbers off the bowl's please. You may have to scrape off the factory painting to reveal them.. I made a copy of the picture looking down the top for reference as i've never seen sleeves in stock marine carb's, then went to the shop where we have two being built...look'd the same, perhaps it's a reflection or a shadow from the camera. Just curious, and making sure i haven't missed something along the way...... Thank you for your time......norm

09-30-2015, 10:34 PM	#45
NORMAN BARNARD Member Join Date: Mar 2006 Location: EL PASO, TEXAS Posts: 156 Likes: 0 Liked 2 Times in 2 Posts	Re: Rochester 2GC info Mark, if your refering to the throttle shaft where it exit's the passenger side of the carb., marine carb's do not have a thru hole like the rochesters. It's a blind hole in the casting to keep out the salt water and a occasional spilled adult beverage !!!!! Rochester's we pressed in a small soft plug for the above..... OOPS, I JUST SAW WHAT YOU WERE TALKING ABOUT, MARINE CARB. SHAFTS ARE MOUNTED UPSAIDE DOWN (FLAT SURFACE UP, MAKING IT LOOK LIKE IT'S BEEN INTENTIONALLY MACHINED) THROTTLE PLATES ARE SANDWICHED BETWEEN THE SHAFT'S UPPER AND LOWER HALF, LIKE THE ROCHESTER AND RETAINED WITH BRASS SCREWS LIKE THE ROCHESTER....... Last edited by NORMAN BARNARD; 09-30-2015 at 10:43 PM. Reason: CLARIFICATION

10-01-2015, 07:20 AM	#46
T Ketels Junior Member Join Date: Jul 2005 Location: Dyersville, Iowa Posts: 52 Likes: 0 Liked 0 Times in 0 Posts	Re: Rochester 2GC info Here are a few more pictures of the marine 2G. You are correct, the throttle shaft is slabbed which would definitely not pass tech! Attached Thumbnails __________________ SS/MA 5017

10-01-2015, 03:05 PM	#47
NORMAN BARNARD Member Join Date: Mar 2006 Location: EL PASO, TEXAS Posts: 156 Likes: 0 Liked 2 Times in 2 Posts	Re: Rochester 2GC info Ok, here we go on the two marine carb'.....in question. Photo #1with bowl marking of 06082a-1 s/b "8"o682a-1 (probably still covered by paint). Any way, this p/n has been superceded by 3310-807312-1, so i'm told.... Photo #2 shows the bottom of the venturi hsg. And yes this early style carb. Originally came with venturi inserts and a detachable baseplate off a rochester carb. M/marine pluged the two original idle screw holes, then tap'd the front middle vac. Hole for the "one" idle application. Then machined the base plate idle channels to intercept with the original channel that feeds the idle circuit and the transission slot. Sorry, i was unable to find the venturi spec's, maybe the originator of the post could measure and report. Photo #3 shows the roch. Baseplate that attaches to the venti hsg. With "3" screws. Shaft is like the roch. Flat is on the bottom, radius is on the top countersunk for the attaching screws. Remember this is the "old style marine" not the one that is presently available and dimensionally meets the published spec.

10-02-2015, 04:06 PM	#48
NORMAN BARNARD Member Join Date: Mar 2006 Location: EL PASO, TEXAS Posts: 156 Likes: 0 Liked 2 Times in 2 Posts	Re: Rochester 2GC info Dwight southerland, pm sent......

10-09-2015, 10:40 PM	#49
outlaw Junior Member Join Date: Aug 2008 Posts: 78 Likes: 52 Liked 58 Times in 33 Posts	Re: Rochester 2GC info I have a mercury marine 2gc that's 1 3/8 casting no sleeves no bore marks. Number 7044185

10-10-2015, 11:24 AM	#50
NORMAN BARNARD Member Join Date: Mar 2006 Location: EL PASO, TEXAS Posts: 156 Likes: 0 Liked 2 Times in 2 Posts	Re: Rochester 2GC info The 6th digit of an 8 indicates it's a non gm part. It's truly a merc. Marine carb. Installed on a 4.9 liter motor. Venturi should be large bore (1.375) and 2 idle screws under the float bowl check the booster leg to see if it has the good booster #38864, if it does, then it's a good start for maybe a stocker.