mercruiser rochester quadrajet carburetor

[bluetwoplustwo]

hi all, i have a mercruiser 5.0 228 v8 year is 1982 with the rochester quadrajet carburetor, the lower part off carb at the front there are 3 vacuum/vent pipe fittings, can anyone help as to witch pipe goes were ? (one vacuum on side of carb,one on distributor) cant seem to find anything in clyner/seloc telling me were they go to. thanks

 

[achris]

Re: mercruiser rochester quadrajet carburetor

The reason you can't find anything in the manual is because you appear to have a automotive carb on the engine. Suggest you find a marine carb to replace it.<br /><br />Chris.............

 

[Bondo]

Re: mercruiser rochester quadrajet carburetor

Ayuh,..........<br />Looks like it's an Automotive Distributor Also......<br />Marine units Don't Use Vacuum Advance.........<br /><br />Better Check the Fuel Pump, Starter,+ Alt. Also.....<br />Automotive Parts make boats go BOOM.........

 

[bluetwoplustwo]

Re: mercruiser rochester quadrajet carburetor

thanks for replys , but exploded picture in clymer/selco shows them but not were they go, and the distributor looks the same as the thunderdolt breakerless ignition system pictured in the books,!! thanks ?

 

[bluetwoplustwo]

Re: mercruiser rochester quadrajet carburetor

have had a look and the carburetor is the same as the picture in the seloc mercruiser 1964-91 repair manual on page 4-42 , number 50(vacuum break control assembly)would like to know were the vacuum hose goes to, page 4-44 picture 7 there are 3 vent/vacuum/breather? fittings would like to know were they go please ,also the distriutor page 5-3 top right picture is the same thunderbolt iv ignition with sensor and sensor wheel instead of points, mine has sae j1171 marine on it!!! any help please, thanks

 

[achris]

Re: mercruiser rochester quadrajet carburetor

B2+2,<br /><br />I have never put much faith in manuals not from the manufacturer. All the reference books I use when posting on this site are Merc Genuine manuals. The books and pictures I am looking at have only one external port, and that's for the dashpot on the side of the carb. <br /><br />Just because there's a label saying 'Marine' doesn't mean that the previous repairer didn't take it off the original carb and put it on the new one. There's a considerable difference in price and he may have just done the job on the cheap.<br /><br />Can you post pictures of the ports in question?<br /><br />Chris.

 

[cc lancer]

Re: mercruiser rochester quadrajet carburetor

Look at the picture on 4-43 number 2 it shows the vacuum hose hook up.<br />The one directly to the right is a fuel return to the fuel pump.<br />The one directly beside the large fuel inlet is a breather-out that would go to the valve cover.<br />I'm lost on the distributor question, the tube on the back of the distributor is an air vent.<br />Don't bet the bank on the manuals, they are generic at best.

 

[Bondo]

Re: mercruiser rochester quadrajet carburetor

Seloc is Right Up there with Charmin,.....<br /><br />Except,.........<br /><br />Charmin uses Better Paper,.......<br /><br />And,..... Has Better Information..........

 

[qystan]

Re: mercruiser rochester quadrajet carburetor

2+2<br /><br />On my carb there are only 2 vents.<br /><br />1. to the secondary air valve diaphragm assy<br />2. to the fuel pump<br /><br />You mentioned "lower part off carb at the front there are 3 vacuum/vent pipe fittings".<br /><br />These vents are on the mid-section of the carb (main body) not the lower throttle valve assy section.

 

[olbuddyjack]

Re: mercruiser rochester quadrajet carburetor

I love bondo's non-biased opinions...

 

[bluetwoplustwo]

Re: mercruiser rochester quadrajet carburetor

hi all, thanks for all the replys, started thinking what use is a boat i cant use,or what more is she going to cost to get in the water! hope to spend some time sorting out some things on her this weekend, (sorry cant take/upload pictures) thanks again

 

[bluetwoplustwo]

Re: mercruiser rochester quadrajet carburetor

hi all, can i just say feel like a prat! she is same as qystan (2 vents)2 off cut bits off vent pipe put over mixture screws heads ,and i thought they were vent pipes and looking for were they should go, opps sorry ?

 

[achris]

Re: mercruiser rochester quadrajet carburetor

ROTFLMAO!<br /><br />P.S. Have fun.....

 

[Manipulator]

Re: mercruiser rochester quadrajet carburetor

Wow, that was a good one. Don't worry, I probably have the exact same carburetor as you or pretty close to it. I have a Chevy 350 with a Rochester Quadrajet and my boat is an 83. Anyway, I just got done rebuilding it and accidentally put the rod that holds the air cleaner/flame arrestor down the float bowl vent and drove a hole right through the float! Had to take it off the engine and take it all apart again, clean it out and find a new float. Finding a float was a nightmare as the float is much larger than the same carb that goes on automobiles. I went to about 6 different auto parts stores and none were right. I then went to AutoZone and a guy went through about 20 boxes of floats and found it. So don't feel bad I'm new to boating too. My carb also only has one vacuum port and it goes to the diaphragm that holds the secondaries shut until vacuum drops and allows them to open (not sure what it is called). Like many have said here, marine distributor has no vacuum advance, which confused me too.

 

[Bondo]

Re: mercruiser rochester quadrajet carburetor

I Wish All of EveryBodies Problems were so Easy to Fix....... <br /><br />I've been Turning Wrenches All My Life......<br /><br />I've done Alot Worse,.... Many Times......... But, I'm Not Going to Tell You Here.............