Doug Redinger
Seaman
- Joined
- May 22, 2005
- Messages
- 73
I have a 1988 mercruiser 165 that came with the mercarb 2 barrel carburetor. Last summer I installed the 4 barrel manifold and 4 barrel quadrajet ( part # 170-88352) which I purchased off of ebay. Both were in very good condition, but I cleaned them up and installed a kit in the carburetor just to be sure everything was clean and functioning properly. Well I never got a chance to run the boat before winter came and so this spring I finally took the boat out and guess what? The motor idles well but it has a terrible off-idle stumble and lacks any real top end ( 3800 or so max rpm when it should be 4400-4800 rpm). It ran better with the 2-barrel mercarb by far. I realize that quadrajets are a little bit of a pain to tune but want to try to get it dialed in anyway. I did notice that the carb was missing the the secondary air-valve adjustment screw and spring, although allen-head set screw is still on carb. It has # 65 primary jets on it now, but I don't know what it has for primary metering rods as I forgot to look or take note when I rebuilt it last summer. I realize that the secondary jets are not removable.
My question is this : does anyone have the factory specs for this motor and carb combination? Primary jet size? Metering rods specs for both primaries and secondaries? How many turns on secondary air-valve spring screw----marine rebuild kit specified 3/8 turn on screw---, but want to be sure. Which power piston springs should be used, bought edelbrock power-piston spring kit # 1994 which came with 4 different springs. How many inches of vacuum below manifold vacuum do I want for the power-piston spring? Any information would be greatly appreciated.
P.S. Lund Magnum 2100 run mainly at 4000 ft elevation or higher on Montana's mountain lakes.
Thanks in advance to all responders
Doug
My question is this : does anyone have the factory specs for this motor and carb combination? Primary jet size? Metering rods specs for both primaries and secondaries? How many turns on secondary air-valve spring screw----marine rebuild kit specified 3/8 turn on screw---, but want to be sure. Which power piston springs should be used, bought edelbrock power-piston spring kit # 1994 which came with 4 different springs. How many inches of vacuum below manifold vacuum do I want for the power-piston spring? Any information would be greatly appreciated.
P.S. Lund Magnum 2100 run mainly at 4000 ft elevation or higher on Montana's mountain lakes.
Thanks in advance to all responders
Doug
