Metering jets and rods for a quadrajet 4MV

[sjujnovich]

I am trying to modify a quadrajet from a 4.3L V6 mercruiser engine (part number 17084516 2001) to suit a 5.7 mercruiser engine (Ie 350 chev from the mid 80's) .

I believe this can be done. (Same carb but different rods/jets/hanger).

Sorry I don't have a serial number for the engine.

Does anyone know what changes are needed to the primary metering jets and rods and the secondary metering rods and hangers?

If anyone knows the specified numbers (stamped or part numbers) for these parts I would love to know.

 

[lime4x4]

Re: Metering jets and rods for a quadrajet 4MV

this site might be able to help u atleast with the parts
http://www.carburetion.com/quadrajet.asp

 

[sjujnovich]

Re: Metering jets and rods for a quadrajet 4MV

Thanks, good site for parts ordering.

But I really need to know which parts to order.

Anyone have a specification / technical data sheet for the 4MV quadrajet for a mid 1980's mercruiser 350 engine?? Or part numbers for the jets/metering rods/hangers required??

Must be someone out there with some mercruiser quadrajet expertise.

Any help really appreciated.

 

[lime4x4]

Re: Metering jets and rods for a quadrajet 4MV

did u download the manual for a 350 engine from the adult only section? I beleive they give u the specs

 

[dan t.]

Re: Metering jets and rods for a quadrajet 4MV

chev 350 volvo penta 260 HP Q-jet #17059298
pri jet 69
pri mr 40
sec rod cj
sec hanger k

Q-jet #17059298 merc 260 HP
pri jet 69
pri mr 40b
sec rodcj
sec hanger j

Q-jet merc 350 mag# 17080562
pri jet 69
pri mr 35
sec mr ch
sec hanger g hope this helps

 

[sjujnovich]

Re: Metering jets and rods for a quadrajet 4MV

Thanks so much for the excellent advice lime4X4 and dan t. Exactly what I wanted, the info will help me heaps.

I have had lots of trouble trying to download the manuals for the 5.7 mercruier motor. I think it is partly because I am in Australia and need to use a web proxy to even get access iboats forum as we seen to be barred from the site - ? related internet security issue or something like that.

 

[kljr99]

Re: Metering jets and rods for a quadrajet 4MV

metering rods make all the differance in performance if you modify your engine change the rods. even just open exhaust will make a differance go a little richer the rods are cheap.
here are some good links
mercruiser oem service bulletin
http://www.boatfix.com/merc/bullet/93/93_15.pdf
high altitude rods will run leaner also lowering your float level a little. This will help you a lot to run leaner at altitude. I was a machanic in the 80s in summit county colo. 9000 ft,
This page list the rods
http://www.hioutput.com/tech/qjetrod.html
the smaller the tip the richer you will run
the 60 and 70 degree numbers are importent if you bog out in mid range as the secondarys are opening boging can mean your running to rich also. the air valve adjustment can help the S.B pic is wrong a= is the choke not the air valve the air valve is the choke looking plate for the secondary and the spring is adjusted with a small allen wrench/torx under the air horn.
increase the spring tension for later opening if you are bogging down looking for around 2800 to 3500 rpm to give a good even accelaration. It is not suppose to be a qudrabog its a qudrajet.
good tuning paper
arapaho.nsuok.edu/~leeaq/docs/QJet_Tuning_Paper.doc