Main Jet size for carb 7043183?

[YOBE]

Hi,

I have been reading the service manual quite in detail and states that for my setup: Mercruiser 165HP 6cyl 70's it should have the carb 7043183. Engine serial nr is 4506302.

But I would like to verify if the current installed 2 main jets have the correct size.
In the service manual I dont find any reference to this.

Does anyone know where I could find the spec's for the original size of the 2 jets in my setup?

Thanks

 

[YOBE]

Currently I have 2 jets of 0.049 inch. But without finding more details, the info I can find is that this is probably too low.

 

[alldodge]

It's a Rochester carb jet number 1397-3827 but don't know the size

https://www.perfprotech.com/mercury.../model/24554328245614/document/24554340780108

 

[Scott06]

Currently I have 2 jets of 0.049 inch. But without finding more details, the info I can find is that this is probably too low.

Sometimes you see them in the carb tune up specs in the factory manual but a quick search I cant find it either...

How do the plugs look?

these guys seem to have one NOS jet with PN AD listed for sale. Could buy it for less than $10 and cross check

1397-3827 Tilliotson Jet NOS

1397-3827 Tilliotson Jet NOS1 Available

stores.outboardparadise.com

 

[YOBE]

Sometimes you see them in the carb tune up specs in the factory manual but a quick search I cant find it either...

How do the plugs look?

these guys seem to have one NOS jet with PN AD listed for sale. Could buy it for less than $10 and cross check

1397-3827 Tilliotson Jet NOS

1397-3827 Tilliotson Jet NOS1 Available

stores.outboardparadise.com

Mine are similar to this JET. So that would fit I guess. Just weird there is no info on what size the originals are.

 

[alldodge]

Mine are similar to this JET. So that would fit I guess. Just weird there is no info on what size the originals are.

I'm sure there is in paper somewhere. Could ask a place like Mike's Carbs and he may have the info

 

[Scott06]

Mine are similar to this JET. So that would fit I guess. Just weird there is no info on what size the originals are.

As Ad points out I have seen it for some carbs in the carb section of manual or some addendums, but not for anything that old. I think I saw one for high altitude jetting but again not for a 165 engine.

if you can verify the size by getting a NOS jet may be best.

if the plugs look good may not be worth messing with.

 

[YOBE]

I did some deeper check on Mike's carb and I found this listing for Jets on Rochester 2GC carbs.
With some help of chatgpt and providing the full list of all models / engines, this one seems to be very close to my Mercruiser 165:
CHEVROLET TRUCK 6 SPL A/T → 7020140 (2GC, .044)

Seems to be a 6cyl engine of the in-line family. And this spec's a 0.044 Jet.
Mine are 0.049, so looks reasonable for a marine engine as they state that jets for marine engines are slightly bigger.

Makes sence you think?

 

[alldodge]

Agree