MERCURY SST120 or XR-2 block ?????

[FMP]

A light piston doesn't hurt

[Merc 2.5]

This is the compression test

Attachment 426211 Attachment 426212Attachment 426213
Attachment 426214Attachment 426215Attachment 426216

I don’t understand why the road bolt is very important for high rpm!
please explicate!
i have the oem 5/16 rod bolt smaller than 3/8 rod bolt of 2.5 efi offshore
with my road bolt how many rpm can arrive????
Attachment 426217this is my rod bolt!

The stock rod bolts r made to stretch when torqued. So if u reuse a stretched bolt it dosent have the tensile? strength left and will fail and send rod thru motor. When rebuilding pay close close attention to rod caps and torquing NEW rod bolts as per manual. I can get u A pic of a stretched bolt and a good bolt

[Flabenk69]

Hiii guys this is the results of rebuild motor new paint new decals


WHO CAN SAY ME THE RIGHT FUEL PUMP for race carb 2.0 outboard ????????

red Holley 2 amp 97 gph 7 psi ( 367 lph at free flow) not require fuel pressure regulator

blue holley 3 amp 110 gph 14psi ( 416 lph at free flow) require fuel pressure regulator

black Holley 4 amp 140 gph 14 psi ( 530 lph at free flow) require fuel pressure regulator

This is the Oem replace

[largecar91]

I have ran a blue and regulated it down. For racing, The best pump to use is a Weldon and have it set to run the lower pressures. You do not want to lean it out.

[johnmiffco]

an alternative to the cheap holley and high $ Weldon
is the Mallory 110 marine,,,,flows plenty for a carb merc,,,and has an adjustable regulator made into it'
gear rotor pump like the Weldon,,,not a slinger pump like the holley
ran them on lots of drag and sst120/140 motors with great results and life

[Capt.Insane-o]

The mallory pump work great but need a prefilter before them.

[Flabenk69]

This is the best forum of the world! Very very good guys!

I want to make a list of right fuel pumps for mercury race 2.0L

-Holley blue 3 amp 110 gph 265$ (pump , regulator, shipping ,duty)


-Mallory marine 110 gph 400$ only pump 175$ regulator

-WELDON marine saeJ1171 825$ Only pump 218$ regulator


Very hight price different!

what is the difference of a 2.0 with Mallory set ?Holley set ?Weldon set?

[johnmiffco]

all 3 pumps will flow more fuel than 2.0 merc can use
so if set at 6 lbs should not over power seats
so all 3 will work
Mallory and Weldon are gear rotor pumps so are more precise
holley is a vein slinger,,,,when 1 or more of the 4 veins sticks,,,,less volume,,,,,not a good thing
Mallory has a allen adjuster on bottom of pump can see in pic,,,so no need for the regulator as can lower pressure built in the pump,,,
also the non marine is over 100 cheaper and same pump just not extra coatings on windings and the black paint,,,
if going on a race only motor not a pleasure rider,,,,,,standard pump works well and has good long life,,,
ive raced sst120 for 10 yrs and ran Weldon and Mallory,,,,Mallory was less then 1/2 price and no issues ever

[Flabenk69]

Thank you John!
i bought the 110 gph Mallory 7 psi fuel pump item number 29256 ( 335$ pump, shipping, duty)

I don’t have bought the fuel pressure regulator, with this pump I don’t need it at 100%???

[Markus]

The Carter is the best pump for a carburated engine.

[johnmiffco]

yes do not need regulator,,,,'
as stated can adjust allen to 6 lbs and wont overflow the seats and still produces more fuel than need on 2.5

I don’t have bought the fuel pressure regulator, with this pump I don’t need it at 100%???[/QUOTE]

[Flabenk69]

Hi guys the Mallory 110 (416LPH) is arrived and mounted yesterday in the boat

with factory pressure regulator (7psi ) with this high pressure and flow , the mercury 2.0 liter
not exceed 4500rpm and run very very overflowinng!

I adjusted the pressure by unscrewing the adjustment screw almost to the maximum , the engine was up to 5000 rpm but it still seems very full of gasoline, don't run well !

i think , it’s possible that running with overfloating will ruin the spark plug?????

[FMP]

The Carter is the best pump for a carburated engine.

Part#? 6psi
https://www.jegs.com/i/Carter/180/P4389/10002/-1

[Capt.Insane-o]

You may want to put new needles and seats in the carbs.

[johnmiffco]

agree on above or ur floats are set too high,,,,,,