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

[Flabenk69]

hello guys I have bought this powerhead 2000cc with serial number 0D110741, who can say me the provenience and tecnical date of this engine?

rod code 636-8118 piston code 765-7441
425139425140425141425142
please help me!!!

[johnmiffco]

1992 xr2 by quick search of serial #
has timing arm so turns clockwise,,,,
sst120 had locked timing and turned counter

[Flabenk69]

This is an merc racing XR-2 of 1992 with 200hp on propshaft at 7000 rpm????

when arrived in my house I maked the compression test -—

1 117 psi
2 140 psi
3 140 psi
4 145 psi
5 140 psi
6 145 psi

the first piston was suspected and I put the inspection camera and I see the super breaked piston with 117 psi ��
425164

I want chance only the piston ! Is a good idea?

wiseco 3008ss fit in this motor?

[Markus]

Wasn't it 200hp on the crank?

[largecar91]

Wasn't it 200hp on the crank? Yes they claimed in the specs 180 propshaft HP

[Dave S]

Not sure what piston type..... Might be Shhhity cast.... def not ART cause smmmoth. top.... Ring turned so for racy speeds need top pins,,,,Still looks like nice motor....Dose it have steel or nick bores?

[Flabenk69]

I bought the original mercury piston STD size 3.125 ( real size 3.115 )
426072
I measured the size of sleeve 79,375 mm (3.125 in)
426073
Clarence of piston ring is 0,48 / 0,50

426074
how many rpm can arrive this motor ???

[largecar91]

8500-9000 no problem

[Dave S]

That is an art piston... and good Head gaskets.....vicktor.....

[Merc 2.5]

Measure ring gap bout 1 in below deck , ring gap should b round 24 or 25?

[Dave S]

RPMsssss depends on rod bolts.....

[Flabenk69]

This is the compression test

426211 426212426213
426214426215426216

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????
426217this is my rod bolt!

[nitro_rat]

I don’t understand why the road bolt is very important for high rpm!
please explicate!

The rod bolts keep the big end of the connecting rods inside the crankcase...

[Flabenk69]

I don't understand when rod bolt is good for high rpm or not !

only weight difference ?

[Dave S]

The thing that breakes most motors is..... piston stop.... IE... lean out. RPM wise the rod bolt is the next week point. Use SPS bolts if you can get them. Red Loctite em'.... after cleaning good.

[FMP]

A light piston doesn't hurt

[Merc 2.5]

This is the compression test

426211 426212426213
426214426215426216

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????
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 motor440043 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
440060
blue holley 3 amp 110 gph 14psi ( 416 lph at free flow) require fuel pressure regulator
440061
black Holley 4 amp 140 gph 14 psi ( 530 lph at free flow) require fuel pressure regulator
440062
This is the Oem replace
440063

[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)
440133

-Mallory marine 110 gph 400$ only pump 175$ regulator
440135440139
-WELDON marine saeJ1171 825$ Only pump 218$ regulator
440136440138

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)
440193
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 441996

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,,,,,,