120 HP big block Looper,

[Madmac74]

Hi , great site ya have here ...
Just got a 1985 2.0 V-4 looper, and am having issues with idle and WOT. it seems to coff lean at idle ,and die , it only reaches 5200 rpm and it surges at WOT between 5000 and 5200. Its running on 50:1 Marine mix, fresh Fuel pump diaphram (VRO disable), Fresh plugs ,gapped at .030',I'm pulling my hair out here as this thing should scream and fly on my welded 18.5 foot Alluminum flat bottom!!

I checked total timing at full throttle and got 16 Degrees .. The cover says it should be 22.... I'm leaning toward Re- jetting as I'm about 1000 feet higher than the last place it was. Plus after reading around It seems like thats all a 140 HP is .. a re-jetted 120??

Any and all help would be greatly apprecieated

Thanks, Parker, In Prince George

[racer]

Carb bodies are different as are the reed block assemblies. You need to verify fuel pressue first on your surge, I would also prop to run 5800 rpm.

[rsukup]

85,86 and 87 are called small block Loopers. 120 had 5 reeds per cyl. 140 hp had 6. I believe the 85 may have had 4. All the carbs are different and jetted different. Check for bad reeds (gaskets) by checking for spit back at idle with the air box off. Some V4s had a crank seal go bad. (Loose play at the top of the crank) Cover each carb with a card slightly to see if it speeds up. More help might be on the Marine Engine forum.

[Madmac74]

Thanks for the reply's . I was considering installing an electric fuel pump and ditching the stock set-up... I guess a 122 Cubic inch 2.0 L engine is considered a small block then...thanks for the clarification. jetting goes as follows Mains are 57D Intermeadiate are 46 idle are 14.




Marine engine forum???? Guess i'll try it too
Thanks a bunch

MAC

[black junk racing]

Replace the top crank seal I've seen then cause all sorts of problems

[evilrude 1]

The 2L is the larger of the v4's---your's; if its a 1985 is a 1.8 small bore.

[Madmac74]

Ahh yes , and confirmed by the Manual .. 110 C.I.( 1.8L). Looks liks 1990 was when they went to 122 C.I. (2.0L).

MAC

[Madmac74]

So back out to the lake ....,The fuel issue i thought Ii had was actually an over propping issue making it seem as thought I had a fueal problem, wouldn't rev out , wet plugs .....So off came the 21 Pitch 4 blade . I was only able to get 18 degrees of total timing. I propped for 5800, with a 17 pitch turning point 3 blade and got 5700 RPM, so I'd say thats ok . Sure took alot of timing , like all the way out on the course adjustment and almost all the way out on the fine adjustment . Am i doing some thing wrong here? Engine runs good however, boat will cruze @ 35 MPH and do 40 MPH WOT. But the holeshot kicks ass!!!. this skiff is gonna be packing a bit of weight so i think i have a pretty good set up. Plugs were perfect Tan in color. Still setting up the new Control cables so they jive with the Throttle. Its hard shifting and finding neutral. Today was a GOOD day..

MAC

[racer]

Timing should be set with engine running under load at 5000 or above. If you need to back the stop all the way out you need to make sure the key way and timing pointer are correct, if these check ok you need to look at the center hub of the flywheel. Idle timing does not effect wide open timing

[Madmac74]

Thanks racer, Thats exactly how I set the Timing. So , remove the flywheel and inspect the key-way, and check the center hub of the flywheel.Will do!!

i did re-set the Control cables , the throttle was set too tight , thus hanging the idle at about 1400rpm. to the boat launch tomorrow..

MAC

[Madmac74]

Sorry for the late reply... Last time out I had good mid range and top end but my Idle was too rich. I think i should lean out the idle bleeds . currently its got 14's. Can i drill them out with the correct sized bit? Anyone know a source. 2-3 months til boating season \

MAC

[Madmac74]

still looking for input regarding the above....

thanks MAC