1987 Looper v4 140 RPM only 4000

N

nymack66

God
Guys , Any idea why I can only get 4000 RPM at WOT ? Compression is 130/120 across all ports,
What size Jets do I need to install on my Carbs ? Currently 58D installed.
New everything on the engine,coils,plugs,wires,harness you name it minus pistion and rings !! . See photo at www.nymack66.com , I am restoring this baby..If I can get an album here it will be great I will move my pictures up
 
58D is for a 120HP, not a 140HP. Should have 61Ds in it. How many screws do you have holding the throttle blade onto the shaft? Somebody may have put 120 carbs on it, or a 140 cowling. And 4000 is no where near enough, i turn mine right up to 6100(rev limiter for 85, 86+ is 6700). These loopers need to turn at least 5600 WOT. Are you sure your tach is right?
 
It is a 140 for sure base on the power Pack etc
The gauge is Teleflex Vector 7000 RPM Tachometer
For 4, 6, or 8 cylinder gas engines
or 4, 6, 8, 10 or 12 pole outboard engine
 
Set it to 12 pole. And the 120 and 140 are almost identical, the only differences are the exhaust tuner, carbs and reeds. Power packs and everything else is the same, even the timing. The only differences cannot be seen without some disassembly.
 
Tach/RPM Issues

Just verify the setting on the Tach it is a Telflex Brand and it is set to 6 which per the instructions is for and outboard 2 stroke v4 engine, As for the High Speed Jets they are 64D. Is this an issue with low RPM 4000 max at wot ? I have spare jets I can swap back to 61d please let me know
 
Most all of the JOHNNY-rudes 2,3,4,6,8 cylinder outboards run on a 12 pole setting, as well as MERCURY V-6's and many others. Is setting 6 for 12 poles? Also what are the numbers stamped on the carbs? I went and checked the catalog and an 87 could have 59D's or 61D's, and if it was a late engine it could have 63D's in it. I know 86 was 61D's which is what my carbs had stock, but 87 was the last small bore and 88 was large bore(displacement, not carbs). It gets confusing with these things sometimes.
 
Thanks for all your help , Hopefully this helps

Yes the Tach is set to setting or dial 6 which equals to a 12 pole.
I was told my engine is a 1987 E140tlcua, The carbs I remove have 397907 & 397908 is stamped on em, The high speed jets the dude remove is 61d he told and bill me for complete replacements on all carbs , The carbs on the engine has no stamp on em , As for the high speed jets on the engine currently I am not 100 percent sure but I remember him saying 64d or something like that . I will remove and check em tomorrow afternoon . My Idle is all 28 , Intermediate is 16 starboard 20 on the port side as per the manual. What's on yours across the board ?
 
I remove a SS 14x3/8 x 19 only going 3000 to 35000 rpm, I install a 14.8 x 17 aluminum it is a 15 spline prop 3 blade
Remember I am restoring this boat I have no base line to work with , Please see www.nymack66.com for some photo etc , I am stump in regards as to why the engine is not giving me the RPMs everyone is talking about !!
 
I would try a 15 pitch stainless wheel myself, but somethin don't sound right here. Are you sure your hitting on all cylinders under load? Is the timing set to 18 BTDC @ 5000 RPM's(very important that it is set at 5K as the power pack has about 4 degrees of advance in it with RPM due to trigger and stator outputs). Loopers are CRITICAL of timing. I would get you a bo0ok and go through the carbs top to bottom, make sure the plastic bodies are not warped. Then set the timing and go from there. To bad you aint closer, I'd help you figure it out as I'm fairly proficient with the V4 90 degree loopers.
 
Timing and link and sync was done by local dealer Boat Tune. I can only assumed it was done correctly
Carbs re-built inside out
Carburetor 397907 & 397908
Idle Air Bleed #28
High Speed #61D (I am not sure what he replace this jet with )
Intermediate #16
 
Those sound like the early 87 same as 86 carbs. These are the ones I am running. I'm jetted with 63D's main, 14's intermediate, and 34's(or 36's not 100% certain on which) for idle. This works excellent in mine running 50%1 pre-mix with PENNZOIL synthetic blend oil. But I have some very mild porting done in the exhaust ports behind the sleeves, and my air box has been slightly ported as well and I have a .020 over bore. I still trhink there is a problem with your link and sync or in the timing department. These engines are CRITICAL of timing. 2 degrees to much and meltdown happens, 2 degrees not enough and your 140 is a 115. THEY HAVE TO BE DEAD ON! I learned this one the hard way:cen:.
 
Update

Here is what installed
Idle=28
High=64D
Intermediate=Starboard side=16
Intermediate=Port Side=20
Note per the Parts Manual this odd sizes for the Intermediate is normal for this engine
I will test it on the lake hopefully on Sunday
 
Update2

I forget to mentioned I change the High Speed jets back to 61D per repair manual , I will test and post the results
 
nymack66 said:
I was told my engine is a 1987 E140tlcua,
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nymack66 said:
I remove a SS 14x3/8 x 19 only going 3000 to 35000 rpm, I install a 14.8 x 17 aluminum it is a 15 spline prop 3 blade.
Click to expand...

Wrong lower unit you have a V6 lower unit none of the short shaft 20 inch motors had 15 spline lower units, they had 13 spline. Only the 25 inch 120/140 motors had 15 spline lower units. It could still be a 120 power head. My 120 and my 2 twin 140's both have 62D jets.
 
They did offer the bigger lower unit on 85 and some 86 140's, seen em with my own eyes. And I have 2 140 lower units that are both 13 spline V4 units. Your model number comes out to a 20" shaft, but you said before IIRC you said you have a 25" leg. Your carb numbers come out to an 86-early 87 140 carbs, but it could still have a 120 tuner and reeds which would give you a 130 I believe. I think you need to verify your tach, and then check your timing.
 
right ferm 13 spline but he said he has 15 spline that's either a 25 inch lower unit or a V6 which he has neither of. no 15 spline were on V4 motors with 20" shafts.
 
Skools Out said:
right ferm 13 spline but he said he has 15 spline that's either a 25 inch lower unit or a V6 which he has neither of. no 15 spline were on V4 motors with 20" shafts.
Click to expand...

I've seen 2 of the 20" legs with the 15 spline shaft on the 140's. They both had the 2.25:1 ratio in them as well that came in the hybrid V6 leg. The reason I wonder about what he really has in his engine is he said he has a 25" leg and his engine number has the L not an X for a 20" leg. Sounds like some parts swapping has gone on with this here engine.
 
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