1996 Evinrude 150 GL model missing HP

[SparkieBoat]

Ok guys you have probably read all of my post on this motor over the last few months. Basically I purchased the motor for a 17.5 McKee craft boat that I have purchased. The motor has never pushed this boat as fast as I expected. I have cleaned and checked carbs, done a link and sync, and rechecked multiple times, replaced intake manifold gaskets, check compression ( 110-118) replaced plugs twice (QL78YC) and double checked gap. replaced stator, power pack and timing sensor, and plug wires all with new CDI brand. I have checked timing, all new fuel lines, new VRO style fuel pump, used test fuel tank, and checked to make sure the reeds are working by visual inspection and making sure carbs were not "throwing fuel" at WOT. I have tried it with 19 and 17 SS pitch props with very little change, around 37 MPH at 5K RPM, 17 pitch prop slightly slower with about about 100 more RPM. also tried a 23 SS pitch prop..4K rpms at 35 MPH.
I have a 1989 100 HP Johnson that I put on the boat with a 15 pitch SS prop it hit 5400 rpms at 35 MPH, so I figure my 150 is producing about the same HP when compared to this, maybe slightly more. Motor cranks and idles like new, does not miss or skip. slightly "bogs" when you hit WOT, runs best at %95 throttle. If anyone can help me find my missing HP I would be VERY VERY appreciative.
Thanks Sparkie

 

[ezeke]

Re: 1996 Evinrude 150 GL model missing HP

What high speed jets do you have in your carburetors?

 

[SparkieBoat]

Re: 1996 Evinrude 150 GL model missing HP

I do not know..I will look tomorrow. To my knowledge they are the original ones. but you never know what someone may have done to the carbs before I got the motor. Thanks Ezek, never even occurred to me to check that.
Sparkie

 

[nymack66]

Re: 1996 Evinrude 150 GL model missing HP

Whilst you at the engine checking the jets note the serial numbers stamped at on the side of the carbs and post it please. This may help you also
http://www.boats.net/parts/search/B...ETOR & INTAKE MANIFOLD - 150 H.P./parts.html#

 

[emdsapmgr]

Re: 1996 Evinrude 150 GL model missing HP

You do have an under achiever! The GL model is comparable to the older GT/XP engines-where they run about 10% more hp than on marked on the side of the cowling. Yours has the high compression heads (338311) from the 175, 175 carbs with nearly the 175 size jets (#69D) and should put out 165 prop hp. The last time you had the lower unit off, did you check the midsection exhaust tube and the lower unit for exhaust obstructions? You would be suprised to see what parts (obstructions) wind up in the lower unit exhaust system, when a powerhead blows and is replaced.

 

[SparkieBoat]

Re: 1996 Evinrude 150 GL model missing HP

I did not pay close attention to exhaust for clogs, but I did look at it while changing out impeller. I will check carbs and jets first then pull foot and check exhaust...great thoughts...let you know what I find.

 

[SparkieBoat]

Re: 1996 Evinrude 150 GL model missing HP

ok heres the numbers....436798 carbs with 70D jets and a 341267 throttle body. I cannot find any of these part numbers on the net. looks like I may have a mix/match carb system. can Anyone identify these numbers??

 

[ezeke]

Re: 1996 Evinrude 150 GL model missing HP

Could that be 438798? I do find 436798 as a carburetor body, but not as an assembly.

 

[SparkieBoat]

Re: 1996 Evinrude 150 GL model missing HP

it is defiantly 436798 stamped into the side of each carb body..so it may be the number for just the body..only other carb # is 334961 stamped on bottom of float bowl. there is another # on the throttle body it is 340934 I cannot find anything on any of these numbers. thanks for any help..I guess I need to determine if these are the correct carbs, it seems that they are the incorrect jets. BTW the only way I know the model of this motor is from a number on a plug on the back of the motor it is G3771212..I just looked up my post where Faz told me the info it is a 95 not a 96 year model..here is a copy of his post...
The serial number supplied is for a: 1995 J150GLEO produced on 8/11/94, shipped 8/18/94 and purchased on 9/10/94
I do not know if this makes any difference as the numbers seem to be the same for both years..

 

[SparkieBoat]

Re: 1996 Evinrude 150 GL model missing HP

just noticed he had a J in there...some one must have put a Johnson power head onto an evinrude body...

 

[SparkieBoat]

Re: 1996 Evinrude 150 GL model missing HP

starting to think Emd may really be onto something now with the exhaust blockage, I would not have thought the power head was ever removed...looks like it was.

 

[SparkieBoat]

Re: 1996 Evinrude 150 GL model missing HP

ok foot dropped and nothing in the exhaust passage. looked up with a flashlight, I did notice that the top of the right side passage was pretty clean, I could see the color of the metal, the left side was covered in black soot from top to bottom.

 

[SparkieBoat]

Re: 1996 Evinrude 150 GL model missing HP

are the part #s somewhere that I am not looking...not sure if I have the right carbs or not

 

[emdsapmgr]

Re: 1996 Evinrude 150 GL model missing HP

Even in 1995, the 150GL (High performance version) came from the factory with .069 high speed jets. The 175 model carbs always used the .070 high speed jets. Someone may have put 175 goodies (heads carbs) on your 150 block. That should not really be an issue here, though it could be a slight factor in your bogging problem. It is interesting to see that the exhaust passages are different color. Unusual. Perhaps one side is washed from water ingestion in a cylinder? Is there a difference in the appearance of the spark plugs between the two sides? Also, is is possible the fuel/oil pump is leaking oil back into the suction cylinder, causing an overoiling issue on that side?

 

[SparkieBoat]

Re: 1996 Evinrude 150 GL model missing HP

I had the head off of the right side..cylinders all looked normal to me. I was told if there was a water leak one cylinder would be clean looking. when you say fuel/oil leaking into suction side, do you mean leaking through the pulse line? It is a brand new VRO style fuel pump without the VRO and I premix. Also new intake manifold gaskets and throttle body seals. The different color of the top of the exhaust passage is curious though. it may be an indicator of my problem. and spark plugs all look the same. this is a real confusing problem.

 

[ezeke]

Re: 1996 Evinrude 150 GL model missing HP

That carbon build-up could be an indication that the thermostat is not working on that bank.

 

[SparkieBoat]

Re: 1996 Evinrude 150 GL model missing HP

never had any over heat problems, but I did replace the t-stats anyway. I do not think it is an heat problem.

 

[ezeke]

Re: 1996 Evinrude 150 GL model missing HP

never had any over heat problems, but I did replace the t-stats anyway. I do not think it is an heat problem.

Running cold would be the problem; those thermostats rarely stick closed - usually opened or the seats are bad.

 

[SparkieBoat]

Re: 1996 Evinrude 150 GL model missing HP

I will check motor temp...but to touch it it seems to be warming up to normal operating temp to me.

 

[SparkieBoat]

Re: 1996 Evinrude 150 GL model missing HP

pulling power head today to take a look at exhaust ports..anything in particular I should be looking for??? I will post some pics.