1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

[Haffiman]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

Waiting for the pics of the sparks, they might tell a lot.
As for the timing, just grind off some from the stopper to allow the optical sensor bracket to move a bit further back at idle. Did that myself on a couple of engines with too high idle. Not sure which gaskets you have between throttle bodies and reed, but there were some problems in that area and change of gaskets.

 

[Big flop]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

It looks like you can back the timing roller
off and the arm will come back to the stop
It looks like the roller is holding it 1/4 in open?

Mike

 

[SparkieBoat]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

you do not know how many times I have kicked myself for selling that 115..man that motor ran good. timing arm is hitting the stop, a little grinding will cure the problem. hopefully test run tomorrow or friday, been a busy week.

 

[SparkieBoat]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

I order a new tube of gel seal II. I am going to re-seal the crank case before the next test run, besides that mothers day cost me my gas money...lool

 

[aerobat]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

and the sweet thing is... mother does not care how many horses it pushes on the prop, she will just love you for a great boating day ! i wish you and the family much fun on the water !

 

[SparkieBoat]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

thanks bro. God Bless all, and happy mothers day.

 

[boobie]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

Sparkie, is that roller hitting the arm where your arrow is pointed ?? If it its, it shouldn't be when the throttle is backed all the off. Maybe some twisted linkage ?

 

[SparkieBoat]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

it has about 1/8 inch clearance. linkage does not look twisted or deformed in any way. I have a friends motor to compare with..his runs out pretty good, still will not keep up with a merc 150 xr motor though.

 

[clanton]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

You have the pistons in the correct cylinder. There is a port and starboard piston.

 

[SparkieBoat]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.



I did not know that Clanton, I did put each piston back in the hole it came out of, but I did not know there was a difference. so it may be possible the previous owner swapped some pistons around when he rebuilt it???? how do I tell the difference, I have a few pics of the pistons out of the motor. would it even run with the wrong pistons in it??

 

[metriccrescentwrench]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

I did not know that Clanton, I did put each piston back in the hole it came out of, but I did not know there was a difference....how do I tell the difference, I have a few pics of the pistons out of the motor. would it even run with the wrong pistons in it??

There are marks stamped on the face of the piston. My engine (as you know it's also a Frank Matthews special) had pistons from a mix of manufacturers and the markings variy by manufacturer. Also, in addition to pistons being specifically for the port and starboard bank they need to be oriented properly. I looked through the photos I took when I had the heads off thinking I'd post a couple here but the makings didn't really show up well in any of them.

so it may be possible the previous owner swapped some pistons around when he rebuilt it????

Gee, that'd be a shocker, wouldn't it? :facepalm:

 

[SparkieBoat]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

seems that the hole with the wrong piston would not create the draw through the carbs as strong as the others, I assume the port would not line up with the cut in the piston skirt. as I looked at my pic, I could see that the cut was the same on the top row (odd cylinders) and the same on the 2 bottom ones I can see. I do not think this is my problem, but I will keep it in the back of my mind.
would a engine even run if one, some or all of the pistons were in the wrong holes?

 

[boobie]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

Good point Clanton. Are the ports at different levels like the were in the old 90 * loopers. I can't remember.

 

[boobie]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

Sparkie, I just looked at a parts break down of this mtr and they do list different pistons for port and starboard.

 

[SparkieBoat]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

yes I can see the cut in the piston skirt is different, you can see it in my pic above...top row is 1,3,5 bottom row is 2,4,6, you cannot hardly see number 1 and nothing of number 2. all of the numbers on the pistons were turned in, I put them back like that

 

[Haffiman]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

Clean the piston tops and look for marking 'stb' and 'port' or an arrow. The arrow should point towards exhaust .

 

[SparkieBoat]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

there was no arrow, but there was some markings. I turned all the markings in toward the exhaust ports. I did not pay attention to if they said STB ot PORT though. I would have to pop the heads off again.

 

[captgord]

Re: 1994 60 degree 150 HP, only getting about 100-110 HP. cannot find the problem.

have you tried to pick up trim yet.