Johnson 6hp 6RL76A Motor Not Starting

[Joe Reeves]

Re: Johnson 6hp 6RL76A Motor Not Starting

Why do I see three rings on pistons that are for this model engine listed in E-Bay? My pistons have two rings each. And if I replace them with 30 over pistons, where do I get the hole set from. Rings and pistons and clips?

The 1976 6hp Evinrude/Johnson (Model 6RL76A) incorporates a two ring piston. The one you're looking at on eBay must be a earlier model.

 

[Mikekee]

Re: Johnson 6hp 6RL76A Motor Not Starting

This listing is on E-Bay, it shows a three ring piston, say's it fits my model too. Yes I have a two ring in mine.

376994 386692 Piston Ring Assembly Evinrude Johnson 5 6 HP Vintage NLA | eBay

 

[Mikekee]

Re: Johnson 6hp 6RL76A Motor Not Starting

Called my buddy about his fuel. He said it was about a week old he said that he likes it oily for his weed eaters.:facepalm: So I think I'm buyin some in the morning:laugh: and make it with a little less in oil mix.:facepalm: Just to get this bit.. workin.:flame:

 

[raczekp1]

Re: Johnson 6hp 6RL76A Motor Not Starting

bought 6 hp from 72't
instaled new cols, carb cleaned, 90 psi in both holes and i couldnt start.fuel is no sucking from carb
decided to change rings(on the way to me),on piston there is 3 rings.checked ring end gap(0.3 mm), recomended is (o.12-0.38)
will see what happens

 

[OptsyEagle]

Re: Johnson 6hp 6RL76A Motor Not Starting

Called my buddy about his fuel. He said it was about a week old he said that he likes it oily for his weed eaters.:facepalm: So I think I'm buyin some in the morning:laugh: and make it with a little less in oil mix.:facepalm: Just to get this bit.. workin.:flame:

Make sure you mix with TC-W3 outboard oil. Weed eater 2 stroke oil is not the same and should not be used, but of course, would not cause your motor to not start. Might cause it to not start after it has started and ran for a while, but you should get some running time out of it.

I don't think your problem is fuel. You seem to have eliminated that one in my mind. Spark is OK, although is it timed correctly? That is determined by the flywheel key and the point gaps. Assuming the key is fine and you set the points good, we are left with compression. 50psi is pretty low, but as many have said, it should get you some form of ignition. How did you do the compression test and was it 50psi on both cylinders?

Also, is it possible that the crankcase is not properly sealed?

 

[Mikekee]

Re: Johnson 6hp 6RL76A Motor Not Starting

Well i think this engine has too low of compression. The rings I ordered from E-Bay were for a bore size of 1-15/16". After I ran my hone with Carbide stones through both bores, the rings have an end gap around 35 thou. I know that's too much, so back too E-bay we go. This time from the same seller I bought 2.0 rings. I'll have to wait and see the end gap on these. My compression was 50, but now they are lower and not the same any more. One is down to 40. If these new rings are a bust, Anyone want a parts motor??

 

[Mikekee]

Re: Johnson 6hp 6RL76A Motor Not Starting

The new fuel mix this morning was from my Go Kart, 135cc lay down enduro. Yes it goes 150mph and has over 10,000 race miles on her. This made no difference except a few fires and that was all.

 

[Mikekee]

Re: Johnson 6hp 6RL76A Motor Not Starting

What is the proper torque settings for the head? I found out that one long bolt was so bad that it felt like it was going to brake. And the two short ones next to the plugs were stripped out. I had the torque gun in inches set too 175. Now I have to fix this mess.

 

[nwcove]

Re: Johnson 6hp 6RL76A Motor Not Starting

not sure on the specs for your motor, but 175 inch lbs sounds like its about triple what is needed. also the sequence is very important.

 

[Mikekee]

Re: Johnson 6hp 6RL76A Motor Not Starting

What 16 pounds is too high??

 

[Joe Reeves]

Re: Johnson 6hp 6RL76A Motor Not Starting

The 6hp model head bolt torque is 60 to 80 inch pounds....... 5 to 6.6 foot pounds.

 

[Mikekee]

Re: Johnson 6hp 6RL76A Motor Not Starting

The 6hp model head bolt torque is 60 to 80 inch pounds....... 5 to 8 foot pounds.

80 inch pounds is 6.6 foot pounds. What's the book call for? Should I be around 8 foot pounds?

 

[Joe Reeves]

Re: Johnson 6hp 6RL76A Motor Not Starting

Disregard the 8 foot pound mention.

Sorry, that was a typo.... should have been 60 to 80 inch pounds....... 5 to 6.6 foot pounds.

Do not exceed those figures. Note that it sounds like you have at one time already tightened those bolts to 175" pounds. If so, the threads may not be in very good condition, so if you're up near 80 inch pounds and it feels mushy... stop.

 

[the machinist]

Re: Johnson 6hp 6RL76A Motor Not Starting

Those that have added their info here have pretty well covered most situations.

The one thing I do not see is anything pertaining to position of the twist grip throttle. These can get sloppy & the markings may not be true indication of whether it is Fast, Start or Slow. These motors will not usually start if the throttle is slower than you think it is. Try to turn it wide open to see if this will change the timing & at the same time give more fuel into the motor for starting. You can then adjust it after starting. Also on that motor if I remember right it may not have a throttle cam roller off the carb, but just the carb lever being a plastic arm. These arms can get worn at the contact point with the timing plate cam. If this is the case, then your carb is not putting enough fuel at the right time into the manifold.

 

[Mikekee]

Re: Johnson 6hp 6RL76A Motor Not Starting

OK, I got my new rings and installed them. Got the block back together and sealed everything. I put it to the test and compression is 50 on both cylinders, I know this will get better after seating the rings in. So I tried to start her, well this POS is still not running. Plugs look like they are dry, so I took the carb off again. Checked the float and it is a little bit lower that the gasket surface of the carb when inverted. Will this cause the fuel problem I have been experiencing all along with this? All the passages in the carb are clean. I swear I'm going to burn this motor, I'll post the remains if anything is still there.

 

[raczekp1]

Re: Johnson 6hp 6RL76A Motor Not Starting

when you install new rings, did you check ring end gap
should be (0,125-0,35) mm
if its more then 0,35 mm means cylin der is worn to much
last week I instaled rings, fit ring end gap to 0.20 mm
i got compresion 90 psi
i know shoul be better but motor start every time first pul

 

[Mikekee]

Re: Johnson 6hp 6RL76A Motor Not Starting

I took the engine to a engine shop, and we measured the gaps and we set them perfect. This now needs to run and they will seat better. I just need to know if the carb float is set to proper height. And if it was too low for this to be my problem not starting in the first place.

 

[raczekp1]

Re: Johnson 6hp 6RL76A Motor Not Starting

i had some smal outboard, less then 60 psi motor runs only with choke on

 

[Mikekee]

Re: Johnson 6hp 6RL76A Motor Not Starting

OK people, I just saw the set point's mark on the side of the fly wheel. T set point and B set point marks. And a set of two small marks on the timing plate. Someone said to set points with the key way pointing to the wiper on the points. This will not work using the marks on the fly wheel. So I ask you all, were do I set the timing plate too for these marks to work? If I set the throttle to full OFF, then the points are open to about 5 thou. By the time the key way get's too the wiper they are open to .020. But not open too .020 using these marks.

 

[nwcove]

Re: Johnson 6hp 6RL76A Motor Not Starting

shouldnt matter where the throttle is set, as long as the points open when the timing mark(s) on the flywheel are centered between the two marks on the mag plate. have you read the top secret file at the beginning of this forum? good info there.
is there any lateral play in the magplate? if so it will mess up timing quite bad