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82 Evinrude 70 cylinder one question

N

Nick0151

Regular Contributor
Hi guys,

I’m not sure if I’m starting to look for issues but it’s bugging me that at idle cylinder one when performing drop test is not as noticeable and other two.

Compression
127 -1
130 -2
130- 3

New fuel filter

Carbs are clean all jets clean seals new float is right. New hoses too.

New head gasket new thermostat
new pressure springs
New water jacket gasket
New intake gasket
Reed vales all checked and working as should be.
Spark is great jumps over inch gap
Timing seems fine.

Could it be exhaust housing?

Or any advice on where to look be appreciated!

Taking it out Sunday to give it blowout on the lake.

Thanks
 
That should have said new fuel pump***

I should also say it shakes a fair bit at idel but about 1500 2k will clean up
 
Have you tried switching the spark plugs around and see if the problem follows,if it does its a bad spark plug.If not try spraying a little carb cleaner down the carb throat and see if the rpms pick up.If it does you missed something when cleaning the carb.
 
Taken it out today and it’s rather bad to 3k then smooths out.

Also bogs down if I put throttle down hard but it’s ok if slowly accelerate.

Could it be float hight to high as i did change the one on number one.

Should the carbs floats all be set the same hight?

Thanks
 
Thanks again,

So when I adjust the float in each carb they should be parallel with the base of the carb.

I don’t think all floats are set like that.

The shaking started when I ran it out of fuel then flooded it twice do you think some crap has gotten into the thin pickup tube only thing I can think of.

When I cleaned it few weeks back I took the two air I think jets / orifices out and checked the numbers to make sure ok sprayed a lot of carb cleaner down there came out where I would expect. Think il have to shoot 120psi of air down there see if it moves any blockage.

I’m a bit lost as I think iv cleaned the carbs within inch of their lives. I have not removed those crush seals if that’s what they are called I can do if you think with help?

Thanks
 
I have taken carbs all apart and I don’t find anything bottom one was little dirty il attach photos below. All jets where clean. Taken fuel hoses off and make sure all ok.

Bottom carb had little bit of crap in.

I’m going to check my fuel tank and fuel hose il disconnect everything and blow it out with some air. Il also take the pickup out the fuel tank see if anything in there.

E83DB1E4-A57E-4E8A-B54A-B81C5488C43D.jpeg

97ACE7D1-2D50-470E-8766-3A2480C78F3E.jpegCA81149D-A84F-4FD4-93D6-4DE8B0D57D97.jpeg
 
Main jets clear as clear can be bowl is clean too it seems to have problems on idle and intermittent when above 3k it clears up that’s why Iv been looking at the passages to those but definitely clear now.

What I am think is water in the fuel I’m going to pump some out into a bottle tomorrow see if it was I’m hoping the is as otherwise I’m really out of ideas
 
stork55 said:
Have you done the sync and link on this engine,is the throttle plate closed on the #1 carb at idle.
Click to expand...
i have done the link and sync did it last sunday on the water it didnt make any difference.

faztbullet said:
Make sure you use new gaskets, do not reuse old ones
Click to expand...
i have ordered them for the carbs top carb float was set lower higher it was closer to the housing so guess higher if right way. I followed the service manual this time all 3 are set to the same and drop is within the spec of what they wanted set them all to about 38mm.



Carbs all clean and waiting the gasket blown through with carb cleaner and air.

taken the fuel hoses off from the boat and pressure tested them (blocked one side off and pushed air into it) in water no bubbles.

primer bulb did the same no bubbles coming off.

id say im happy with the fuel system well i cant think of anything else to check.. carbs be back on later in the week when gaskets arrive..

i messed round with the inlet manifold took the reed plates off and inspected them replaced the gasket at the same time.. i may take it off again and just make sure i cant see any light.

any ideas?
 
im not saying it is the issue but i have just been sat playing with the carb and noticed some play in the throttle plate actuator that connects to the linkage and moves the plate. i checked the other two and no play at all.. i have used some Loctite Ultra Gel to lock it in place.

it had a fair bit of play tbf could twist a good few degrees before plate started moving think that may be issue i guess would also stop it closing all the way with the slop.
 
I have ordered some Chris Carson Reeds as the top set was little bit of light not from then tips but from the sides of a few petals as off thought for the price id stick them on. wont be able to take it out for few weeks but will test in the barrel.
 
yes they are right size jets last week when i took them all apart checked all 3 jets in each carb to be jetted as per marine engine diagrams.

It ran really well before started this work on blown head gasket and inlet manifold but only did that as cylinder number one wasnt notable in the drop test.. iv cleaned everything and new fuel pump. i wish id taken a video of what it was like on the water with the bogging down and the stuttering on acceleration. above 3 ish k it flies still better than before and lot smoother its just getting up there but i cant test the carb clean again till the reeds come as its all apart.

il post link to my post last year when i brought the outboard you can see some fuel being blown out of #1 so may well always been troublesome.
 
The two little one that are behind the throttle plate when closed? Yes

And the larger one closer the inlet side

The two little passages by the low speed idle jet one on the left side.

All the passages tbf got soaked in carb cleaner / then some IPA and blew compressor air down it.

One thing I have not done is remove the crush seals but I could see light in all places.

Unless iv missed something

What do you think of the top carb if you watch that video can see fuel drops coming out few times
 
I think I may have worked out what’s up and if it is it’s 100% my fault 🤦🏻‍♂️

Looking at video of original drop test before head gasket, coils look to be in different place I think I have top and bottom wrong way round

0EFDC757-A4AD-44C9-9A65-7824A007C256.jpeg

The above is before I took it apart look at the numbering on the coil, that in the photo is top and middle P on the top on that one

Below is how I put it back together no p

8A36FF52-E1C1-4FFF-B60F-0BA33C4F5DA1.jpeg
 
New Reeds Installed, putting carbs back on and fuel lines today will test in barrel later see if any difference to #1 on the drop test cant take out on lake till 6th of Aug but should be able to test a bit on land
 
Good news done the drop test today and #1 is definitely more noticeable did really pick up to well in video but it so much better than before!


One question #1 carb lots of fuel coming out think float is set to high?
 
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