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1978 evinrude 35 timing help???

A

Aminoacid

New member
Noob here
I need to check timing on this engine. Replaced lots of parts and it runs as if timing is off.
Can anybody give me The specs and procedure to time this thing?

Thanks in advance. Walleye run is on now and need to get my line wet!
 
Flywheel key could be sheared.----Other than that the timing normally does not need adjustment.---Unless of course it has been tampered with.-----What is the motor doing / not doing.---What trouble shooting steps have been done ?
 
Have you adjusted engine sync? There is no timing adjustment just adjust spark advance with throttle opening and adjust the slow needle in gear in the water.
 
I acquired the engine as is on a trade.
after carb rebuild and another ultrasonic cleaning nonchange in run condition. It’ll run, backfire and rev but a struggling rev... backfire sometimes.
i replaces both plugs, coils, fuel pump, new fuel, fuel lines. Compression is a 122 psi and 121 psi. Water is circulating when it runs. I’m not sure what engine sync is? Is that the carb cable wide open to a top dead center /0 degrees mark?

Ive never really dug deeper than that in marine engines before. I have some experience with 2 stroke engine.
 
Flywheel key is good.
Adjusting the engine sync helped quite a bit.
How can I check if the timing is good?
does anyone know where I can find the procedure tonchecknthe timing? I ordered a repair manual for it but that won’t be here until next week.
 
Unless you have a test prop on it the motor is going to struggle to reach top RPM. The tank is a restriction and if you are running with the hood off it is very possibly sucking up it's own exhaust.
 
I can get it in the water and run it at full throttle to check timing. I just need to know the specs.
also, is there a way to check timing on land by just cranking the engine with spark plugs out and grounded?
 
It did not have electric Start but I added that in myself.
I found the post stating set the crank timing 4 degrees less than the spec setting to avoid pre ignition and piston damage. I don’t know what that spec number is , will it be stamped on the engine or do I have to wait until the repair manual arrives. ?
 
If you did not mess with the factory WOT stop it should be good. Once you get the manual adjust sync and link then adjust the slow needle if it has one.
 
Engine sync is also called throttle pickup with the engine off shoft into forward gear spin the prop if necessary. From slo advancethe throttle unit the roller is center between the two marks on the throttle cam. At that point the carb should be fully closed and just begin to open as the roller passes center. For link loosen the collar on the link rod under the flywheel. Take it to WOT then with one finger push the throttle butterfly fully open the with the other hand push the collar up tight to the pivot pin and tighten the collar. That should hold the carb fully open. Then check it a few times to confirm the carb just begins to open as the two marks pass center of the roller and the butterfly is full open at WOT.
 
Still trying to figure out the running issue.
i synced the throttle to the 2 marks on the cam filler/follower just as the carb butterfly begins to open.
now which screw is to adjust timing?
i took pics but not sure how to upload here
 
I gave up and took it to a marina. They said they adjusted the links and adjusted the carb and it’s running “well” but running hot so he suggested waterpump and thermostat. He is charging 2 hrs for the adjustment which I feel is total rape, I can’t see it take more than 30 minutes to adjust the link and turn a screw by an experienced mechanic.
do any of you guys know how far the butterfly should open at full throttle? It appears to open about 1/3 or so when I pull throttle all the way when engine is off, should it open fully as in laying flat? I feel like I’m being billed for a half ass job. Boat is still in their possession.
 
The throttle will only open a 1/3 of the way in neutral. The motor has to be in gear for the throttle to open all the way. At that point it should be open 90 deg. I don't know about the hrs since I don't know what they did. But if it runs right it probably took them less time than you could have done it in. Then no you are not being ripped off.
 
Look under the flywheel where the linkage goes there is a brass piece with a screw in it. Loosen the screw and shoft into forward gear you need to spin the prop as shifting. Take it to WOT then with one finger hold the carb filly open then push the brass collar fully forward touching the pivot pin and them tighten the screw. That holds the butterfly full open at WOT.
 
Ok got it.
They engine synchronized the the carb to engine.
I had already done a compression test, plugs, fuel lines, fuel pump, rebuilt the carb, then sonic cleaned the carb.
So you guys think syncing the carb/throttle and adjusting the needle on carb is a 2 hour job?

i didn’t know that it must be in gear to get the butterfly to wot. I kept telling the marina guy the butterfly doesn’t open fully on throttle...
yeaterday the bill was at 1.5 hrs then I asked if the throttle opens fully he said he will have the “guys” look at it, today it’s at 2 hrs and marina Still can’t answer my question about the butterfly wot and denies telling me it was at 1.5 hrs yesterday. I’m not crying about the expense, but principal. Marina even told he they adjusted the link it was out of wack and adjusted the carb, my carb only has 1 big needle which I think is the idle, it’s not a high speed and low speed type, I know how to tune a 2 stroke small engines, and have rebuilt a few.

Thanks for your help fellas. I will be pulling the boat out Monday.
 
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