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1982 70HP evinrude not right.

N

Nick0151

Regular Contributor
Changed lots of bits including new head gasket fuel pump and good few others reeds to chis Carson reeds.

Last time was out it seems to have lots a bit of power in the low rpm range it’s hard to get onto plane with a larger pitch prop that before hand would take little bit of time now it just won’t do it iv had to change to my towing prop 15p

Winter season is here and going to take few bits off and try to iron out last few bits..

Top cylinder isn’t responding to drop test as much as others..

Looking at some forums and some guys on YouTube points me to top crank seal.

Question think that could be it?

2nd question how hard is that seal to replace. I don’t have any flywheel puller tool and I take it that would need timing setup again?

Thanks
 
I doubt it is the top seal.----No need to worry about timing if you decide to replace that seal.----What " bits" have you changed so far.----What testing have you done.----Post the actual compression values.----Hopefully they are 130 PSI or greater.
 
Hi racer,

You gave lot of advice at start of the season, soooo new parts are…

Head gasket,
Head resurfaced
New water jacket gasket
New thermostat
2 new pressure relief springs
New carb bowl gasket
Carbs all cleaned and jets checked.
New fuel pump
New fuel lines
New inlet gasket
New Chris Carson reeds

Il check compression tomorrow or when it finally stops raining 🌧

After rebuild it was

1-127
2-130
3-130

Thanks
 
Could be cylinder dropping out? could be your fuel pump too. We had a 2004 yamaha 70hp and would have heaps of power then would drop to 3400rpm, was also hard to start and drank heaps of fuel. We replaced it and it started like a treat and drank much less fuel and most importantly could reach full Rpm again. You could also pull the air cover off the carbs and check how much fuel is being dumped into the carbs incase one carb isnt doing what its ment too.

Hope that helps.
 
That would make sense at it the top carb and if low pressure be hard to get up to the top bowl, it runs ok on the 15p cylinder drop test not as much difference when top one is pulled.. il look for an oem pump as the one I got was an Amazon special
 
Yeah I mean check all your furl lines and if the top bowl isn't filling with fuel could be a partially blocked needle or faulty float inside the carb. But yeah we bought a alixpress fuel pump for ours and worked a treat so far. If you have replaced it it's probably unlikely to be that however even if it isn't you might get some better fuel consumption.
 
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