1985 evinrude 30 hp prop power issue

Cutty15

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I have an 1985 evinrude 30 tiller E30telcoa. Rebuilt carb, new fuel lines etc. replaced water pump and lower seals. Runs great but once it’s in water and under load the prop doesn’t seem to spin with engine speed. Out of water the prop does not free spin while in gear. Is there a shift linkage adjustment that you know of on these?
 

Chris1956

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Prop hubs can give out. These connect the blades to the brass hub.

If the motor revs up and the boat doesn't, those are often the issue. Prop shops can fix 'em.
 

Cutty15

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Prop hubs can give out. These connect the blades to the brass hub.

If the motor revs up and the boat doesn't, those are often the issue. Prop shops can fix 'em.
If the prop hub was bad would I be able to spin by hand while in gear?
 

Chris1956

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Possibly, if the hub was real bad. You can make match marks on the brass hub and the blade, run it in gear in the water and see if they move in relation to one another.
 

jimmbo

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Either the hub is bad, or the prop is ingesting a lot of Air/Exhaust. Does the gearcase housing have any damage in front of the prop?
 

Cutty15

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No damage. Just seems like a slip where prop isn’t pushing water. Figured it was prop hub or shift linkage but I don’t see that the shift linkage is adjustable.
 

jimmbo

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Is there a clacking sound when the engine is running in gear? The shifting mechanism is either in gear or out of gear, it is not like a Friction Clutch in a car/truck.
 

Cutty15

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No clicking. Just thought there was a dog that could be not fully engaged but that would make sense it would be making a noise if that were the case. I’ll take the prop in and see what they say.
 

Cutty15

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Tried the new prop today and same issue. Boat powers to about 5 mph the Rpms continue but isn’t pushing boat any faster. It is a long shaft on a tall transom. Also checked compression today for fun and it’s 110 on both which should be fine. What else can slip on these between the motor and prop?
 

racerone

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Step #1 ----Make sure that the LOWER shift rod is fully screwed into the lower unit.
 

jimmbo

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He is saying make sure that #49 is screwed all the way into #12
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Cutty15

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Sorry new to the lower unit work. Can I just grab the lower rod and twist or is there a trick?
 

Newyota

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Sorry new to the lower unit work. Can I just grab the lower rod and twist or is there a trick?
It’s hard to turn it just by fingers typically when the brass connectors are together.Use your half inch wrench to try and turn it in.It easily could have been backed out when you were taking connector apart by turning lower brass nut instead of top one to pull lower unit.I have had that happen alittle but turned them back in.The Phillips screw wasn’t removed down on the bottom of lower unit was it?
 
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Cutty15

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It’s hard to turn it just by fingers typically when the brass connectors are together.Use your half inch wrench to try and turn it in.It easily could have been backed out when you were taking connector apart by turning lower brass nut instead of top one to pull lower unit.I have had that happen alittle but turned them back in.The Phillips screw wasn’t removed down on the bottom of lower unit was it?
@Newyota - That’s exactly what happened. When I dropped the lower to replace the water pump I must have backed out the lower rod thread. No slip now! Thank you for the diagnosis.
Final issue is that in gear the throttle doesn’t want go wide open. Only 70%. Will go wide open in neutral. Have replaced all fuel lines and plugs and taken carb apart and cleaned and reassembled. Has new gas. Tuned the throttle arm and carb advance. Still just not getting last bit of throttle. Any suggestions beside a carb rebuild kit?
 

Cutty15

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@Newyota - That’s exactly what happened. When I dropped the lower to replace the water pump I must have backed out the lower rod thread. No slip now! Thank you for the diagnosis.
Final issue is that in gear the throttle doesn’t want go wide open. Only 70%. Will go wide open in neutral. Have replaced all fuel lines and plugs and taken carb apart and cleaned and reassembled. Has new gas. Tuned the throttle arm and carb advance. Still just not getting last bit of throttle. Any suggestions beside a carb rebuild kit?
Also has a new fuel pump.
 

jimmbo

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If you had performed the Link and Sync correctly, the spark will be fully advanced and the Carb fully opened, however they don't move together much. Almost all the Spark Advance will happen before the Carb opens even a bit, then after Full Advance occurs will the Carb open fully. A good Service Manual will explain the Procedure. I did say a Good Manual, meaning a Factory Manual.
 

Cutty15

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I didn’t perform a link and sync. I don’t know what that is and I don’t seem to be able to find it online. Are you suggesting that a timing advance will fix the specific issue I outlined? That I can get to full r’s in neutral but not in gear? Sorry I’m new to wrenching and these older motors are harder to find good info. That’s why I’m here
 

jimmbo

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Revving in Neutral means F all.
Do you have a Service Manual, hopefully a Factory one?
 
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