35 johnson pitch

huntingdeer

Petty Officer 2nd Class
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Jun 21, 2012
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i have a 35 johnson(1988)model with a 10.13 pitch on a 15 foot trident fish and ski.It runs about 30 mph.The boat barley plains.Is my prop too big?I do not know much about props but i know something is not right.Thanks for all the help.
 

steelespike

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Apr 26, 2002
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Re: 35 johnson pitch

Check out "read this first" at the top of the prop forum.Get us as much info as possible.
If it is really 10.13 pitch thats really low read that excellent hole shot!
I think that may be your diameter.?
 

Texasmark

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Dec 20, 2005
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Re: 35 johnson pitch

30 mph for a 35 hp on a 15' fish and ski doesn't sound bad to me. Sounds just about right. Back in the 50's when 35 was a big boy, 30 is where they would run and do a mediocre job of pulling 1 skier behind a light boat, lightly loaded, on 2 skis. 35 ponies is just not all that much whoopie my man.

Mark
 

huntingdeer

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Jun 21, 2012
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Re: 35 johnson pitch

All i see on the prop is 10x13.the weight the day i took it out was about 500 pounds.thats about all i know.
 

Texasmark

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Dec 20, 2005
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Re: 35 johnson pitch

All i see on the prop is 10x13.the weight the day i took it out was about 500 pounds.thats about all i know.

10 is the diameter of the blades and 13 is the pitch. Sounds like some of the numbers used back when.

HTH,
Mark
 

huntingdeer

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Jun 21, 2012
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Re: 35 johnson pitch

Does the pitch sound right for that motor?the motor does not sound like it is wot.
 

steelespike

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Re: 35 johnson pitch

Using a couple of guesses(not a good idea) calculator indicates about 5800 rpm to go 30 mph.
You may have too much weight in the stern and/or may need to trim down for hole shot.
Can you give us the details of the weight in the boat? Does it plane with just a light load?
Is the boat glass or aluminum?
 

huntingdeer

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Jun 21, 2012
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Re: 35 johnson pitch

Its fiberglass.the motor is trimmrd all the way up.well the pin is in the first notch.i do not know weight.and slso what is hole shot?i had the people that was with me stan in the frount but it went slower.
 

jimmbo

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May 24, 2004
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13,642
Re: 35 johnson pitch

Its fiberglass.the motor is trimmrd all the way up.well the pin is in the first notch.QUOTE]

First notch? do you mean first notch from the transom? Your last post indicates you are trimmed out, not in when accellerating. Holeshot is basically describing the time it takes to get the boat on plane from idle. Placing ballast in the bow will cause the boat to plow, resulting in lower speed.
 

steelespike

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Apr 26, 2002
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Re: 35 johnson pitch

Please explain "barely planes".Do you mean barley on plane or it takes a long time to plane.Be specific,about how long to plane.
Is your speed by a GPS?
trimming:: trimming "up" the prop is moved away from the boat usually slower to plane but faster once planed. Trim "down" prop is closer to the boat should plane quicker but the boat may lay down too flat. If manual trim a compromise is needed for reasonable plane time and good speed.
 

huntingdeer

Petty Officer 2nd Class
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Jun 21, 2012
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Re: 35 johnson pitch

The boat is trimmed all the way up.The speed is clocked by gps.And by barley planing i meant by not sitting flat in the water while on plain.
 

Texasmark

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Dec 20, 2005
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Re: 35 johnson pitch

In reading the exchanges and your getting worse comment with passenger movement, you are plowing: Boat has too much hull in the water, nose diving. You need to move your tilt pin out until you get the best improvement. Moving it out will raise the bow (front) of the boat and result in less engine loading (more rpms) and pushing it too far out will cause problems getting up on plane, or could ventilate (engine revs up but boat speed falls off).

On what the engine sounds like and Steel's guess, you are at two extremes here. One the engine is lugging (your comment) and otherwise it is overrevving and it would be screaming. But Steel said he assumed some things sooooo.

Not familiar with an '88 but the old 35's of the 50's era only ran up to 5000 max rating and they were very quiet and the sound was low pitched....that was one of their selling features.

Tell you what. Go out by yourself and tweak the tilt pin for best performance. Then add your passengers and have them move about for best performance. Tell us how it went.

Mark
 

steelespike

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Apr 26, 2002
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Re: 35 johnson pitch

I don't understand how a boat can do 30 mph and be barely planed. Perhaps trim down one notch.
If its planing right you wouldn't want it too flat flat on the water.
Excellent suggestion.A light test run.
 
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