no power past certaiin point - 70hp chrysler

[jdubya]

Here's a short summary of the events leading up to my problem............<br /><br />16' crestliner (mid 70's) with 70 hp chrysler was tied to the dock when a storm came through, broke away from the dock and sank on the right side submersing the engine. Did not completely tear down motor cause we got it running very soon after taken out of water. Cleaned carbs, iginition system, new fuel tank, greased and lubed everything, changed LU oil.<br /><br /><br />Got it running good, launched it yesterday, fired right up. got past the no wake area, started to get in the throttle easy ( just to make sure everything was ok) and the boat started moving pretty good. When I got to a certian point in the throttle, the motor reved up but would not pull. Let back on the throttle, and it started moving slowly again. Got back in the throttle and it did the same thing. Seems like it is slipping out of gear, but no grinding noises and no shavings in the LU oil. Drained the LU oil when I got home and completely tore down the LU. Main shaft was ok (splines) and forward and reverse gears were fine. Shift mechanism was fine. Only thing I cant see is where the main shaft goes into the motor (looks good looking up at it)<br /><br />I can turn the motor over using the prop with it in gear and it doesn't slip.<br /><br />I am new to boating and I am stumped. Any help would be greatly appreciated.<br /><br />thanks.

 

[johnrolf]

Re: no power past certaiin point - 70hp chrysler

Check your shift cable. Mine just did the same thing. The plastic around the shift cable had a crack in it and the cable was buckling out of the side. The previous owner had electrical taped it up tightly and the tape was loosening up, so I retaped it up tight and its as good as new! Also check your controls, something may be slipping in there causing it to fall out of gear.

 

[jdubya]

Re: no power past certaiin point - 70hp chrysler

thanks

 

[johnrolf]

Re: no power past certaiin point - 70hp chrysler

let me know how it goes, I'll help in any way I can.

 

[eurolarva]

Re: no power past certaiin point - 70hp chrysler

Sounds like a spun hub on the prop. Seems wierd this would happen when the storm happened unless the prop hit something hard. It is easy to test. Draw a line on the prop to the cone where the cotter pin holds the propeller on. Use permanant marker or finger nail polish. When it slips check to see if line is still lined up. When the prop hub goes it needs the high torque from the motor for it to slip. You probably could not spin this by hand.

 

[jdubya]

Re: no power past certaiin point - 70hp chrysler

that sounds probable.<br /><br />It just looks to me that the prop is one piece. I don't see any kind of hub in it. I'll try that next trip out to the lake.

 

[eurolarva]

Re: no power past certaiin point - 70hp chrysler

Inside the prop hub is rubber. When you hit something with the prop it breaks the contact with the rubber to metal. It acts like a shear pin. It seems pretty common. If the prop is bad you will have to get a new one or get yours fixed. A local marina should be able to point you in the right direction to getting yours fixed

 

[jdubya]

Re: no power past certaiin point - 70hp chrysler

yeah, i just went and looked at it. I see what you mean now. Can I just take the prop in and have it tested or should I try your fingernail polish trick first.<br /><br />Main problem is that the only guy in town that works on boat motors doesn't do chrysler's. Plus it costs me a 7.00$ a day (50$ a year) pass to take it on the lake to test it. Took a total of 5 minutes last time to find this problem last time.<br /><br />thanks for your help<br /><br />oh, any place I can buy a new or used one online?

 

[johnrolf]

Re: no power past certaiin point - 70hp chrysler

Try www.tacomapropeller.com . They had the best price around on the prop for my 35hp. Try ebay too, every once in a while they have chrysler props for sale.

 

[eurolarva]

Re: no power past certaiin point - 70hp chrysler

A prop shop should be able to tell you if it is spun. Chances are the prop cant be fixed if it is old. Seems I read a thread here about the older chysler props cant be rehubbed. First of all this spun prop is just a guess. I think it is a pretty good guess. I would test the prop before buying a 150 dollar prop and finding out you had a hole in your fuel pump and the prop was fine.

 

[jdubya]

Re: no power past certaiin point - 70hp chrysler

but the motor runs fine. If i had a hole in the fuel pump wouldn't it not rev up when it loses power. My problem is just a total loss of propulsion past a certain point. It doesn't bog down just stops pushing the boat.

 

[eurolarva]

Re: no power past certaiin point - 70hp chrysler

I used fuel pump as an example. Sorry. What I meant to say is I would hate for you to spend 150 on a new prop and find out something simple is wrong with your motor. I used fuel pump because it only cost 10 bucks to overhaul. I am still betting on a spun prop.<br /><br />Good luck

 

[jdubya]

Re: no power past certaiin point - 70hp chrysler

OH ok. I'll take it in and see if my local guy can check it out. We don't have a "marina" per say, just a local boat mechanic/salesman in town. <br /><br />I found a another whole chrysler 70 horse motor sitting in someones front yard that has been for sale for at least 3 years. I know it's prolly shot, but would be good for parts (prop) if it can be had for under 100$