Question on running engine with muffs on and in drive

[WDC]

Good afternoon<br /><br />This may be a silly question but when I run my 85 hp 1973 Johnson with the muffs on(not in the lake) and place it in drive and increase the engine speed I do not hear the enging rev like you would if you had a car in drive on milk cartons. The propeller does spin faster and it does work in reverse. Is that because it's not in the lake.<br /><br />This problem was observed before I realized my waterpump was bad also. I am installing the new water pump this evening.<br /><br />Thanks for any feedback.

 

[Xcusme]

Re: Question on running engine with muffs on and in drive

Your motor will sound and run differently on muffs. On muffs , there's no backpressure,like you have when on the lake. Never over rev a motor on muffs. Don't make final carb adjustments,on muffs, again,it's a lack of backpressure issue.

 

[DJ]

Re: Question on running engine with muffs on and in drive

WDC,<br /><br />You CANNOT produce water pressure unless you can run the engine in a test tank (with test wheel) or the real thing-lake.<br /><br />I have found that the "Prop Muffler" can simulate back pressure, but not LOAD.<br /><br />While running on the muffs, keep your RPM's down (2000 Max) and use the flusher for it's intended purpose-flushing and basic engine checks.<br /><br />The '73' 85 HP has a special place in my heart, as mentioned previously. It is one of the most durable engines ever produced.<br /><br />Keep us posted.

 

[WDC]

Re: Question on running engine with muffs on and in drive

Thanks DJ and xcusme.<br /><br />Who ever had this enging, under the cover it looks spotless. The rudder is a little banged up but will be fixed at a later time.