200CCP with 2003 Ficht Ram 175

[ktisdall]

I'm trying to get the engine running in its correct max rpm range.  My understanding is that is 5250-5750 according to the Kirschbaum list.  Most opinion is that the ficht RAM engines like living at the higher end of their rpm range so I'm hoping to get it to 5600rpm.

With an aluminum 14x19 I got 4800 rpm and 35kts (there was current with me in a river so kts is approximate)

So I tried an aluminum 15x17, expecting to get 5200 but only got 5000rpm.   I didn't check kts/mph.

Is it possible I need 15x16 or 15x15 on this boat?   Anyone else with a 200CCP with info on this?

--Kevin

[flounderpounder225]

I'm trying to get the engine running in its correct max rpm range.  My understanding is that is 5250-5750 according to the Kirschbaum list.  Most opinion is that the ficht RAM engines like living at the higher end of their rpm range so I'm hoping to get it to 5600rpm.

With an aluminum 14x19 I got 4800 rpm and 35kts (there was current with me in a river so kts is approximate)

So I tried an aluminum 15x17, expecting to get 5200 but only got 5000rpm.   I didn't check kts/mph.

Is it possible I need 15x16 or 15x15 on this boat?   Anyone else with a 200CCP with info on this?

--Kevin

The 15 x 15 Enertia is what was the perfect match for my boat and motor combo, but my 245 Osprey is a lot more boat than the 200 CCP, and I am running a 250 HPDI.  I wouldn't think you should have to drop all the way down to 15 pitch to get your Revs where they need to be?  Does the engine appear and sound normal, have you checked to make sure you are getting full throttle from your controls.

[ktisdall]

The engine is new to me this year.  But the rpm's vs speed seem to be in the ball park with the VRO 175 I had for the last two years.   I was mainly surprised that the WOT went up only 200rpms for a pitch reduction of 2".   I thought it should be about 200rpm's per inch.   Although the diameter of one is larger than the other by an inch.   Not sure how that affects RPM.

The throttle control seems to work normally, but no, I have not confirmed it is opening the throttle on the engine all the way.   I will check that.  

I thought I would check the tach against an optical test tach to see if the gauge might be a bit off on the low side.   It does also show idle around 800 rpms which seems low.

I'll confirm both of those over the weekend.

Good thoughts - thanks.

--Kevin

[ktisdall]

Ok problem (probably) solved.

I changed to a 15.5x17 stainless apollo/michigan prop that I had but it needed a new hub.  Got the hub and tried it and I get 5100 rpm WOT indicated.  I did look at the linkage and it does get pushed to its full range.    I also read the flywheel rpm with a laser tach and at 1300rpm indicated, the flywheel read 1700 rpm.  So the tach appears to be 400rpms low.  I need to try that at a higher rpm to make sure it's consistent.  Then adjust the boat tach.

This probably means with the 15.5x17, full fuel, one person, flat water I'm getting ~5500-5600rpm at 41.5mph boat speed (gps).  That's right where I want to be.

--Kevin

1984 200ccp / 2003 Evinrude Ficht Ram 175