Logo
FULL SITE MENU

74 mpi low rpm

D

duckisland3

New member
"Last year I put my 33' se

"Last year I put my 33' searay away running ok
I changed cap, rotor, wires, plugs, elbows, risers & recuped props. This year I can't get over 3400 rpms wot ( should be 4400 ) I removed the props and had them rechecked, regaped plugs, cleaned and reinstalled fuel injectors & changed water/fuel filters- no change."
 
"Was the pitch changed on the

"Was the pitch changed on the props? It doesn't seem that any of the other work you did would have this affect on the rpm. If the work was done right.
My guess is you checked for the correct timing and the spark plug wires are correct so what eles but the prop would cause the drop in rpm.
If you can, locate another set of props and see if it brings the rpm back."
 
I removed the props and hade t

I removed the props and hade the prop shop check them again they said that the pitch would have had to be changed by 5 degrees. Thanks for your thoughts.
 
Yes I understand that there wo

Yes I understand that there would need to be a large change in the pitch. My thought was you may have received someone elses props by mistake. The only other thing is the advance in the distributor is not moving or there is a restriction in the exhaust. Did the ECM's loose their maping? Temp sensor out?
 
"Now your over my head [img][/

"Now your over my head
I think I need to have the engines computers checked at this point. Thanks I'll let you know how I make out
PS with no load ( neutral )the engines will get up to 4800 rpms"
 
Most engines will run high rpm

Most engines will run high rpm without a load on them.
Are you sure it is both engines or just one and it's holding the other one back?
It would be strange for both engines / ECM's to have the same problem.
 
yeah both engines are doing th

yeah both engines are doing the same thing I ran them one at a time and the results were the same about 3200 rpms
 
"Whoa! You mean you gassed onl

"Whoa! You mean you gassed only one at a time, with the other at cruising rpm? That won't deliver full WOT rpms.

Jeff"
 
I just tried to see if there w

I just tried to see if there was a difference in behavior so I left 1 in neutral and the other wot and they both only went up to 3200 rps. This afternoon I took the props off again and tomorrow I am going to another prop guy.
 
"thanks everyone for trying to

"thanks everyone for trying to help!
Problem resolved!
Turns out I broke a sensor on the intake manifold. I had replaced it however, the engines went into " Guardian " mode. I just had to have the error codes on the engines reset, and that resolved my problem"
 
Back
Top