CV740 rpm drop

[smalltimerpm]

Having issues with rpms dropping under a load. It runs great but it is sluggish getting up to high idle. It runs great and doesn't miss. Once I move forward or backwards the rpms will drop dramatically and pick back up. It gets worse with pto engaged.
I've pulled each plug wire off while running but both have same effect and it almost dies... if not does die out. I haven't put a compression gauge on it I just did the old blow the thumb off the hole trick. It seemed to have good compression. I've been thru the carb, even replaced it with one I know works great. Has good fuel flow. The spring travel seems to be the same on all valves but the lifters are hydraulic. Any help would be great. Also the motor does have about 940 hours on it and not sure if it's been gone through or not.

 

[Fish]

What is the spec. number?

 

[smalltimerpm]

Cv740-3141

 

[Hammermechanicman]

If it has a manual choke try adding some choke when it bogs down. If it does carb problem. Try NEW spark plugs. If you have 2 inline neon testers install them and see if there is any spark miss under a load. The neon testers won't show a bad plug, just a bad coil.

 

[smalltimerpm]

Ok I'll give it a try. Oh I also forgot mention it does seem sluggish. It acts like it is out of time but it isn't sputtering or missing

 

[bertsmobile1]

Check the exhaust pipes and see if one feels hotter than the other
A twin running on one cylinder will do what yours is doing .

 

[hlw49]

Intake manifold gasket blown?

 

[smalltimerpm]

Check the exhaust pipes and see if one feels hotter than the other
A twin running on one cylinder will do what yours is doing .

Oh Bert! Your a very smart person and some would learn a lot of information you have to offer! I'll touch it and see what happens.

 

[smalltimerpm]

Intake manifold gasket blown?

I'll check to see

 

[smalltimerpm]

I'm gonna try to pull the lifters and see what the cam looks like the best I can without tearing down the motor. I'm leaning more towards cam or timing but I'm not really sure.