2000 challenger problem

[kasne]

Hello im new here,

i have a challenger that i just bought, i noticed this past weekend that when i full throttle both engines the one on the right only hit about 4500rpm until i dropped the throttle for that engine to an idle then back to full throttle and then it hit 7000rpm

i checked the accelerator pump and it did squirt fuel

any ideas where to start next?

 

[Dr Honda]

In 2000... there was a 2000, 1800 and a std Challenger. What one do you have? (I'm assuming the std since the others had a Merc engine)

 

[kasne]

sorry its a standard Challenger

 

[Dr Honda]

OK... it has a pair of 720 engines.

I'd probably start with checking the compression, and cleaning the carbs.

 

[kasne]

ok i checked the compression of both cylinders on both engines and all are 85 +- 3 psi. i did notice when i took it out for a ride when i closed the choke a 1/4 of the way the engine hit 7000rpm. so i figured its the best time to take the carbs apart and clean them.
upon de-assembling them i noticed the carb on the working engine had 2 clear diaphragm pumps and the the carb for the othe engines where black( dont know if that matters). other then that they both where clean and the jets where clear of debris. the only other thing i can do is to swap carbs side to side and to insure that it is the carb

 

[El Toro 33809]

Compression of 85 is very low. I would be surprised if it would start in the water with compression that low.

 

[kasne]

Compression of 85 is very low. I would be surprised if it would start in the water with compression that low.

the one engine runs great so i dont think thats my issue, the other engine runs great if i hold the choke partly open (which to me means that it leans out at mid-hi throttle)

 

[jhjesse]

Need to check your compression guage.
With 85 psi compression I doubt the engines would even crank in the water. S/b 150psi.